Open Source Civic EV Kit

Open Source Civic-EV documents moved

2011-01-03T13:35:00.001-08:00

Hi All,

It's been a verrrrry long time since I posted here since I sold the Civic-EV.

Due to Google removing the Files and Pages feature of Google Groups. All files and documentation at the civic-ev Google group has now been moved to the "civicevkit" Google Site:

https://sites.google.com/site/civicevkit/

If you need to access the build instructions or Google Sketch-Up files, please go there now.

Happy New Year for 2011!

Cheers,
Tim

Saying Goodbye to Electric Blue

2010-06-16T22:04:00.000-07:00

Well, as most of you have seen, there hasn't been a lot of activity for several months on this blog. I sold Electric Blue to my friend Murray (shown above) and he is taking good care of her.

It's time to move on from this electric vehicle conversion hobby and see where life takes me. I have a reservation for a silver Nissan Leaf coming in December, so maybe I'll post my experience with it. Maybe I'll even reverse engineer some of the guts and share it with y'all.

Unless something major comes up, this will probably be my last post.

Many thanks to all of you who have supported me over the years on this project and best wishes to those who are converting, buying or just plain enjoying electric vehicles.

May you be well and happy on your path.

Cheers,
Tim

Analyzing PakTrakr Files with PrestoPlot

2010-02-06T15:10:00.000-08:00

I took the Civic out for a spin today with my neatly installed PakTrakr and captured some data while pulling some reasonably high currents.

I programmed the Synkromotive controller to limit the battery amps to 250 to help prolong the life of the batteries. It takes a bit of the acceleration edge off while on the freeway at 60mph, but otherwise, the power is just fine for commuting.

After loading the PakTrakr data into Excel 2000 (yeah, I know it's old...), I experience much frustration with trying to zoom into areas to analyze the data further, especially peak areas.

I turned to a freeware plotting program that we use at work for quickly analyzing performance data called PrestoPlot. After loading the comma-delimited-data from the PakTrakr log file into Excel, I removed all but the battery voltage columns and added an incrementing list of numbers as a first column. I can now export this as a tab-delimited textfile from Excel and import it into PrestoPlot for easy viewing.

Here's an exported image (click to enlarge) from PrestoPlot showing the whole dataset gathered from the PakTrakr. The data seems very spikey and I was concerned that some of my batteries were dipping lower than other.

Upon quickly zooming in with PrestoPlot, I was able to see that the big droops on one battery were accompanied by positive spikes on the adjacent battery. Note the green dashed lines in relation to the red dashed lines in the picture above (click to enlarge). Hmm..., sounds like the PakTrakr isn't filtering out noise quite as well as I'd hoped.

In areas where the system is rather quiet, the batteries seem quite well balanced. Perhaps my pack isn't as dead as I thought it was, but it has just lost a bit of capacity. Perhaps putting some 0.1uF capacitors on the adjacent signal lines going into the PakTrakr might help with this.

Not too sure what to do at this point, but at least I get a good clean sampling stream on the serial port under heavy acceleration.

Cheers,
Tim

Mounting the PakTrakr

2010-02-04T08:21:00.000-08:00

It's time to mount the PakTrakr on the dashboard.

Since I have a low-end model Civic, there are several unused accessory plates that I can tap into. Here's one that I popped out just to the left of the steering wheel. I drilled holes in the pop-out plate to match the mounting threads on the PakTrakr as well as a 1" hole to thread the wires through.

After taking off two nuts on the back of the PakTrakr, I decided to disassemble the whole thing just to see what was inside.

Here's the PakTrakr threaded through the pop-out plate with the nuts holding it on.

Finally, the PakTrakr is installed where I can see it reasonably while driving. Most of my information will come from the Link-10 E-meter, but if I want to see any bad batteries, the PakTrakr should display those.

I've routed the signal cable to the PakTrakr. I also routed the serial output cable with a serial extender and a serial to USB adapter around to the passenger side so I can plug my laptop into the Synkromotive controller and PakTrakr at the same time with USB ports. The car is looking much better than it did awhile ago.

One thing I haven't done with the Lifeline traction batteries is to run a conditioning charge on them. Yesterday I ordered a 0-30V 6 amp power supply so I can run a higher voltage charge on each individual battery. Perhaps that will help them regain some of their life.

PakTrakr Signal Integrity

2010-01-31T21:22:00.000-08:00

I finally got to trying out some filtering on the PakTrakr lines today with some pleasing results. I've read several places, that the PakTrakr signal line really needs a 0.1uF capacitor across it to deaden out any extra noise. My series 100 ohm resistor that helped on my previous EV didn't work this time.

I found a tiny 0.1uF tantalum capacitor at work. After bending one lead back on itself and cutting off the excess wires to leave 3/16" sticking out, I simply jammed the two leads into the rear end of the blue plug that attaches to the PakTrakr module. I'm hoping that the pressure between the plastic case and the metal pins will be enough to hold the contact.

After jamming the cap in there, I just wrapped a bit of electrical tape around the whole thing. I think a piece of heatshrink tubing would have been better, but I didn't have any of the correct size.

Here's my first graph of valid PakTrakr data (click to enlarge). I'm really impressed with how well the 0.1uF capacitors cut out all the extra garbage. This plot contains several times where I punch the accelerator and pull 300 noisy amps from the batteries. I still think that the series 100 ohm resistor between the rear PakTrakr module and the front one helps, but the capacitors do the trick.

It seems the PakTrakr modules really don't like to read the voltages on the balancers when they are shunting current around the batteries. Here's what's happening in the graph:

For the first 50 seconds, the batteries are charging and the balancers are keeping things even. The top battery on each monitor is measuring way low (12.3V) but my multimeter says everything is fine.
From 50 to 120 seconds the charger is turned off
From 120 to 130 seconds I start up the controller and get ready to back out for a spin. Whoops! I left my gas guzzler in the driveway and can't get out!
From 130 to 330 seconds, I'm parking my gas guzzler. Note that the two batteries that were measuring low are much closer to the average.
From 330 to 885 seconds, I went for a quick spin on the freeway and drew 300 amps from the batteries at several points.
From 885 seconds to the end, the car was just sitting there as I ran to get my laptop to collect data. Note that all the batteries seem to be at around 12.9 volts now, according to the PakTrakr.

I'm much happier now that the PakTrakr is reading non-garbage data. I can go on much longer runs and see which batteries are giving out first.

Ugh, time to get ready for the week...

Cheers,
Tim

Fixing the Batmon Resistors

2010-01-24T14:23:00.001-08:00

Well it's about time I get the Civic working again now that the weather seems to be getting warmer. The biggest concern I have with my current system is the Batmon balancer resistors. The existing ones seem to be always on the verge of catching fire.

To replace the existing resistors while keeping the same mounting holes, I cut some 2.5"x3" rectangles of aluminum and bolted some beefier power resistors to them.

Here's the rectangle of aluminum with the larger power resistors. I'm hoping this system has much more thermal mass than the last one and can dissipate more power safely. I used a 1/8" drill and 6/32-1/2" self tapping metal screws to hold the resistors on. The two holes in the aluminum on the upper edge have the same size and spacing as the prior holes that held in the previous resistors.

After I was all done, I had four resistor "packs" to replace. There was clearance issue with the resistors just behind the front grille, so I made a different heat-sink block (shown on the bottom in the picture) to fit the two 6mm bolt holes on the driver's side just above the grille.

Here's the heatsink and power resistors installed just in front of the motor over one of the front-most batteries.

Here's the old power resistor setup. Note the discoloration on the bulkhead from the smoke and excessive heat.

Here's the replacement setup. with the larger resistors and aluminum heatsink.

Here is yet another replaced unit on the driver's side in the rear trunk.

In addition to bulking up the resistors, I also increased the resistance from 3 ohms to 5 ohms. This won't have as much balancing effect, but I'm banking that it will dissipate enough to do a reasonable job while lowering the heat generation. If each Batmon board kicks in at 14.6 volts, my heat dissipation (V^2/R) goes from a worst case of 71 watts to 42 watts. Since the Batmon boards are actually switching on and off quickly, I should never reach the worst case situation.

The next step is to get rid of the noise on the PakTrakr lines. My series 100 ohm resistor didn't work, so I'm going to have to try a few other tricks.

Seeing the Nissan Leaf in Person

2009-12-17T19:38:00.000-08:00

Things have been nuts this week, but I did get a chance to see the Nissan Leaf come to Portland today. It arrived at OMSI this morning and the OEVA got a private session with the Leaf this afternoon.

Here's Nissan's spokesperson who graciously answered all our geeky questions about the car. The Leaf boasts a 100 mile range on a 24KW battery pack. I have a 14KW battery pack and I only get about 20 miles when going on the freeway. The 100-mile range of the Leaf is based on a profile called LA-4 which is mostly stop-n-go city driving around 25 MPH. Nissan did say that commuting on the freeway at 60mph would probably yield a range of 75-80 miles instead.

Here's the requisite photo op with the Leaf showing the charging plugs at the front of the car. The one on the left takes a 440V 50A input while the plug on the right takes the standard J1772 plug that the EV industry has been trying to settle on for years.

I'm still weighing in on giving up on my homebrew Civic-EV and just buying one a Leaf. I still have a few more months to decide.

When Things Fall Apart

2009-12-14T14:11:00.000-08:00

Yesterday was not a good day. My landline and internet connection went dead on Saturday and the lamp globe for my ceiling fan broke apart above my bed, putting glass shards in the covers.

This gave me an excuse to get off my computer and drive over to Home Depot yesterday (Sunday) to try and find a new globe for the ceiling fan. I had recently installed the PakTrakr system, so I cleared out the serial logging attachment and started collecting data. On the way to Home Depot, I missed my exit and ended up going another two miles to the next exit. I knew I had gone farther than my battery pack should have handled, especially in the cold, so I stuck to city streets and slowly drove home.

Halfway home, the battery gave out. I crawled into a Taco Time and asked if I could plug in. The manager pointed me to an outlet outside the building but he didn't think it worked. It didn't. After that, I walked a block away and found an auto parts place that was kind enough to let me plug in. After the car sat for 20 minutes, I had enough juice to get to the auto parts place. I also collected the serial data log on my laptop from the PakTrakr for later analysis.

After plugging in, my friend Ruth picked me up and dropped me off at home. I had an appointment last night near the auto-parts place. My plan was this: have a friend drive me to pick up the Civic (after four hours of charging), drive to my appointment, plug in there for an additional three hours and hopefully have 40% charge left to get home.

We'll, I picked up the car from the auto-parts place, drove to my appointment and plugged in. Three hours later, I came out and realized that the charger hadn't given the batteries any extra charge. After poking around under the hood, I also found a critical resistor that enabled the DC-DC converter had broken off. Without the DC-DC converter to charge my 12V battery, my car would die quickly with the headlights on at night. It was rather moot because I still had little charge in my batteries. It looked like the charger had given up the ghost on me.

I got a ride home from another friend (it's good to have friends when you own a home hacked EV) and called a tow-truck this morning through BWC (the environmentally friendly alternative to AAA). I felt rather sunk all night because the car is basically useless without the charger and the batteries will degrade rather quickly if they sit in a discharged state.

I got the car home later this morning, fixed the resistor for the DC-DC converter and tried the charger again. To my surprise, the charger actually started up. My batteries seemed to be quite out of balance and the charger just wasn't putting much amps into the batteries, even with the shunts not active yet.

I still have to analyze the system more, but here's what I think is happening: The charger can only generate about 175 volts because it gets it's input voltage by rectifying the 120V AC line. When cold, AGM batteries need a much higher charging voltage. If I look at the datasheet for the LifeLine batteries, I actually need to charge each battery up to 14.90 volts at 40 degrees F to get to 80% charge. Let's see, 14.90V x 12 is 178.8V, which is higher than the charger can actually put out. The battery shunts were actually working properly and only shunting the batteries when they reached 14.9V. Since the charger couldn't reach that level for all batteries simultaneously, only a few shunts kicked in before the charge current dropped precipitously, leaving an unbalanced pack.

In short, It doesn't look like the Belktronix charger can actually charge these particular AGM batteries under cold temperatures properly.

My next task was to look at some of the PakTrakr data I gathered. The serial log was heavily garbled, so I couldn't just load it into a spreadsheet. I had similar noise issues with the 914EV here, but adding a 100 ohm series resistor didn't clean up the issues.

I did find that under massive current draws that at least one battery was getting yanked down to 7.2 volts (ouch!). Either that battery is undercharged or I perhaps hurt it over this past year and it's (probably) damaged. It's too bad that the best battery data comes under a high current draw when the serial data is the noisiest.

This being the wintertime, it'll probably be a few months before things heat up to where I can effectively drive the car again. In the meantime I'm going to check out Nissan's Leaf this week and think about ditching all this unreliable homebrew stuff to buy a commercially engineered EV...

Happy Holidays!
Tim

Replacing and Saving the Aux Battery

2009-12-06T15:26:00.000-08:00

Well, the car's back on the road again. Yay! I replaced the 12V auxiliary battery (a group 30 motorcycle battery) and got a 2 year warranty on it just in case.

I remember in the past, I fully drained my 12V accessory battery at least twice by accidentally leaving the headlights on. In fact, I almost did it again yesterday when driving the car over to a friend's place. The car is a bit older and doesn't have an alarm when you leave the headlights on when turning off the ignition.

To prevent leaving on the Civic headlights, I installed a piezoelectric buzzer from Radio Shack with an inline diode.

Here is the buzzer with two fast-on connectors and the inline diode with the positive (red) buzzer lead. The anode of the diode is crimped to the fast-on connector and the cathode is crimped to the positive lead with a red crimp jumper. I probably could have soldered this and added heatshrink tubing, but this was faster.

The reason for the diode is that I only want the buzzer to be on when the headlights are on and the ignition is off. In the event that the headlights are off and the ignition is on, I don't want any current flowing backwards through the buzzer, possibly damaging it.

Here is the buzzer installed to the testpoints on the fuse block. I had already figured out this fuse block in an earlier post, so I knew which ones to tap into. The tachometer is gone, so I can tap into the fuse block where the tach light input was connected.

The second testpoint from the right goes to 12V when you turn on the parking lights or headlights. That gets connected to the positive buzzer wire through the diode. The third testpoint from the right is the ignition signal which goes to 12V when the key is on. The buzzer only activates when the ignition key is off and the parking/headlights are on.

I hope this saves me a lot of headaches with the new auxiliary battery. With temperatures dropping quickly, I don't know if I can get to work, but at least I can cruise around town with a heavy sweater on. (still no heater in this machine... :)

Happy Holidays,
Tim

Comparing Conversion Costs with Paul

2009-12-05T08:10:00.001-08:00

Paul Pancella (see link at right) put together a great spreadsheet comparing his Civic conversion costs with mine. There are a few minor updates, but things are very close for the most part. The only things that have changed on the Open Source Civic are the MES vacuum pump for the brakes and the fact that I ditched the custom tachometer and pillar pod. Even with these differences, the prices only change about $100.

Thanks for assembling this list, Paul!

Tim

(click on the picture below to get a full size version)

Hints from Paul on Paktrakr Installation

2009-12-05T08:03:00.000-08:00

I'm just cleaning up my e-mail this morning and found a message from Paul Pancella about more installation issues regarding the PakTrakr system:

I can share my experience with the PakTrakr if you want. Ken Hall was very helpful, but the device itself was a little disappointing. The main thing is to be very careful with installation. The directions mention it, but it can't be emphasized enough, the remotes are easily destroyed if the ring terminals contact any battery terminals out of sequence. Depending on your physical setup, this can be hard to avoid during installation, since long wires are provided for each input. I'd recommend taping over all the ring terminals except the black one before getting near the car, then untaping individually as you install.

The temperature data from the remotes can be very useful, but the calibration on my units is at least 10 F degrees off. This was on my list of complaints when I twice sent the units back to Ken, but he was either unable or unwilling to do anything about it.

The individual module voltages are reported to 0.1 V precision, but again at least in my case, a few channels have offsets larger than this (up to 0.4 V). This magnitude is obviously significant in terms of balancing, so you will want to check every channel against a meter after installation. The offsets appear to be stable, so they can be accounted for if known.

I assume you will still have the Link-10? The PakTrakr has a "fuel gauge" function, but I'd guess the one on the Link-10 is a lot better. It will be interesting to compare them. I think mine is not very useful, maybe in part because it gets fooled by big voltage swings with regen. The whole system probably works better with lead acid than NiMH anyway.

I just wanted to pass this information along to all of you.

Cheers,
Tim

Installing the PakTrakr, Dead Aux Battery

2009-12-01T20:51:00.000-08:00

Hi All,

The Civic-EV blog has been slow due to my bad batteries and being swamped at work. I got the recalibrated PakTrakr back a few weeks ago and finally had some time to install it tonight.

I've heard of some other folks blowing up their PakTrakr modules, so I tried a few tricks that seemed to work quite well in preventing spurious voltage spikes from killing the modules.

First of all, I needed to install two modules with six batteries apiece, so I split the battery pack into two halves. This does two things: it makes sure there is no current flowing in the cables and it isolates the two halves so that the PakTrakr modules don't see large voltage spikes when removing cables from the battery terminals.

Second, I put all the PakTrakr terminal loops in a plastic bag and only pulled one out at a time. This prevented the loops in the plastic bag from touching anything like the chassis or a battery terminal that could have provided a significantly higher/lower voltage.

Third, I installed each PakTrakr terminal loop from the lowest voltage up to the highest voltage and tightened the battery terminal at each step. This insured that each block of six batteries didn't get split up and introduce wide voltage variation.

The last trick involved connecting the two halves of the pack back together. Since I had to re-install a high current cable onto the battery lug, I removed the PakTrakr terminal first, touched the high-current cable to the battery lug (not to the Paktrakr terminal!) and then attached the PakTrakr terminal with a screw to the fully connected setup. Again, the intent of this was to prevent large voltage differences from blowing up the PakTrakr.

On a sadder note, I must have had a large leak in the system or a bad accessory battery, because it measured 2.9 volts after sitting in the car for a few weeks. This battery has probably been bad for awhile because one of the cells was bulged out, perhaps from the DC-DC converter dumping 40 amps into it. After some wrestling, I wiggled it out and will get a new one by the end of the week.

With the PakTrakr installed, I now have a good tool for seeing which batteries are dying first. Since I ran the car on a rather empty and unbalanced pack, I suspect I killed a battery or two. All batteries are at a nice 13.0-13.1 volts at full charge, but I suspect that some have significant loss in their capacity. We'll see...

John's PakTrakr Display

2009-10-30T08:39:00.000-07:00

I shipped the PakTrakr modules back to the owner (Ken Hall) for calibration. Ken mentioned that they were rebuilding their calibration unit and would send the modules back as soon as it was finished.

I also received an e-mail from John Barton who used the open-source Civic battery rack design as a starting point for his own lithium-ion battery racks for his Civic DelSol:

Hi Tim,

I'm finishing up my second ev conversion, this time its a '93 Honda del Sol. My blog is http://mt-ev.blogspot.com. I'm also finishing a display for the paktrakr that runs on windows ce 5.0. I've got a basic version running on a GPS. Since you are using a paktrakr I thought you might like to give the display I wrote a try. Let me know if you are interested and I can send you an early version of the bits. I'll be blogging about it in a day or so.

The display I'm using is this:
http://www.dealextreme.com/details.dx/sku.22067

Also it requires a serial to bluetooth adapter like the IOGEAR.

Regards,
John Barton

It looks like he has a cool display that takes the PakTrakr output and shows in a user friendly format. I'm quite swamped these days, so I'll consider trying it out if things slow down this winter.

Looking forward to getting my PakTrakr back...

Installing the PakTrakr

2009-10-16T20:38:00.000-07:00

I took some time to install the PakTrakr modules today. I was a bit disappointed in the voltage measurements from the PakTrakr remotes, so I'll probably send them back for recalibration. Here are the voltages I measured:

Unit #1

Battery #	Battery(V)	PakTrakr(V)	Difference(mV)
1	13.43	13.5	70
2	13.49	13.7	210
3	13.48	13.4	-80
4	13.49	13.9	410
5	13.52	13.9	380
6	13.28	12.9	-380

Unit #2

Battery #	Battery(V)	PakTrakr(V)	Difference(mV)
1	13.41	13.5	90
2	13.46	13.7	240
3	13.47	13.4	-70
4	13.46	13.7	240
5	13.5	13.7	200
6	13.29	13.5	210

Unit #2 isn't too far off, but batteries 4, 5 and 6 on unit #1 have too much error to accurately determine the state of the pack. I contacted Ken Hall at PakTrakr today for advice before I send the units back.

To help with air resistance, I might run to the plastics store and cover the entire front grille with a sheet of ABS plastic to see if that cuts down on the drag as well as the cooling effect on the front batteries...

Range Anxiety

2009-10-03T08:42:00.000-07:00

As you've probably noticed, things have been a bit quiet here. The new vacuum pump is working well and is nicely quiet.

As the temperatures drop, the capacity of my batteries drop as well. After almost a year of hard driving, I suspect the batteries are also losing capacity. Over the past week, I've been driving a gas car because I had long errands after work that would have exceeded the maximum range of the Civic-EV. The few times I did go into work, I ended up crawling along at five miles an hour for the last half-mile.

If I force myself to stay under 55 miles an hour at all times and use hypermiling techniques as much as possible, I don't lose power near the end of my commute, but as temperatures drop, I fear that I won't even be able to even get to work.

This is the classic problem with electric vehicles: range anxiety. I have plenty of power from the Warp9 motor, but the battery current and capacity just isn't enough for my commute anymore. I can't confidently drive on the freeways anymore because I might lose power after ten miles of pushing it past 60 mph. If I stop commuting with the electric vehicle, that takes away 90% of my driving, which makes owning the car somewhat pointless.

The first thing I'm going to do is install a PakTrakr monitor. This is something I should have done a year ago to accurately monitor each battery. The Link-10 E-meter is good, but doesn't monitor individual batteries. For all I know, I might just have one bad battery in the pack. I already have the PakTrakr on my bench, but I haven't had time to install it. I just might do that this weekend.

Some options to consider:

Purchase a whole new set of batteries for $3000 (ick!).
Spend a lot of time making the car aerodynamic like the Aero-Civic
Redo the system with lithium-ion batteries and double the amp-hours for $10,000 and lots of time (ouch!).
Sell the vehicle at cost minus the price for the batteries, go with an ICE and buy a Nissan Leaf when it comes out.

After installing the PakTrakr, I'm going to try and commute for a few more days in this colder weather to see if things still work. Perhaps I only need to replace one battery...

New Vacuum Pump and Fixed Wiper System

2009-09-05T21:51:00.000-07:00

Sorry folks, no pictures today. I'm taking this long weekend to just relax and get some things done around the house while avoiding the crazy Labor Day weekend traffic.

One thing that's really been annoying me about the Civic is that the intermittent wiper setting doesn't work. After taking awhile to pry out the ICU (Integrated Control Unit) mounted on the back of the fuse box, I opened it up and tried some tests with a 12V battery to verify failure. After going to LKQ self-service auto-parts, I lucked out and found a Civic with another ICU in it as well as a grey trim piece I was missing. After shelling out a whopping $6.50 for these salvaged parts, I came home, snapped in the spare ICU and the wiper system started working again. Yay! I'm all ready for the long rainy winter here in Portland.

On a more relevant note to you EV folks, I also spent most of the day replacing my old Gast Vacuum pump and vacuum chamber with an MES 70/6E Swiss-made vacuum pump from MetricMind. I was lucky enough that it fit in the same space as the Gast pump and the vacuum tube from the pump to the brake assist chamber is only about 16" long. The MES pump is MUCH quieter than the Gast system, has a built in one-way valve and much less hysteresis than the Gast system. While it cost more ($315 instead of $285), the price difference wasn't that much.

I just finished my first test drive about 30 minutes ago and I really like this new vacuum pump. It's far quieter than the Gast system and has much more even braking pressure due to the smaller hysteresis. While the MES pump does come on much more often, it's so quiet I can only hear it when the car is completely stopped at a light without much noise going on around me. My initial thoughts are very positive and I recommend this for new people converting EVs.

Now that the intermittent wiper system is fixed and brake vacuum pump is upgraded, I don't plan on doing any more work on the Civic for awhile. I think the next major project (If I don't go out and purchase a Nissan "Leaf" outright) is to upgrade the batteries to lithium-ion types when the AGM lead-acid batteries die. Hopefully that will be two years out.

With the downturn in the economy and factory-made EVs being announced for next year, I've noticed far less EV projects happening these days. If people are doing conversions, they're doing them to older, more "classic" cars. These next few years are going to be quite interesting.
Drop me a comment if you're still working on a Civic EV. It's good to hear what projects are going on.

Cheers,
Tim

Controller Overheating and Vacuum Pump Issues

2009-08-22T18:53:00.000-07:00

It's been awhile since I've posted because, well, things are just kinda boring and working well on the Civic-EV. I passed 4,000 EV miles a few weeks ago and things are still moving along.

For those of you who have been keeping track of weather in the NorthWest lately, we had a hot spell at the end of July. One day of that week got up to 107F. I had a bit of a scare coming out of work when I found that the Civic-EV wouldn't start at all. The paint is dark blue (almost black) and the engine compartment was probably up around 115 degrees. After opening the hood and running the fan on the controller for 15 minutes, the car finally started to move forward without faulting.

I made it almost home. Coming off the freeway, I stopped at the stoplight on the exit ramp and the controller faulted and simply refused to go further, despite repeated "reboots" by toggling the ignition key. Fortunately, two wonderful people helped me push the car to a near by parking space across some local light rail tracks (we had to dodge the MAX light rail, yikes!). I let the car sit there until 10pm to cool off. When I came back at 10pm, it started up and I drove home.

Needless to say, I was a bit concerned about this hot weather situation. I contacted Ives, the controller designer at Synkromotive, and told him about the problem. His response: we've had that problem for weeks. All you have to do is turn up your CPU thermal limit from 50C to 85C degrees. Geez, I wish he woulda told me that before the heat wave hit. The car seems to be running just fine now, even on hot days.

Another issue I seem to run into (now that I'm driving a lot more) is that the hysteresis on the pressure switch for the Gast vacuum pump is rather large. This means the vacuum in the system to assist the brakes varies quite a bit. 90% of the time, this is no problem, but the 10% of the time when there is little vacuum in the system, the brakes hardly work at all. I have to pump them a bit to drain more vacuum and get the pump started again. When slowly coming to a stop, this isn't a big deal, but in emergency stop situations, this has been an issue.

To solve this problem, I purchased a $300 vacuum pump from Victor over at Metric Mind that is much quieter than the Gast pump and should have much tigher hysteresis on the levels of vacuum in the system. I haven't installed the pump yet, but I plan to soon.

Other interesting news: I'm resigning as chairperson of the local Oregon Electric Vehicle Association. It's been a good run for the past two years, but I'm tired of running the organization and it's time that someone with better organizational skills to step up.

Ross Peterson just finished his Civic-EV during the past two months based on the open-source Civic-EV kit and he's got the "EV Grin." I was delightfuly surprised to hear that he didn't have many issues building his battery racks based on the open-source plans. His batteries are a slightly different brand than mine, but they are still group 31 size and fit the plans well.

Stay tuned for details on the vacuum pump installation. Otherwise, best wishes on all your projects.

Getting a new Synkromotive Controller

2009-07-14T20:17:00.001-07:00

After mentioning the motor controller temperature faults to Ives (the designer) at Synkromotive, he suggested we swap it out for a newer one. I went into the shop this evening and swapped out the controller. Ives looked at the old one and basically told me that I had beta test unit #2 with tiny heatsinks, bad ventilation and very little filtering on the temperature fault circuitry. Apparently other customers have had the same issues and the new controller should be far better.

One other thing the folks at Synkromotive showed me was a newer vacuum assist pump for the braking system that's very quiet from EVComponents. It's a bit expensive, but the pump produced very little noise, even with the hood open and my hear near it. Also, to enhance the power steering, they use the electric power steering pump from a Toyota MR2 so that parallel parking isn't as hard. More info here.

So far, the new controller is doing just fine. It also got bumped up to 700 motor amps from 600 when starting from a stop. The tires do a wonderful little "chirp" when I floor it from a stop in first gear before the batteries current maxes out at 300 amps. I could kick both of those up, but choose not to so I can save breaking my transmission and batteries.

I'll try and keep y'all posted on the progress. I'm a bit tired of working through issues right now, so if the car drives well, you might not hear from me for a few weeks.

One other complaint I received was that the open-source Civic plans were not complete on the Civic-EV Google Group. The complaint is valid and I plan on finishing things when the summer is over and I'm past my burn-out stage on this project. I hope to just enjoy driving the car for awhile. The modified charging circuit seems to be doing its job well and I'm happy that problem is over.

In the meantime, I'll be attending the Wayland Invitational at PIR to rub shoulders with the bigwigs in the EV industry at the end of July.

EV Awareness Day, Synkro faults

2009-07-12T09:10:00.001-07:00

Yesterday was our local EV organization's big annual event called EV Awareness Day. We held it at Pioneer Courthouse Square in downtown Portland. I gave a press event with the Mayor Sam Adams and two VPs from local power companies (PGE and Pacific Power).

Probably one of the coolest things about the show is that a Tesla Roadster showed up unexpectedly!

Here I am with the Tesla Roadster.

After talking about electric vehicles to people all day in the sun, I was rather fried at the end of the day.

On the way home the Sykromotive controller faulted three times during initial acceleration up a hill in the summer heat. I suspect these are temperature glitch faults that Synkromotive has been having issues with for awhile. Being fried from the show and caught in heavy traffic on a hill with lines of people behind me, you can imagine this wasn't much fun. Fortunately, I've learned that I just need to toggle to ignition key and wait five seconds to try again.

After clearing the third fault on this hill, I was able to very slowly accelerate up the hill until the motor turned enough to not cause noise issues with the temperature sensors in the controller. I'll be uploading all the fault logs soon and contacting Synkromotive for further advice. Other than the temperature faults, the controller has been excellent. This is still a "beta" unit, so perhaps they've resolved the issues. Let's hope so...

Super FET working Comments on Sykro Controller

2009-07-09T17:40:00.000-07:00

Last week I was mostly on vacation, so I didn't get a chance to really charge the car at full amperage many times. This week was back to work, so I was able to give the charge detector a more reasonable test.

In short, the three huge FETs with heat-sinks seem to work just fine (I should hope so...). I've charged the car seven times in the summer heat and the charger can dump a full 8 amps into the batteries every time without heating up the charge detector box.

I had a little bit of a scare today at work. The Synkromotive controller would instantly fault every time I touched the accelerator. It seems that I had a loose connection between the potbox and the controller. When I wiggled the connector on the TPS (throttle-position-sensor), the controller ceased to go into a fault condition and I drove home. I put anti-corrosion compound on the TPS contacts to help prevent a similar fault in the future. I'll bet that the Sykromotive controller was faulting due to an incorrect input on the potbox wires.

I really like the simplicity of the system. If it fails, it usually fails big and the failure is usually a loose wire somewhere. Get out your Fluke-meter and start debugging.

On my last post, someone left a comment asking about how well the Synkromotive controller was working. In short, it's great. It gives a lot of power when requested and is quite easy to tune various internal parameters through the user-interface over the USB port. Embedded logging makes it really nice as well.

A few nitpicky items I would improve about the controller: The large bus bars that attach to the battery cables are mounted vertically, requiring the use of right-angle lugs or fancy routing of wires. Also, the power given to the motor instantly reflects whatever is specified on the potbox.

If you have a quirky potbox or press the accelerator too quickly, the car seems to lurch a bit. This is especially true if there is slack in the drivetrain from having the motor coast to a complete stop. The lurch instantly takes up the slack in the drivetrain and you can get a jerk that might cause oscillations.

As I've mentioned before, the big solution to this is to use the factory TPS instead of a cheap forklift potbox (like a Curtis PB-5 or PB-6). The factory one is much smoother and more reliable. The downside of the factory potbox is that it never goes to zero ohms which means you can't use it for simpler controllers like a Curtis. The Synkromotive controller has many potbox tuning adjustments so you can set the zero point and the acceleration ramp depending on the travel distance of your throttle cable.

The Synkromotive controller on hot days sometimes gets a temperature noise fault. More recent firmware tends to fix this issue, but I've still stalled once with the latest firmware. Fortunately, you simply need to toggle the ignition switch and wait four seconds for the precharge circuit to run to re-engage the contactor before driving again.

This weekend is the biggest day of the year for our local EV club. We're showing off 30 electric vehicles in Downtown Portland and Mayor Adams is also showing up at our press event to endorse our group. I'm excited but will be happy when it's all over.

Time to Get a Larger Hammer

2009-06-25T17:33:00.001-07:00

After two days of running perfectly, I found yesterday morning that the amps were down and the FET had blown again. This really stumped me because I thought I had done everything to keep it cool and out of the switching region.

After showing the system to the power supply EEs at work, they told me that any FET in a TO-220 case like the one I had would not handle a constant 8-amps for a long time. The heat dissipation comes from the bond wires going to the silicon inside, not the actual silicon itself. They suggested that I put multiple FETs in parallel to lower the resistance and spread the heat over multiple sets of FET bond wires. If you can lower the resistance by half, the power dissipation goes down by a factor of four.

As you might imagine, I'm getting really tired of blown FETs, so I rummaged through our lab stock and got the biggest FET I could find.

Here's a comparison of the FET's I'm using. Instead of one TO-220 case FET on the left, I'm installing THREE of the TO-247 case FETs on the right in parallel with heatsinks. I'll be taking the "on" resistance from 30 milliohms down to 3 milliohms. By dropping the resistance by a factor of 10, I can theoretically lower the power dissipation by 100 (I^2*R from ohms law).

Here are the three high-power FETs installed inside the charge detector box. Note the burnt spot in the lower right corner of the printed circuit board from the smaller, individual FET that burned up yesterday morning.

I just started charging with this new circuit about an hour ago. The charge detector box is COLD. I can barely feel a slight temperature difference between the top of the box and the vehicle chassis.

Some might think this is overkill. Those folks would be right. It probably is, but I'm sick of wasting my own time and the time of all the folks at work who are graciously helping me out. I would rather nuke this one with an overdesigned system instead of having to revisit it several times.

Here's a third schematic (click to enlarge) including the changes to Q1, Q2 and Q3 FETs on the right side.

I sure hope this issue is dead. I've got a few EV shows coming up and I'm done with dealing with this issue. Let's see what happens. Hail Mary.

Cautious Optimism

2009-06-22T19:15:00.000-07:00

After talking with the power supply EEs at work, I came home and tried a few experiments to see if I could fix the alternative charge detector circuit.

First, I used an external 12V UPS battery instead of the AUX power output on the Belktronix charger to see if noise on the power supply was causing my problem. Nope: The circuit still behaved as if the opto-coupler latched closed.

Next step was to pull out my oscilloscope and start probing around the system. Fortunately, most of the battery pack and components are floating, so I can attach the ground of the scope to several different high-voltage points to serve as a reference.

Yowzers! There's a hell of a lot of noise in this system. Whenever the Belktronix charger starts up, I get 50V spikes at ~200Khz on the oscilloscope by just holding the tip of the input probe with my finger. Keep this thing away from your pacemaker! I'm guessing that these high voltage noise spikes are causing problems with the opto-coupler.

Here's a modified schematic. The EE folks at work suggested adding C4 (.01uf cap across the opto-coupler input) to help cut down on the noise. I also reduced C3 down to 10uf from 47uf. This reduction increases the maximum switching frequency for the FET (due to the hysteresis in the 555) from 1Hz up to about 5 Hz. While the FET switches at a slightly higher frequency, it's still so slow that the FET stays out of the linear switching region for long periods of time.

I plugged in the system and (gasp), the FET stayed on like I intended it to. After suspiciously pondering the circuit thinking that I had messed something up, I shorted out the OVP signal and the FET quickly turned off and the LED came on. The link-10 meter shows a full 8 amps going into the batteries. In a few hours, the BatMon boards should start lighting up and I'll see if the circuit responds correctly. The charge detector box is a bit warm to the touch, but definitely not hot.

I'm very excited that adding a .01uf capacitor to the opto-coupler input cleared up much of the noise. Someone over in the UK had their Belktronix charge detector blow up too with a lithium ion battery pack, so I hope this circuit can help them too.

After my heated rant last night, I received several supportive e-mails and comments from people. Thanks to all who responded for your ideas and well wishes. I feel good when I hear from folks because I don't know how many people are actually keeping track of this blog, especially since things have quieted down recently.

Let's keep our fingers crossed with cautious optimism. Cheers.

Failure Again!

2009-06-21T21:32:00.001-07:00

I came home this evening after a 20 mile drive with excitement to see the new charge detector circuit work. I plugged in the car and the circuit had an interaction with the optocoupler on the BatMon board and didn't see the correct signal. Nothing is burning up, but the FET is stuck in the off state for now, leaving the system to charge slowly with a really hot 3-ohm resistor.

I'm so angry at this charging system! It's a good thing I just got back from my mindfulness meditation session or I would throw a wrench at the car. God, I'm pissed! It worked so well with the batteries near a full condition, but the circuit fails when the batteries are discharged. I suppose this is a good data point for further analysis, but I'm rapidly running thin on patience.

I'm taking the circuit into a bunch of EE experts tomorrow at work (they always like working on these problems instead of their real jobs) and we're going to get to the bottom of this. I'm running out of energy to get this working. Damn, this sucks.

A New Hope

2009-06-21T13:57:00.001-07:00

After the utter failure of the Soneil and the Joule chargers, I did some more research on individual battery chargers. Ideally I was looking for the following:

Power factor corrected
Weather-proof for mounting under the hood
Isolated to work with a series pack of batteries
6-8 amps charging capacity
low power enough to put all 12 chargers on one 15 amp circuit (possibly 20 amp circuit)
somewhat affordable

I did some more searching and found the BatteryMinder 12248, the Xantrex Trucharge 10, and the Waeco PerfectCharge IU1012. The Waeco units seemed really good but were from Germany with no distributors in the USA. The Xantrex and BatteryMinder units were $150 apiece (ouch!) and didn't meet all the criteria above.

I decided to go back to the drawing board and see what I could do with the Belktronix charger. In concept, the charging system was great. It's a nice power-factor-corrected series charger that dumps out a solid 8 amps and it's sealed so that bugs and dirt don't get in.

Since I've moved to the Synkromotive motor controller, there aren't any more mid-pack taps off the battery pack, so the batteries tend to drift out of balance more slowly. Arguably, the resistive shunts with the Belktronix charging system should be able to handle this quite well.

The problem in the past has been the charge detector. Without going into all the details of operation, the OVP lines from all the BatMon modules would pulse and cause the FET inside the charge detector to turn on and off. Since this pulsing was frequent, the FET was often in the switching region and easily overheated.

The FET inside the charge detector determines if the large 3-ohm 180-watt series resistor is inserted in the charging circuit. If the FET is on, then the 3-ohm resistor is shorted and the batteries get a full 8 amps, which is great for fast charging. This brings up a problem when the BatMon boards detect a "full" condition on the batteries. The small 3-ohm shunt resistors start to burn up if they have to sustain the 8 amp current flow. Thus, the charge detector needs to turn off the FET to insert the large series 3-ohm resistor to limit the current. If you turn off the FET too early, it takes forever to charge your batteries and the large 3-ohm series resistor gets really hot. Turn off the FET too late and all your shunt resistors burn up, causing massive smoke and potential fires in your EV. (ugh)

Here's a picture of the inside of the blown charge detector. The FET is clearly blown in half with burn marks all the way around it. Note the melted region on the case cover in the lower right.

The FET in the charge detector is a very good one with a very low turn-on resistance. If we can limit the amount of FET switching and turn it on/off hard to keep it out of the linear region, it should stay relatively cool, even with 8 amps flowing through it. So, I put on my EE hat and designed a completely new circuit to put inside the charge detector box.

Here's the charge detector box with the new circuit inside of it. The circuit (shown at the end of this post) uses the comparators and flip-flop inside a 555 timer (Radio Shack special!) to drive the FET with hysteresis on the input to limit switching.

Here's my old Radio Shack 555 timer handbook. It's a crying shame they don't sell these anymore. I guess it doesn't make a profit and people just aren't into dinking around with 555 timers anymore. As you can see (click to enlarge picture), this tiny chip contains two comparators, an RS-flop and an output driver. This is just what we need to observe the pulsing OVP signals from the Batmon boards to determine if we should turn the FET on and off to short the large 3-ohm series charge resistor.

I tend to go overboard with these things. This is my kitchen table with all the soldering/test equipment on it.

Here is the simple circuit I put inside the charge detector box to control the FET that shorts out the large 3-ohm series charging resistor. Note that this lacks a few safety features that would prevent a blow-up if the user hooked things up in reverse, so this is not a product-worthy circuit. It's simple enough and you can get most of the parts (except the FET) from Radio Shack. If you click to enlarge the picture, you can see the theory of operation and get more details.

I'm going to try this out for a few days and see if I can charge faster without blowing up the FET. The potentiometer still probably needs adjustment to properly set the duty-cycle detection on the OVP pair, but this is a good start. If this works, I'll have fast charging without setting the small shunt resistors on fire. Here's to hope...

A Very Dark Day with the Joule Chargers

2009-06-19T10:31:00.000-07:00

This whole experiment with the individual chargers has been a very humbling experience.

After the whole set of failures with the Soneil chargers, I learned from the distributor that the 1214S model doesn't support series strings of battery packs:

Tim,

Well, based on this email I sent an email to Soneil. Apparently there has a
been a design change in some of their chargers (these included) which
prevents you from being able to charge while in a "series" configuration.
This means that the half with no LED are dead. This also means you can't use
that charger type with that configuration. I apologize for this huge
inconvenience, I have no idea why they would change the design. The closest
12v Soneil charger we have that does not have this design change is the
1212SR, but it is a 5amp and is $89.95ea. We can refund your order or
replace the same value with 1212SR chargers, I'm not sure what else to offer
you. Both issues you have found have been somewhat unbelievable, I apologize
for the "luck" on this. For the electric bike application, both charger
types work great. The electric car application has a few unexpected
differences....

Thanks,
Mike (from ElectricRider)

After hearing the above, I returned the Soneil chargers and asked ElectricRider to ship me a set of their in-house Joule chargers (model JJ12060). Their technician insisted that the chargers should be fine for a series connected battery pack.

About a week later, the box full of Joule chargers arrived on schedule.

Here's the pile of twelve Joule chargers after I stripped off some insulation and added ring terminals for the batteries. I'm really excited because these are smaller than the Soneils and have integrated cooling fans. Despite the 35-40mA current draw, I'm full of hope that these will solve my pack imbalance issues.

After installing several of the chargers, I observed the following:

One failed to even start up (LEDs were flickering)
Six didn't have their fan come on. I thought that the fan might come on after the charger heated up, so I left one on for 20 minutes. The unit overheated and ceased to work. One of these six had its 100% charged LED stuck on, possibly indicating other issues.
Five powered up correctly; however, the fan on two of them seemed to get up to speed very slowly, possibly indicating fan bearing issues.

In short, I'm very disappointed with these chargers. They have a one-year warranty, so I could send the bad ones back for replacements. I purchased thirteen of them, assuming that one would be bad. The > 50% fallout rate greatly concerns me. In addition the PFC (power factor correction) value for these chargers is about 0.6 which roughly means only 60% of the input power gets to the battery and the other 40% gets dissipated as heat in the charger. No wonder these things get so hot!

I'm taking a day to ponder my alternatives. The Belktronix charger has a lot more "spaghetti" to it as well as hot shunt resistors. On the flip side, it has a very high PFC value which means that the primary charger is quite efficient and it doesn't heat up much. The charger is also sealed, making it much more resistant to dirt and bugs.

One option I'm considering is replacing the shunt resistors on the Belktronix charger with 50-watt halogen light bulbs. This means some of the shunted energy gets converted to light instead of heat. I'm also looking into a circuit to replace the charge detector in the Belktronix system.

EV Awareness Day here in Portland is only three weeks away and I've got to get this beast charging correctly. Here's to being stubborn. Stay tuned.

Sleuthing the Soneils

2009-06-07T06:36:00.000-07:00

Against my better judgment, I took apart one of the failed Soneil chargers yesterday afternoon to see if I could find out anything about the failures. There weren't any burned components or obvious damage. After powering up the unit with the cover off, I could verify that the isolation transformer between the AC side and battery side wasn't getting pulsed, and thus passing no power to the battery (or the LED). It seems that the UC3842A chip DC-DC converter chip used to drive the FET which pulses the transformer was dead. It's power supply had a resistance of about 3 ohms to ground (bad).

After mulling over the circuit in my head last night. I tried to compile a list of facts I know about the failure:

Facts:

The batteries were all fully charged in the morning, despite the charger failures
The batteries with working chargers had ~13.7 volts on them, the failing ones, ~13.4
There were far more failures in the batteries in the front of the car
The front batteries are closest to the negative pack voltage
I plugged in the rear batteries first when testing the chargers
The rear batteries typically have slightly more charge on them because they get warmer
I started all rear battery chargers simultaneously on a power outlet strip
I started all front battery chargers one-by-one by plugging them into power cords with three outlets on the end
The components crossing the isolation barrier in each charger are: a transformer, an opto-isolator, and three ceramic capacitors (.01 uF at 250V)

Hypotheses:

Since all batteries were at nearly full charge, the failure must have happened at the end of the charge cycle, perhaps when the charger transitioned from acceptance charge (14.7V at 3.5A) to float voltage (13.7V)
Since the front batteries typically finish charging last and I also plugged them in last, perhaps a surge from the rear battery chargers (when shutting off) caused failures in the front battery chargers
Is suspect that the capacitors at the isolation barrier in the chargers failed because they have a breakdown voltage of 250V. When charging one battery, this is fine. When charging a long series string of batteries (oh, say, 144V), the charger output stage can float +/- 144V relative to the AC voltage on the input stage. 120V AC really becomes 170V DC when rectified. Add this to 144V and you get 314V, which is clearly above the 250V rating in the isolation capacitors.

Based on this, I don't think sending the chargers back for replacements would really help the situation. If all the chargers have the same 250V isolation caps, then they would all fail eventually. I suppose I could take all the chargers and replace the isolation caps with similar values but give them a 1KV voltage rating.

I'm trying to figure out the best option for now. To drive the car, I'll probably need to re-install all the Belktronix resistive shunt balancer modules. The car would be driveable but it would still take a long time to charge. I don't like the idea of hand-modifying twelve Soneil chargers, but that would probably be what it takes to get them working.

I could send all the Soneil's back and get the Joule chargers again. That is, after checking with the designer that they support 1KV of isolation. The Joule chargers draw 35mA of current when sitting there unplugged. This hypothetically translates to 2857 hours of discharge from 100Ahr batteries or about 4 months until the batteries are completely dead. If I went on a long vacation, I guess I would leave the chargers plugged in on float charge anyway. The Joule chargers also only charge with 6A, which means (despite a bad PFC rating), I might be able to plug in all chargers to a 15 amp AC circuit (The Soneils pull about 18 amps for all 12 chargers).

This is a really bad time because we have so many electric vehicle events happening now. Having a dead EV is not too appealing. I'll ponder this for a bit.

Happy Sunday morning.

A dark day with the Soneils

2009-06-06T10:18:00.000-07:00

This morning was a dark morning.

I received the Soneil chargers yesterday around noon and stayed up until 11:30 last night to install them. After installation, I powered them up and all chargers lit up with an orange LED. Yay. This morning, I got up and half of the chargers had a green lit LED and the other half were dark. I used a Kill-a-Watt meter to determine that the dark units were pulling no current at all.

I've heard rumors that Soneils don't like to be attached to a series pack.

It looks like my EV is dead for the near term. Putting the Belktronix system back in with all of its shunt resistors and battery boards does not sound appealing right now.

Ugh.

Fixing the Potbox, Soneil's Arrive

2009-06-05T12:39:00.000-07:00

Over the past few days, the car has still been lurching around despite the potbox parameter adjustments that I've made inside the controller. I contact Bob Bath, the original CivicWithACord builder who sold me my PB5 potbox. It was brand new from KTA Services and not used/worn-out. Yesterday in stop-n-go traffic, the car was lurching again and the controller faulted when I haphazardly floored the accelerator with the car out of gear. After expressing my frustration, Ives at Synkromotive highly recommended that I install the factory throttle position sensor (TPS) from the original Civic instead of using the PB5 potbox.

Here's the factory Civic TPS installed. I mounted in the same place as the PB5 potbox, but used a piece of 1.5" angle iron 4" long to mount it. Unlike the PB5 which only has two wires, this TPS has three which allows for higher reliability and more accurate signalling to the controller.

Here is the rear side of the installation. You can see the top of the grey-painted angle iron that I bolted to the engine mount side. I had to chamfer one corner to prevent interfering with the engine mount rubber. The actual electrical potentiometer is black at the far left of the picture, while the cable attachment is on the far side of the large butterfly intake valve. There were some extra bolt holes in the throttle housing, so I just used a piece of all-thread and bolts to suspend a small piece of 3/4" angle iron to support the fixed point on the throttle cable.

After a test drive, the system was sooooooo much better. I can creep forward with the car now and the lurching is gone except when I really stomp on the accelerator. I'm now completely convinced that the PB5/PB6 potboxes are complete crap compared to the factory throttle position sensor. It's too bad the TPS doesn't go down to zero ohms, so it can't be used for many other controllers like a Curtis.

After I arrived back home from the test drive, the FedEx truck showed up and dropped off 13 brand new Soneil 7amp chargers. I've been waiting for these for over a month now and am happy they are here. This will replace the Belktronix charging system and allow me to remove all the spaghetti associated with the shunt resistors and battery monitoring boards.

This is a good day. The car is running smoothly again, and I'm psyched to get these new chargers put in. Have a great weekend everyone.

Cheers, Tim

Moving the Instrumentaiton

2009-05-31T16:48:00.000-07:00

Since the Synkromotive controller has its own motor speed limiter based on input directly from the Zolox sensor, I decided to clean up the instrumentation by removing the RPM gauge and moving the Link-10 E-meter onto the dashboard. While this removes some of the "coolness" factor without a tach, I like the more simplistic look as I tend to be a minimalist.

Here's the empty pillar pod with the gauges and wiring removed. I'll probably run the local Civic used-parts store and simply get a piece of replacement trim.

Here's where I moved the E-meter to. I can actually see it quite well when driving. It's sitting in the same hole where the defroster button used to sit. I simply carved a rectagular hole in the dash and moved the defrost switch down a few inches. It protrudes a bit, but still works fine.

In addition to moving the gauges, I wired up the "oil" light to the warning light on the Synkromotive controller. The oil light requires it's input wire to pull down to ground. Since the motor controller puts out a +12V signal when there's a fault, I used a simple transistor circuit (see the schematic at the end of this post) and drove the transistor gate through a 3.3K ohm resistor.

Synkromotive Potbox Issues and Temperature Faults

2009-05-31T16:33:00.001-07:00

Over the past week, I've been able to give the Synkromotive controller some good real-world experience during my commute. The controller is very smooth and has several parameters to keep the battery pack healthy. I also like that the Synkro controller doesn't tap off the main pack for part of its power supply which has led to pack imbalances in the past. You can see several voltage-current graphs on the Synkromotive website here. Click on SynkView at the bottom. You'll have to install MS Silverlight to see the graphs. Click on Logfiles/Civic and then an .XML file on the right to see various drives.

One major issue I had was that the car tended to lurch when first starting up. This isn't too bad on the freeway, but can be a real pain when in stop-and-go traffic. Last Thursday I was driving home in hot weather in stop-and-go traffic on the freeway in the middle lane. The car seemed to get progressively worse during the drive home with its "lurch-starting."

About 2/3 of the way home, the controller faulted and just stopped the car dead in the middle of the freeway. I attempted to clear the fault and get the car started again by turning the ignition key off and on. I must have been impatient (sometimes it takes a full six seconds for the controller to precharge and be ready), but I wasn't able to clear the fault. Traffic was slow, and two kind men helped me push the car off the left side of the road. This was a somewhat unnerving experience, but I guess it's part of the game when trying out a Beta-test motor controller. After propping open the hood, removing the primary 12V power from the controller and hard-booting it, it seemed to start up again and I drove the rest of the way home.

The beta controller units have been having a few issues with noisy temperature sensors. During initial acceleration, the electrical noise tends to cause a spike in the temperature sensors, causing the controller to shut down. After I got home from this incident, I observed some of the potbox inputs (Ainput in the Smi window) and realized that I have a really crummy PB5 potbox. The resistance goes from zero ohms and jumps up erratically to 400 ohms or so and then goes smoothly up to 5K. With this new information, I was able to set the "zero throttle" point above the 400 ohm point which makes acceleration much smoother and bypasses the glitches in the potbox.

Yesterday, I was driving someone home in the Civic. Again, it was a hot day and we were in stop-and-go traffic. The controller faulted again and shut the car down. Fortunately my friend, who was in a hurry, could walk the remaining eight blocks home while I rebooted the system. Ives at Synkromotive gave me some updated firmware with some extra noise filtering on the temperature sensors. After running the car through the same route with the new firmware and doing some extra stop-and-go testing, I couldn't get the controller to fault again. We'll see what happens the rest of the week.

Despite the faulting condition, I've been extremely happy with the power, smoothness, logging and programmability of the Synkromotive controller. This is going to be a really good product when it hits the shelves in July.

Going to the Electrathon/HPV Event at PIR

2009-05-31T16:27:00.000-07:00

Last weekend, I took the Civic-EV to Portland International Raceway to show it off at the Electrathon/Human-Powered Vehicles event there. Memorial Day weekend is the one weekend that PIR can't make any loud noises, so they actively recruit electric vehicles and bicycles of all types to race.

Here's Gary's Honda Insight EV with lithium ion batteries and an Siemens AC motor.

This shows some of the velomobiles (encased recliner cycles) present at the event. They really fly.

Here's my humble Civic next to Paul B's Corbin Sparrow.

It was really hot that weekend, but the new controller held up well on the freeway.

Installing the Synkromotive Controller

2009-05-23T00:02:00.000-07:00

I stopped by the Synkromotive shop this morning and picked up my beta-test controller that I've been wanting to try out. After running out and buying some more magna lugs and welding cable, I came home and removed the Belktronix controller and all the associated wiring.

With the old controller gone, I had to figure out how to place the new contactor and controller. Here's my mock placement. I placed the contactor slightly behind the controller to limit the cable lengths I would have to use and keep the high-voltage connections away from eager fingers. After the placement, I removed the piece of thick plastic below, drilled some mounting holes and bolted the controller and contactor in place.

This picture shows all the high-voltage 2/0 gauge cable hooked up. I was very fortunate that I could reuse all the old cables and simply crimp on new lugs. My purchase of 12 extra feet of 2/0 gauge cable was for naught, but I'm glad I got it anyway since the welding shop is only open on Friday.

The high-voltage connections on the Synkromotive controller are well thought out, especially if the controller is near the motor and parallel to it. The funny downside is that the connector bars are vertical instead of horizontal, forcing me to use less-common "L" lugs on the 2/0 cable to attach things. I'll have to give this feedback to Synkromotive.

Here's the preliminary installation. I don't have the motor RPM sensor hooked up yet, but I wanted to get the system going because there's an electric car show this weekend at PIR (we're demonstrating EVs along side the Electrathon and Human-Powered-Vehicle folks).

The Synkromotive controller is fully digital and has a USB port on the side. After firing up the user interface program, I was able to verify that everything was mostly operating. Given that this is a beta program, documentation is slim at best and full of bugs. I've already given much feedback regarding specific points in the document that cause confusion.

After checking all the voltages, I rotated the potbox by hand with the transmission in neutral and (Voila!) the motor spun. As of 11:30pm, I took it for a quick test drive around the block. The acceleration was very smooth; however, it wasn't as peppy as I had hoped. The amps never got above 150, so I'm guessing there's some calibration I need to do with the potbox. Anyhow, after 7.5 hours, I successfully swapped out the old controller for the new.

I'm a big fan of an uncluttered engine compartment. While the Synkromotive controller definitely has some wiring, the Belktronix system was a bit more out of control. Here's a bunch of the "spaghetti" that I removed with the older controller. I like seeing the removed chaos in a box.

Once I get the individual Soneil chargers, I can remove additional wiring and clutter without all the shunt balancer boards on top of each battery.

Whoosh, I'm liking this new controller! Tomorrow I'll tweak settings a bit more and see if I can take it on the freeway to PIR for the show.

Cheers,
Tim

Installing a New Potbox

2009-05-17T21:05:00.000-07:00

As with many EV projects, much time is spent waiting for parts. The replacement Soneil chargers haven't shown up yet. On a more positive note, Synkromotive figured out some of the glitches in their new beta controller, so one should be available this coming Friday. This new system will require a different potbox, contactor and other wiring.

I'm excited to install the controller, so I installed a new potbox to get ready.

Here is a view on the driver side in the engine compartment just above the engine mount. I'm going to use the two holes in the engine mount bracket to mount the potbox.

Here's the PB-5 potbox that I purchased from Bob Bath with an aluminum bracket bolted to it. I was fortunate enough to keep this around in my pile of parts because it fits very well.

Did you notice the shiny silver thing attached to the arm of the potbox above? I had difficulty trying to figure out how to attach the acclerator cable to the arm of the potbox. The guy at the hardware store suggested that I use one of these tiny cable clamps. The "U" bolts fit perfectly in the holes on the arm and I can clamp the cable down tightly.

Here's the potbox mounted in place. Notice how it's tilted slightly to the left and not in parallel with the E-meter DC-DC converter in the black box to the right. This is because the accelerator cable interferes with the top of the shock tower if the potbox is mounted inline with the car. This leftward tilt moves the cable just inside the shock tower so it hangs better.

Not only did I have to attach the acclerator cable to the potbox arm, but I needed to mount the housing on th end of the accelerator cable in something so the cable could pull against something. To accomplish this, I took a spare piece of 3/4" angle iron and drilled a 5/16" hole in one end, near the edge. I then cut out the hole with a hacksaw to get this keyhole-like shape. This will allow the cable housing to slide in at its narrow point but not pull out when I slide it forward so that the wider threads sit in this 5/16" hole. I also drilled a 3/16 hole in the other angle iron face to mount this tiny piece with an 8-32 by 1/2" bolt.

Here's a piece of flat bar that will hold the cable housing. The two holes on the left are the same distance apart as the two posts on the potbox. The hole on the right end is where I'll mount the tiny piece above so the cable has something to push against.

After sawing off the tiny piece from the end of the 3/4" angle iron, I mounted it to the flat bar with an 8-32 x 1/2" bolt and nylock nut to keep it from falling off. This will rotate a bit and allow the cable some play as the potbox arm swings back and forth.

Here's the above bar mounted to the potbox with 8-32 x 1/2 button-head bolts with lockwashers.

Here's the same picture above, but with the cable mounted in it. The trick is to get the bracket on the right in the correct place so that you can use the two adjusting nuts to properly tension the cable so it gives maximum throw and stops at the zero point on the potbox.

Stay tuned for Friday when, hopefully, the controller arrives.

Researching a Paint Job

2009-04-18T09:58:00.000-07:00

One of the downsides of a home-EV conversion is that most of them don't have air conditioning. The AC tends to suck precious power from the battery and adds extra weight to the car while taking up space that could be used for batteries.

Thus, it's often best to get a white (or light colored) donor vehicle to repel the sun's rays during the summer. The conversion vehicle I purchased is dark metallic blue, which get's really hot inside, even on a mild day in the sun.

So I called a bunch of different car painting places to determine the cost of painting the car white. Much to my dismay, the places that got good local reviews wanted at least $3500 to paint the car. The local Maaco paint shop (which got horrible reviews) wanted $550 for their bottom-of-the-line paint option.

In short, I guess I'll be rolling down the windows and using a reflective shield under the glass for the near future. Note to self: purchase a white conversion car next time...

Planning to Replace the EV Components

2009-04-18T09:33:00.000-07:00

In a month or so, I'll be getting a beta-test motor controller from Synkromotive which will have a variety of programmable features as well as more power. Since I'm replacing the controller, I looked into replacing the other components with off-the-shelf items that might work better than the current Belktronix system I have.

Here's the plan:
- replace the controller with the programmable Synkromotive unit
- replace the optical potbox with the original Civic TPS (throttle position sensor)
- replace the charging system with a bunch of individual chargers (Joule or Soneil)
- replace the integrated DC-DC converter with an IOTA DLS-45 unit

Here's a picture of the IOTA DLS-45 DC-DC converter on the right that I purchased at Northern Arizona Wind & Sun for about $150.

On the left is a jj12060 Joule individual battery charger from ElectricRider, supposedly modelled after the popular Soneil chargers. I purchased 13 of them, 12 for the batteries and one extra in case something dies or I need to charge an external 12V battery. They were out of Soneil chargers and said that the Joule was a drop-in replacement with the same specification (right!).

As is typical, things didn't go as planned. I saved this weekend for removing the old charging system and installing the Joule chargers. As a safety check, I clipped a Joule charger to one battery to observe its behavior. When I attached the charger, I heard a click (like a relay) from inside the charger. Hmm, if the battery is always powering an internal relay, then there's a constant current drain (that's bad).

I checked the current draw with an ammeter and found that the Joule charger pulls 35ma out of the battery when it's just sitting there! The Soneil chargers have the feature of not pulling ANY current out of the battery when attached but not plugged into the AC source.

In short, the Joule chargers are NOT a drop-in replacement for the Soneils and I'm going to return them and get Soneils instead.

Argh, more delays. At least the weather outside is beautiful and I can go for a hike.

Have a great weekend everyone.

Taking a Vacation

2009-04-18T09:24:00.001-07:00

It's been over a month since I've blogged about the Civic and people have started to ask where I've been. I'm still commuting (even with a blown charge detector) and the car has 1500 miles on it. Several events have happened with the Oregon Electric Vehicle Association (of which I'm the Chair) and I also went on vacation.

At the end of march, I went on an amazing backcountry adventure, skiing the Wapta Traverse with a 45 pound pack on with Randonee' skis.

Here I am near the start of the trip. The scenery was mind-blowing.

Here's the group all roped together just behind an enormous crevasse, heading up to our high-point on the trip. The picture just doesn't do this justice.

Now that I've recovered from the trip, I'll be getting back into trying to fix the charging system.

Stay tuned.

Charge Detector Blown Again

2009-03-12T18:08:00.000-07:00

A few days ago, something funny happened to the vehicle. I drove home and my LVP light came on earlier than I expected. When I got home, the front battery was rather lower than the others in the pack. I attributed this to being just behind the front grille where a lot of cold air is blowing in. to remedy the problem a bit, I slide a large sheet of foam-core board between the batteries and the radiator grille which gives a bit of insulation and forces the air go around the side.

After measuring my batteries for several days after that, they seemed much better, but still didn't seem to get fully charged when sitting at work. Again, I attributed that to the low temperature around here (mid 30's).

Today, I drove home, plugged in the charger and just checked to see if the charge detector was working. Sad to say, the FET has probably blown open again since the OVP lights were not on and lots of current was dumping through the large external 3-ohm charging resistor, making it really hot. This would definitely explain the slow charging.

After trying to fix this device several times, I have a few options:

- fix it again (and wait for it to blow again)
- send the charging system back to Belktronix to get upgraded to a Gen2 system without the charge controller for about $400
- dump the Belktronix system altogether and go with something else, like individual Soneil chargers (Rob Connelly did this and is happy with the results)

I'm not sure what I'm going to do. The existing charger works, but it's just a bit slow. I'll ponder this over the weekend. I have an OEVA meeting to lead this evening.

Ugh,
Tim

1000 Miles and Still Going...

2009-03-07T09:59:00.000-08:00

There's not too much to report on the Civic. I just passed 1000 miles yesterday and it still seems to work fine. I've definitely noticed over the past several weeks of commuting that my range is highly dependent on my speed. Even driving at 55mph instead of 60mph on the freeway gives me a few extra percent of battery life on the Link-10 E-meter.

I've ended up driving with the LVP protection disconnected from the Belktronix controller because it tends to make my speed go way down even though I have plenty of battery left. The LVP circuit is still attached to the battery light on the dash, so I know when to start being very careful of my driving habits.

The charging system seems to be working fine now that I have the BatMon boards inside boxes, protected from the elements. I've driven in a hard-driving rain several times without any problems. The final voltage on the batteries differs slightly from battery to battery due to the analog nature of the Batmon circuits. The BatMon boards rely on the calibration and tolerances of analog components to activate the shunt resistors at 14.5 volts or so.

I'm starting an experiment with several prototype digital battery monitoring boards from Synkromotive. I'm going to see if I can determine which battery is causing the LVP fault earliest with this monitoring system. For you circuit geeks out there, the Synkromotive system (prototype only at this phase) has a 12-bit A2D converter which makes it more accurate than the PakTrakr system used in many EVs today. Those extra bits can make a big difference when your batteries are close to the end of charge and the balancing system needs to compensate for small differences like 50mV. The digital nature of the system (each battery gets an 8051 microprocessor) allows for easy adjustment of calibration values in case things drift over time.

I'll report back when I get some more results.

Cheers,
Tim

EV Driven Link

2009-03-07T09:55:00.000-08:00

A few weeks ago, I added an "EV Driven" link to the right menu bar of this blog. EV Driven is a group of folks trying to spread the word about EVs and are behind the upcoming movie Revenge of the Electric Car. It contains several searching features for this blog as well as many other blogs related to electric vehicles. Please check it out when you get the chance.

Cheers,
Tim

Fixing the Charging System...Again

2009-02-12T17:42:00.000-08:00

After doing another fix to the Charge Detector box on Monday, I enclosed all the BatMon boxes to prevent them from shorting out due to grime and automotive fluids.

Here are the plastic boxes I talked about in a prior post. They are held in place with velcro adhesive tape and the box lids are held together with red electrical tape. I don't seem to be having any trouble with overheating (yet...) and the clear plastic lets me see the OVP/LVP lights.

This has been my third week of commuting and I've got 550 miles on the car. It's been fun to drive and show off. I sold my other EV (Porsche 914 at 914ev.blogspot.com) last Sunday, so I'm glad to not have three cars to deal with and the associated insurance.

I'm going to take a break now and just enjoy driving the car, hopefully without too many charging issues. About a month from now, things are going to get interesting again because I'll be trying out a beta test controller from Sykromotive. It's much more programmable, so we'll see how it goes.

Have a great week, everyone.

Thoughts on the Kit and Belktronix System

2009-02-04T09:21:00.000-08:00

With 350 EV miles on the car, I'm ramping down on fixing things and ramping up on commuting. Before I forget all the stuff I've learned, I'd like to capture some thoughts about the Open-Source kit and my experience with the Belktronix system.

Good points about the open-source Civic-Kit:

I really appreciate keeping the clutch. It makes shifting much easier and makes the car feel like a regular vehicle
Choosing AGM batteries was a great idea. No hassle with plastic boxes and they put out a punch of current. No acid spill either.
The kit involves no welding (metal or plastic)
There's no cutting of the chassis to attach parts or install batteries, only drilling holes
The kit keeps the spare tire and quite a bit of trunk space while still seating four people
Choosing the 5th generation Civic was a good choice for curb and gross vehicle weight. It is also simple to tap into the gauges and electrical system since it's before the advent of complex CAN-bus based systems
The use of coil-overs with custom springs makes modifying the suspension so much easier than trying to put stock springs from a different car on the Civic struts. It costs a bit more, but allows for variances between Civic models and battery choices.
Picking a standard group-31 size of AGM battery makes the kit flexible and upgradeable

Improvements for the Kit

As with many engineering projects, documentation is rather sparse at this point. I think I captured quite a bit of stuff in pictures on the blog, but the official document is only about a third done and not reviewed.
The trickiest part of mounting the batteries was desigining the firewall rack. The tolerance between the motor adapter and the underside of the hood is very tight. Too low and you put lots of weight on the motor adapter. Too high and the hood won't close, even with denting in part of the support struts.
The vacuum pump is loud. period. I still haven't figured out a good valve pressure switch so that it maintains the right pressure at all times, but it's accepatble so far
For my car, I would have liked to get a white car to handle the heat in the summer better. Last summer, the dark blue car heated up quite a bit. Maybe I'll opt for a sunroof

Positive notes about Belktronix controller system:

I appreciate the holistic package that Belktronix provides with all the needed parts for a reasonable price
Documentation is excellent with lots of diagrams and troubleshooting hints
Support is excellent and prompt. You get to talk directly with the designer and don't have to escalate issues to get someone who knows how the system works
The vehicle Integrator module is great at telling you the status of the system through LEDs. The precharge sequence for the contactor works well.
I like the optical potbox. It mounts easily right under the accelerator pedal and will never suffer from mechanical degradation.
The controller seems very smooth and puts out good power. I haven't driven with something similar like a Curtis 1231C, but it accelerates smoothly
The battery shunt balancing system puts the shunt resistors off-board to prevent heat buildup near the battery. This also allows placement of the shunt resistors near a fan or other vent.
The external thermistor on the BatMon boards allows measuring battery temperature where it is most accurate. I've heard that putting it right on the battery terminal offers the least thermal resistance to the actuall internal battery temperature.
The Batmon boards offer individual low-voltage protection (LVP). The controller shuts down when the lowest battery reaches 10.8V instead of just monitoring the whole pack voltage. This prevents killing the lowest battery even though other batteries are okay

Improvements to the Belktronix system:

My biggest beef with the Belktronix system is the lack of programmability. It's an analog system where one needs to tweak resistor values to change any parameter. I can't argue that much since most other controllers are also analog in nature, but it would have been nice to change the acceleration curve or LVP cutoff voltage through a laptop.
I still need to figure out the LVP circuit. When the battery reaches 50% DOD, I lose all power and can barely creep along at 20mph. I have a bypass switch to get around this, but that disables any LVP protection I might have had.
The Batmon boards require quite a bit of wiring which makes the engine compartment look much like spaghetti. It also lends itself to reversed wires or shorts with the wrong terminal leading to blown BatMon boards or a blown Charge Detector. One company added two RJ-45 connectors to their battery boards and just used ethernet cable to wire everything up. No hassle with accidentally swapping or shorting wires and a much cleaner install.
I'm concerned that the Belktronix system taps off the main traction pack to power the contactor and the controller, where many others use the 12V accessory battery. This exacerbates pack imbalance and puts a higher load on a subset of the pack. I'm concerned this will cause the pack to degrade more quickly (or diverge more quickly).
The BatMon boards are just bare boards (with a protective coating). In the trunk, that's not a big issue, but in the front engine comparment, I've already had issues with fluids like the windshield washer fluid causing intermittent OVP faults. These definitely need to be enclosed.
One minor issue is that the controller system doesn't have an over-rev input on it. Bryan at Belktronix worked with me to make an interface that plugs into the back of the tach to create this function, but it's a bit messy. I realize this is problematic since it's hard to set the RPM limit without programmability. Many other systems don't have this feature either.

Overall, I think the controller is fine but the charging system needs some big improvements, especially the wiring spaghetti and bare BatMon boards.

Onward to more commuting!

Battery Imbalances

2009-02-04T09:12:00.000-08:00

I've been somewhat concerned with how imbalanced my pack has been lately. Given that the charging system has been blown for a few days, I'm not too surprised.

Here are some observations. The front two batteries behind the radiator grille are the lowest voltage in the pack. They tend to be the coldest because they get lots of air while I'm driving. They also get more drain then other batteries because they supply 24V to the controller and to the contactor. Furthermore, one of the front batteries is tied to the IsoBatMon unit. The IsoBatMon pulls no power when there is no LVP/OVP signal activity; however, when charging, it pulls 10mA when the OVP signal is on. I think the voltage drop across the zener diodes on that BatMon board is just a few tenths of a volt higher than the other BatMon boards (home fix job).

Thus, we have a perfect storm happening on the front-center battery that gets the highest load, and equalizes last due to a slightly different zener drop on the BatMon board. I think I'll swap boards with another battery to see if that lets the green light come on earlier.

In the end, the pack imbalance isn't horrible. If I take no-load voltage measurements on the batteries after they sit for an hour, the voltage difference is less than 150mV, so maybe my expectations are too high for what kind of balancing to expect.

Anyway, I'm just sharing these thoughts so they don't get lost in time. Cheers.

Aligning Suspension and Fixing Charging System

2009-02-03T18:48:00.000-08:00

Last Friday, I took the Civic into the suspension shop to replace the passenger-side axle (CV joint boot was broken), replace a brake line (those are important) and get a full alignment. The mechanic just couldn't get over how he could come to a full stop and not stall the motor without pushing in the clutch. The electrical specialist mechanic up the street took my card and vowed to come to the next OEVA meeting. I'm really glad I had the over-rev protection on the motor via the tach shift-light output. The mechanic revved the motor quite a few times while trying to shift like a gasoline car.

With the Charge Detector unit not working, I've been using my timer-on-a-cord to charge the batteries at night. For the past few days, I've been trying to figure out why the charge detector blew up. Many folks would have just sent it back, but with my EE skills and stubbornness, I chose to figure out the problem myself.

After taking a few days to study the circuit, I found a few blown components. I replaced the blown components and tweaked some resistor values and we'll give it another try with a full charge cycle tonight.

I'm not going to post any details of the circuit here for two reasons. First, Belktronix is moving to the Gen2 version of the charging system which doesn't use a charge controller and, second and more importantly, it's a proprietary design and I don't want to cause any ill will with Belktronix. I suppose I voided my warranty anyway by tinkering with it, so I'd better live with my decision.

The first two days of commuting this week went well. The outside temperature is warming up a bit (we're above 50 degrees F now) and the batteries are getting broken in, albeit somewhat jarringly.

Let's hope the rest of the week goes well...

My First Week of Commuting

2009-01-30T07:47:00.000-08:00

This has definitely been an interesting week. With the front suspension coil-overs installed, I felt much more confident in driving the car around without bottoming out. The link-10 is pretty good at measuring state-of-charge with Peukert compensation, so I felt good about knowing how much juice I had left.

I commuted to work three days this week (Monday, Tuesday and Thursday). It's 17 miles one-way with charging at work. I lose about 40% of my battery charge (DOD) in one direction which is what I was hoping for. Warmer weather might make this even better.

Things seemed to go fine on Monday. I left the charger on float-mode to make sure I didn't cook the batteries.

Tuesday was interesting. I woke up and found that the 1 amp fuse had blown on the 7watt DC-DC converter for the link-10. I replaced the fuse and the system worked again. Must be a glitch. I had some errands to run after work and the link-10 showed that I had 55% battery remaining when I started the errands, so I thought I was okay.

Around 48% remaining, the LVP protection on the Belktronix system kicked in and the car slowed to a crawl of 15-20 mph. I did what many EVers do: I pulled over, waited 15 minutes and then drove the remaining mile home. After waiting the 15 minutes, the car felt a bit better, but after 1/2 mile, it slowed to a crawl again, so I put on my hazard lights and got home. Trying to signal to change lanes with your hazards on is interesting.

I let the battery sit for 1/2 hour and measured the standing voltage on all the batteries. All showed 50% charge remaining except for one (tied to the IsoBatMon) showing %45 remaining. I'm guessing this one battery tripped the LVP (low-voltage-protection) signal and slowed the car down. To more quickly balance the pack, I put a 12V charger on the low battery at 30A for 25 minutes and then charged the car. I didn't want to get stuck like this again, so I installed an override switch for the LVP circuit going to the main controller.

Here's the override switch (top center). It's attached between the IsoBatMon unit and the motor controller. This enables me to see the LVP indicator on the dash if I need to put the system into override mode. Hopefully, I'll only have to use this for limping home.

Tuesday evening, I also started swapping out the rear suspension and found the chewed up strut (see previous post), so Wednesday, I commuted with the 914 EV and went out to purchase the new strut. Wednesday evening I finished the installation and made sure the Civic was charged for the Thursday commute after going for a run ride with my friend Andrew.

Thursday morning, I noticed that the 1A fuse for the Link-10 DC-DC was blown again. I replaced with a 2A fuse. I also noticed that the car was filled with a burning smell. I didn't figure out what this was until I was on my commute to work. It was the smell of overheated resistors, specifically the bypass shunt resistors for the batteries.

After arriving at work, I plugged in, knowing that the charger was in float mode and went to work. I drove home without a problem, did some errands (and opportunity charged with an extension cord to prevent the LVP "crawling along" problem) and went home.

This morning (Friday), I noticed the burning smell again and did some closer inspection under the hood. It turns out that the charge detector malfuntioned again (perhaps by the 30A battery charger?) and I've been dumping 8 amps of current into the batteries, even when full (argh!). All the bypass resistors had become discolored from over-heating.

I'm taking the Civic to the line-up shop this morning to fix the right-side CV joint (i.e. replace the axle) and do an alignment. I'll ponder what to do next at the shop...

Ugh.

Rear Coil-Overs

2009-01-30T07:37:00.000-08:00

To finish up the suspension, I installed the rear coil-overs. The procedure is much the same as the front coil-overs.

When the guys at Les Schwab swapped out the rear springs for the cut-down front ones awhile back (see this post), it looks like they chewed up the shock end pretty bad. I had to go to Auto-Adventure and buy a used shock. The whole assembly was only $30 and they have tons of used Honda and Subaru parts.

After following a similar procedure to the front coil-overs, the rear ones were in. For the rear height adjustment, I left six threads *above* the top edge of the gold ring instead of six threads below. The car is still sitting about 1/2" high, so I'll probably lower it a bit later.

Next up: reports for the first week of commuting.

Installing the Front Coil-Over Suspension

2009-01-25T14:27:00.001-08:00

Here's the process I used to remove the existing Civic springs and install the front coil-overs.

The first step is to jack up the front of the car and put it on jack-stands for stability.

Since I don't have a spring compressor, I'm going to use the entire car as my spring compressor instead. I rolled a floor jack under the swing arm and raised it until the car just came off the jack stand.

I then used an allen-socket wrench and a 14mm box wrench to loosen and remove the nut at the top of the shock strut. The allen-socket wrench prevents the strut from spinning while I loosen the lock nut.

This is the top of the strut with the nut and underlying washer removed.

I can now slooooowly lower the floor jack to release the tension in the spring. Even with all the tension released, there's still a bit of the strut top sticking out, as shown here.

Now to remove the bottom of the strut. The first step is to remove the two bolts holding on the brake line. After pushing the brake line aside, I put the bolts back in the nuts to prevent losing them.

Here I'm using a ratcheted socket wrench to loosen the top of the suspension fork.

I also had to completely remove the bolt at the bottom of the suspension fork. Once the nut is off this bolt, you might have to "finesse" it out with a hammer. I had to use a smaller bolt and hammer to slowly push it out. Sometimes you can just twist it with a socket wrench and the threads on the end of the bolt will force it out.

Okay, I removed the strut assembly and, in the process, released the coil spring pressure without a spring compressor.

If you remove the spring and slide off the strut cover, you can see the bump-stop (orange) attached to the strut.

The coil-over instructions say to remove the bottom half of the bump-stop. This seems to be made of a light rubber, so I was able to cut off the bottom half with a sharp utility knife.

The instructions also say to remove all but the top 1 1/2 inches of the strut cover. Here is the strut cover with the top 1 1/2" inches cut off. I used a file to remove the sharp edges.

After washing all the mud off the suspension parts, I'm now ready to put things together. The kit comes with a rubber sleeve to protect the inside of the coil-over thread cylinders.

With the rubber sleeve on, I now can slide on the coil-over threads.

Next is to slide on the custom spring that should handle the extra 400 pounds from the batteries. While this picture doesn't show it, it's best to rotate the gold ring so that there are 5-6 threads showing to the left of it before moving on. The assembly in this picture is at its lowest setting and needs to be raised to give a good ride height.

Next comes the large black "top hat" and the original washer that was above the strut cover.

Next comes the rubber flexible mount that sat on top of the washer. This picture should have the large black "top hat" in it, but doesn't (I had to try this a few times).

Now comes the upper spring perch that bolts to the chassis.

And finally the perch washer and lock-nut. If you rotated the gold ring to expose six threads, you'll have to press down somewhat hard on this perch to get the lock nut on. Ideally, you'd be able to adjust the assembly later, but it's easier to put the spring under slight compression now with the proper height dialed in.

Here's the finished assembly. As I mentioned before, you should really have about six threads showing to the left of the gold ring so that you can start with a good ride height. This picture was one of my first tries before learning about the proper height setting.

Install the assembly back in the car, following the directions in the Helms manual. Don't forget to put a floor jack under the swing arm and put the whole assembly at its normal height before tightening the suspension fork bolts. This will prevent the rubber fittings in the suspension from getting torn when you put the wheels back on the ground.

The above diagrams show the driver side. Repeat for the passenger side.

After I finished this and made sure there were six threads exposed below the gold ring, the front of the car sat at its original ride height of 24.5" from the ground to the fender. With this height, the car seems much less likely to bottom out when hitting speed bumps. There's plenty of adjustment room on the coil-overs to lower my ride in the future, if I so desire.

Have a great weekend,
Tim

Frustrations with Springs

2009-01-25T14:19:00.000-08:00

Okay, I admit it. I'm an obsessed control freak. That said, let's move on...

The drooping front suspension on the Civic is really getting me down (no pun intended) and I'm getting anxious with the coil-over kit sitting in my living room. So, I spent an hour and a half watching you-tube videos last night to see if I could install the coil-overs myself.

My biggest frustration is that I can't find a spring compressor that will work with the springs on the Civic. The space between the coils is just too small to fit a standard spring compressor in.

Remember this beast from several months ago? The hooks are too thick to fit between the coils, so it's been sitting in my garage.

I even ran out to Sears and spent $54 on a smaller pair of compressors. These are still too thick, so I returned them for a (fortunately) full refund.

In the end, I'm going to take a calculated risk and end up possibly damaging a bunch of stuff. Sounds like fun, huh? In short, I'm going to remove the springs and install the coil-overs without a spring compressor.

Here goes...

Over-Rev Protection, MTF and Labelling

2009-01-24T14:45:00.001-08:00

Today involved a bunch of miscellaneous items.

Bryan at Belktronix sent me a little circuit that plugs into the back of the tachometer that triggers the LVP protection and shuts down the controller when the shift light goes on. I basically routed a two-conductor cable through the grommet next to the throttle cable (where the cruise control cable would go) and connected the system.

This picture is crummy because it's difficult to see active LEDs when the flash goes off. I had to wedge the camera between the headrest and the seat to hold it steady enough for a flash-free photo. In short, you can see the bright red LED on the tachometer on, which is also activating the LVP circuit and turning on the battery idiot light on the dashboard (just above the "H" on the steering wheel).

After driving around a bit, I realized that I never really got over 4000 RPM, so I set the shift point at 4000 RPM, put the car in neutral and slowly pressed the accelerator. Surprise, surprise, the shift indicator came on at 4000 RPM, the LVP circuit went active and the controller shut down, preventing an over-rev condition. I pushed the circuit a bit more by pressing down a bit harder on the accelerator from zero RPM and it jumped up to about 4800 RPM before shutting down.

If you choose to implement this circuit in your own vehicle, make sure you set the brightness on the tach for the LED for its brightest setting. You'll have to set this brightness with the headlights on AND off since the tachometer saves two different brightness settings. If you choose a lower brightness, the LEDs gets pulsed and the controller won't fully shut off.

Thanks to Bryan for providing this circuit. I guess I have to fork over some $$$ to him now :)

As part of tying up loose ends, I also drove about 15 1/2 miles round trip to the Honda dealer to pick up two quarts of special manual transmission fluid (MTF). Honda recommends 10W-30 motor oil (which is in there now) or this MTF, which is much thinner. Since I have an electric vehicle, I'd like to remove as much friction as possible in the transmission.

This is the first drive that I took with the Link-10 E-meter hooked up. I appreciated the amp readings and the percentage of battery left over. It took me down to 45% depth-of-discharge to go 15 1/2 miles, so I'm guessing the full range of the car is really 30 miles or so. This will be fine for my 17 mile commute to work, one-way.

Since I'll probaby be showing off this car at a few electric vehicle shows, I wanted to label all the major components to help people understand what the parts are. I still have to mount all the BatMon boards inside plastic boxes, but I have to figure out a heatsink strategy first.

I feel much better now that the tach, over-rev, and link-10 E-meter are installed. This will give me more confidence is knowing how far I can go and how hard I can push the motor before shifting.

Cheers,
Tim

Suspension Toys

2009-01-23T20:20:00.000-08:00

Since I've been having difficulty finding springs that actually fit the car and handle the extra battery weight, I broke down and called Ground Control to see what they had to offer. They were very responsive and their technician recommended a coil-over set with custom springs for the project.

Delivery was remarkably fast. I ordered these Tuesday and they arrived today. The two thicker springs on the left are for the rear and the two on the right are for the front suspension. Ground Control offered to replace the springs for free if they didn't allow for a proper ride adjustment and I didn't drive on them.

Here are the installation diagrams that came with the kit.

Just so others can see the spring numbers they sent me, here's a copy of the invoice. A full suspension set for $350 isn't too bad, although it just eeks over my $10,000 goal for parts cost.

I'll be calling around to see who can install this set. My friendly local EV group (www.oeva.org) suggested a place about ten blocks down the street. They open again on Monday, so we'll see how it goes.

I still have to paint three metal pieces with POR-15 to prevent them from rusting, but the temperatures around here are still in the 30s (yes, I know that's balmy for some of you). POR-15 doesn't really stick until it gets above 50 and I don't want to use that stuff inside where I might get woozy from the fumes.

Finishing the Guages, Link-10

2009-01-23T20:02:00.001-08:00

I worked all day to get the tach sensor fixed and the link-1o installed.

Here's my solution to fixing the tach sensor. I'm using a stainless steel bolt to hold it in (which is just barely magnetic). I'm also using a salvaged plastic gear as a non-magnetic spacer to put the spinning magnet disk inside the sensor housing.

At first the gear was too thick and the head of the bolt rubbed against the inside of the sensor housing. After filing the gear down to 1/4 inch, it seems to work well, even under acceleration.

In hooking up the system, I cheated a bit and pulled the positive 144V tap needed for the Belktronix system off of the other side of the main circuit breaker. This saved a bit of wiring, but (as always) ended up biting me when I wired up the Link-10. This is a picture of the Airpax circuit breaker under the car. The 144V tap is coming from the rear battery pack is on the left post. I added a 16 gauge wire to this post and ran it into the engine compartment to attach to the Belktronix system and the link-10 connections. This allows the breaker to blow and also let me disable the system without losing power to the link-10.

Here's installing the 500 amp shunt for the link-1o meter. I have just a little space left on the driver side chassis. Just above the shunt are two silver-looking indentations aligned vertically. Those are the marks I made with a 3/16" drill through the mounting holes in the shunt. I used those to drill some holes and insert two 8-32 threaded rivnuts.

Here's the shunt mounted into place with the 8-32 bolts in the installed rivnuts.

When I had the car running before this, I simply had a negative battery cable from the Belktronix controller running directly to the negative terminal on the battery. With the shunt, I now break this path and use two cables, with the shunt in between. While your mileage may vary, I cut welding cable 9 1/2" long for the battery post to the shunt and 13 1/2" long from the shunt to the controller negative terminal.

Just under the 2/0 cable bolted to the shunt, you'll see a piece of four-twisted-pair cat5 cable. The link-10 requires a twisted pair of wires from the shunt to the display to reduce noise. Since there are only three other connections going to the display besides the one twisted pair, I decided to combine the other three twisted pairs into single wires to carry more current. The combined brown pair goes to link-10 pin 1 (negative terminal). The green twisted pair takes the differential signal from the shunt (link-10 pins 2,3). The blue combined blue pair goes to link-10 pin 4 (high voltage prescaler output) and the orange combined pair goes to pin 5 (7watt DC-DC output).

Here's everything wired up. The shunt is wired and I found some space for the Belktronix DC-DC and Link-10 prescaler beside the engine mount. Note the filler cap for the washer fluid. I'll have to be careful filling this since the washer fluid is somewhat conductive.

Yay, the link-10 works and tach above it as well. After reading the manual and setting some parameters, it seems to work fine. I used the following for my system:

charging end voltage: 172V
Peukert Constant: 1.11
amp-hour capacity: 100

I still have to configure the tach shift light to stop the motor from over-revving. I'll get to that tomorrow.

Debugging the Tachometer Signal

2009-01-20T21:28:00.001-08:00

I spent this evening, trying to figure out why the tachometer was flat-lining under acceleration. After talking with some EMI suppression engineers at work, they suggested covering the sensor with a steel shield to prevent magnetic fields from interacting with the sensor.

So, I headed out to the grocery store and got a nice steel can of organic tomato soup. After dinner, I washed out the can and cut the bottom two inches off with some tin-snips. After covering the sensor with this and revving up the motor, I still had the same problem. Rats!

The next experiment was to purchase a piece of 24 gauge steel plate from Parkrose Hardware and cover the face of the motor behind the sensor to see if I could prevent magnetic fields from interfering. I drilled a 1" hole to fit over the spinning magnetic disk and drilled two holes to match the mounting holes.

Result: After installing this under the plastic spacer ring, the tachometer failed to work at all. Rats again!

However, this did provide a clue to what was going on. The steel plate (along with some wiggle room) added about 1/16" spacing to the sensor. After taking some more measurements, I found that the spinning disk was only just inside the bottom edge of the Zolox sensor.

As a third experiment, I added 1/4" of spacer washers under the spinning magnetic disk to push it deeper inside the sensor housing. This actually worked fine, at least for mild acceleration. The spacer was loosely added, so I'll make something more permanent tomorrow after I get some decent spacer hardware.

In short, make sure the spinning magnetic disk is deep inside the Zolox sensor housing to make it work.

Good Night,
Tim

Making a Charging Timer

2009-01-18T16:12:00.001-08:00

I wanted to make a timer so that I could charge the car for a specific amount of time to prevent over-charging the AGM batteries with the Belktronix charger. The only timer I could easily find that would charge for several hours was a wall-socket mount like the one shown above. I found a weatherproof box with weatherproof cover and mounted the timer in the box. There were also special cord protectors that screwed into the holes in the box. I simply cut a 25 foot 14-gauge extension cord in the middle and wired in this contraption to limit the time on my charges.

Mounting the Link-10 E-meter

2009-01-18T16:06:00.000-08:00

I decided to start mounting the Link-10 Battery Monitor (E-meter) this weekend. As many of you know the Link-10 is very deep and doesn't fit too well in typical pillar pod holes.

To solve this problem, I purchased a piece of 2" (inside-diameter) ABS plastic tube from Home Depot for $3. This is very common stuff and should be in the plumbing tube section.

I basically cut a 1 1/2" piece of this tubing and filed the end to make it smooth and flat. I then used black industrial plastic adhesive to glue it to the pillar pod hole as shown here.

After the adhesive dried, I was able to slide the link-10 in quite easily and use a tie-wrap to hold it in place. I have to rewire some of the engine compartment and add the shunt before I can wire this up.

Real World Driving Tests

2009-01-17T07:12:00.001-08:00

I had a chance to take the Civic out for about 25 miles yesterday (two charges) and see how it handles in traffic and on the freeway. Here are some first impressions.

The potbox, being directly under the accelerator pedal, is very sensitive, especially at slow speeds. Since the Warp9 is rather powerful, trying slow moves in reverse gear are tricky. This can be problematic for parallel parking where a sudden lurch might send you into another car. There's a positive feedback loop where if you press just a little too hard while in reverse, the car lurches backward, which makes your body/leg move towards the front of the car and press the accelerator even more, causing an even bigger lurch. Be careful in lower gears!

Given the power the Warp9 and sensitivity of the potbox, starting in second gear seems to be just fine, even on hills. Even starting in third gear works well if you don't need jackrabbit starts at stoplights. Higher gears take the jolt out of moving the car so you get much smoother, albeit a bit slower acceleration. I plan on using third in stop-and-go traffic due to its smoothness.

If I didn't pay attention, very light acceleration in second gear gave me oscillations in car movement. This again was caused by negative feedback between my body/leg mass and the accleration of the motor. If I'm not careful in second gear, light acceleration will cause the car to lurch forward, pulling my body/leg towards the back of the car, releasing the pressure on the acclerator and slowing the car down. This slowing returns my body/leg to a neutral position where I'm accelerating again and... well, you get the point. This is only my first major day driving so I'm sure I'll get trained to the dynamics of the car.

As with many DC motor powered cars, accelerating from zero to 30 mph is great and getting up to 60mph is a bit slower. I can get on the freeway no problem, but it does take a few extra seconds over the original stock Civic. With the Belktronix system, the batteries tend to sag to their low-cutoff point of 10.8V under heavy acceleration. I'm tempted to add an "emergency power" momentary-push button that disconnects the LVP protection to the controller in case I need an extra boost (Think "Turbo" button in Knight Rider) to save my ass when I don't care about drooping down the batteries lower than 10.8V. I'm guessing that Bryan at Belktronix is cringing at this statement, but, hey, they're my batteries and can kill them if I want to.

I'm very thankful that I chose to keep the clutch for this implementation. Shifting is a breeze, both up and down without any delays whatsoever. It just feels so much like a regular ICE car but without the noise and pollution.

Overall, I've been pretty happy and nothing has blown up yet, so we'll see how things go as I break in the batteries and start commuting.

Cheers,
Tim

Tachometer Problems and Insurance

2009-01-14T21:11:00.000-08:00

As with any project, things rarely go as you hope they do. The Zolox speed sensor, which has been used in countless EVs is flat-lining (i.e. being pulled down) whenever I accelerate, which gives me a tach RPM of (drum roll....) zero. The Zolox sensor works using a magnetic sensor that detects four small magnets in a spinning disk. It turns out that having a 9" DC motor that puts out large magnetic fields interferes with this (go figure).

After getting some advice from Bryan at Belktronix and some EMI suppression engineers from work, I plan to add some steel shielding around the Zolox sensor to break up the magnetic flux lines that may be interfering with the sensor. Stay tuned...

Since this vehicle is now road-worthy, I thought it might be a good idea to get it fully insured before I take too many long drives. Getting insurance for an EV conversion is somewhat tricky. There's a local insurance agent who promotes electric vehicles but was rather embarrassed when her underwriter refused to insure my vehicle because I wanted to use it as a daily driver. Apparently having an EV conversion that's just a weekend fun vehicle isn't a problem. I ended up going with Progressive auto insurance and was able to get what I wanted.

Installing the Tachometer

2009-01-14T20:47:00.000-08:00

Happy Belated New Year everyone! Things have been quiet on the blog recently as I've been taking a break for awhile.

Last week, I installed the tachometer in its pillar pod.

Here is the pillar pod next to the driver's side A-pillar that I pulled off. I originally marked a line (see left end) where the two-gauge pillar pod should rest. I marked where I could drill two holes to route wires through. The circle with the X through it would have been ideal for the tachometer, but...

...you can see the hole would have interfered with the metal clip on the bottom of the A-pillar, so I moved it an inch higher.

The instructions call for drilling four 3/16" holes in both the pillar pod and A-pillar to install bolts through. I clamped the two together (without the tach installed) so that it wouldn't shift around.

Here are the two parts ready to install with the 1" holes drilled for the wiring.

The tachometer has six wires coming out of it. Two of them attach to the ground and +12V for the face lighting. To save wiring and utilize the existing wire harness, I simply spliced the face lighting wires into the ground and pointer-light wires from the main connector. To keep things a bit cleaner, I zip-tied the whole thing together.

Okay, now for the hard part. The tach wiring harness simply four dangling wires attached to a connector. I placed electrical tape every 9" along the harness to make a single thick snake. I then taped the ends together and fished it down where the bottom of the A-pillar was to underneath the dashboard.

I received a special circuit from Bryan at Belktronix that plugs into the shift-light output on the tach. In order to thread this back up to where the A-pillar is, I taped it to the cable that I threaded downward and then pulled everything through to fish it upward.

Here is the tach wiring harness with white connector and the 1/8" stereo plug that I fished up towards the base of the A-pillar.

Here are those same two cables, now plugged into the back of the tachometer, which is installed in the two-guage pillar pod.

With the tachometer/shift-light wires routed underneath the dash, I now had to get the Zolox speed sensor signals from the engine compartment to underneath the dash too. Here you can see the Zolox speed sensor wire (finger touching it at left edge of picture) going through the rubber harness grommet. I just punched a small hole with an icepick and fished it in.

Here's my wiring scheme to connect the tach to the Zolox sensor and the car wiring.

Red from the tach goes to the keyswitched +12V and the red wire that powers the Zolox
White from the tach goes to the headlight switched terminal in the car to power the tach pointer and face lighting
Black from the tach goes to the car ground and the black ground out to the Zolox sensor
Yellow from the tach goes to the white signal line from the Zolox which also ties to a 2.2K pullup resistor through to the +12V red wire above

If you enlarge the picture, you can see the small 2.2K resistor between the red and white wires just to the right of the fast-on connectors.

Since my Civic didn't have any options installed, getting access to the keyswitched +12V and headlight switch power was fairly easy. There are some fast-on terminals on the fuse block just above the fuses. The second from the right (white wire) gets +12V when the headlights are on. The third from the right gets +12V when you turn on the keyswitch (but goes off when you turn the key to "start").

With things installed, I revved the motor and measured the pulses coming from the Zolox (4 pulses per revolution) with an oscilloscope. The picture is bad because I couldn't use the flash on my digital camera and the camera sampled multiple times. I verified that I had programmed the tachometer correctly because I was able to get 6000 pulses per minute and have the tach register 1500 RPM.

Add the Splash Guard

2008-12-29T21:29:00.000-08:00

I'd like to get the car off the jack-stands and back into a position where I can drive it while still adding things like the guages. After installing the speed sensor, the last thing needed under the car is the splash guard to protect water and grit from getting into the Warp9.

After playing around a bit, I found that a piece of ABS plastic 15" x 18" and 3/16" thick will probably work. I've used a 9/32" drill bit to drill four holes in the plastic so I can tie-wrap it to the factory splash guard and the transmission.

Here's the plastic tie-wrapped to the original splash guard. For the lower-left tie-wrap in the picture, I had to drill through both the 3/16" plastic and the factory splash guard to get the tie-wrap through. The remaining hole in the upper right will be to attach that corner to the bottom of the transmission. The tranny mount hole is 1.5" in from the right edge.

Here's the splash guard in place. There was a spare bolt hole under the adapter plate with no bolt in it, so I found a bolt that fit and used that to attach the tie-wrap for that corner. Although the bolt sticks out, it's actually rather tight because it's bottomed out in the transmission case, so I don't expect any problems. I could have probably used a beefier tie-wrap, but it works for now.

Here's the underside of the installed splash guard. It completely covers the bottom of the Warp9 but gives it about 1" of clearance to breathe for cooling. This picture was taken from under the car looking towards the drivers side wheel hub. The front of the car is to the right.

The next task will involve hooking up the tachometer and the Link-10, which will be tricky since it involves a lot of under-dash work.

Good Night.

Mounting the Zolox Sensor

2008-12-29T21:18:00.000-08:00

After futzing around awhile, I was able to get the spacer ring for the Zolox tachometer sensor to line up.

Here's the bottom of the mounting ring. The screws that came with the mounting kit stripped out the plastic, so I sunk some depressions in the backside of the ring where the bolt holes were and put in 8-32 x 1" bolts from the backside.

Notice that the large holes in the upper left and lower right are somewhat warped. I had to use a drill to hone out the holes in the proper direction so that the ring was actually centered on the motor tailshaft.

Here's the topside of the mounting ring with the Zolox sensor bolted to it with nylock nuts. There's actually a space between the black flange on the sensor and the mounting ring, so don't tighten these bolts too tight. The grey mount on the lower right holes the wiring so it doesn't flop around.

I drilled a hole in the center of the tailshaft and then used a 1/4" bolt to align the magnetic disk with the hole. I didn't have a tap to put threads in the center of the shaft, so I just epoxied the whole thing on, using the bolt to keep the magnetic disk centered.

Here's the sensor assembly bolted onto the motor over the tailshaft. The bolt holes had a little play to them, so I had to make sure thing were lined up. I put the Civic in third gear and blocked one wheel so that I could rotate the hub to spin the motor shaft. After spinning the motor shaft and verifying that the magnetic disk didn't rub up against the inside of the speed sensor, I tightened down the bolts.

The sensor comes with a shielded cable with three wires. Red is +12V, black is ground and white is an active pulldown. My test setup shown here includes a small 12V battery on the right (from an old UPS) and my multimeter. I added a 2.5K resistor to pull the white wire up to 12V when the sensor wasn't actively pulling down. Surprise! It actually works and generates high and low voltages as the motor shaft spins. The real acid test will be to see if it triggers the SpeedHut tachometer properly.

Frustrations with Zolox sensor mount

2008-12-29T12:16:00.000-08:00

I tried installing the Zolox sensor mounting ring for the Warp9 motor from EVsource today. It looks like the holes on the mounting ring don't line up properly. The holes for the Warp9 casing don't match, so I had to drill them a bit larger so the bolts would go in.

Here I've placed the spinning magnet onto the end of the tailshaft with a short 1/4 bolt to properly center it. If you look closely, the spacing is off so that the shaft isn't properly centered in the mounting ring. It looks like the fabricator got the holes offset. This position is critical because the spinning magnet only clears the inside of the sensor by about 2 mm on all sides which is really close.

Furthermore, I tried using the supplied screws to attach the Zolox sensor and they immediately stripped out the plastic. I'm frustrated that a mounting ring that should just work wasn't really thought out that well.

With stripped out screw holes and a non-centered shaft, this spacer ring really needs some work. I intend to countersink some depressions on the bottom of the screw holes to allow for a true bolt to go through the ring with a nut. This shouldn't strip out and allow for better mounting. As far as getting centered, I'm not too sure the best way to do this. I'll either have to re-drill the holes in a different place or drill the existing ones larger and clamp the ring down hard in the proper position.

Ugh. Happy Monday.

Christmas Presents

2008-12-29T12:10:00.000-08:00

Santa was good to me this year. I received a Link-10 battery monitor from my parents. I don't think they understand what it does and why it costs so much, but okay, they got it for me anyway. The items on the right came from Belktronix. The wires on the upper left are the Link-10 voltage prescaler. The module on the upper right is the DC-DC to supply an isolated 12V to the link-10. The grey cable on the lower left is the tachometer interface which activates the LVP motor shutdown when the tach shift light turns on. The pink bag on the lower right is the fixed BatMon board with a zener diode.

I have a week left of vacation to try and get this stuff working. We'll see how it goes.

Happy New Year to all.

Tach Mount, Splash Guard and POR-15

2008-12-19T18:27:00.000-08:00

It's still pretty cold in the garage, but I motivated myself to get out to TAP plastics (10 blocks away) and pick up some ABS plastic for the improved splash guard.

Here's the 3/16" thick piece of ABS lying on top of the existing splash guard. I got a piece 36" x 18" which is way too big, but I didn't know what would be needed. In the final directions, I'll probably list a smaller piece to acquire. This one cost me $22.25. I'm going to figure out how to cover under the motor vents to prevent grit from getting in there while still allowing adequate airflow for cooling.

Since I cut off the tailshaft on the Warp9, the Warp9 mounting ring for the Zolox tach sensor was too thick. I took that to TAP plastics as well and had them cut it to the proper thickness while keeping all the proper mounting holes for the sensor. The original donut was 1 1/2" thick. After cutting the tailshaft, I had 3/4" left over. If I cut the mounting donut down to 1/2" thick, it would leave 1/4" plus the spinning magnet (another 1/4") to protrude inside the tach sensor sleeve.

I wanted to make sure the spinning magnet sat in the center of the tailshaft. With the full tail shaft, there would be a 1/4" threaded hole to mount it into. Without the hole, I chose to drill a 1/4" hole in the center of the shaft about 3/8" deep to match the 1/4" hole on the spinning magnet. This will allow a short 1/4" bolt to keep the spinning magnet centered while I epoxy it on. Ideally I would have used a tap tap to make a threaded hole, but I didn't have one and this was quick and easy. Note that I used masking tape to cover up the tail bearing to prevent metal shavings from getting into the motor.

Since the mounting hardware that came with the donut above was meant for a 1 1/2" thick donut, I'll get the proper hardware tomorrow to install the donut and Zolox sensor.

Another nice surprise! The POR-15 starter kit arrived today as well. There were three battery hold-down pieces I didn't finish before sending all the metal pieces off for powder-coating, so I'll have to coat them myself. POR-15 is really tough stuff and this $20 starter kit will have everything I need. (no, this isn't an ad for POR-15)

For those who are curious, the starter kit contains metal cleaner, surface preparer, the POR-15 paint itself, rubber gloves and application brushes. I'll have to find a slightly warmer day to apply this stuff since I don't want to inhale fumes in my closed garage.

I'll be going snow-shoeing tomorrow, so maybe I'll get to installing the sensor on Sunday.

Tachometer is Here!

2008-12-18T19:10:00.000-08:00

This is a cool day(And not just because it's freezing outside). The package with the custom tachometer from SpeedHut arrived.

Although I received the 2-hole pillar pod last Friday, I wanted to show it here since I ordered both items from Speedhut. The wiring harness is nice and long. The small module in the lower left of the photo is the dash light interface which allows a variable dash light brightness to control the tach brightness as well.

This is just too awesome for words. I hooked the tach up to a small 12V battery to light up the dial. I'm psyched that I got the "Civic EV" lettering for free.

On the backside of the tach is what looks like a standard 1/8" stereo audio jack to drive an optional shift light LED. This is what I'm going to drive the LVP signals with to disable the motor controller PWM if the RPMs get too high. Bryan from Belktronix is working on an interface now (tentatively for $10-15) that will tie this output into his controller system as a rev-limiter.

Progress is slow these days due to the cold weather. The garage is freezing and I'm not motivated to work too much with frozen fingers. My employer is forcing everyone to take off the next two weeks to make the financials look better, so I'll have time to wire up the tach and possibly finish the splash guard under the car. Since the roads have been covered with ice, I'm leery about taking the car out and sliding it into a ditch.

A small can of POR-15 should be arriving tomorrow that I can paint the remaining battery hold-downs with and there's one Batmon board left with a bad zener diode on it that's back at Belktronix for repairs.

Charging parts back and more miles

2008-12-14T12:47:00.000-08:00

I received the fixed charger parts back from Belktronix on Friday and installed them with no problems. After going through a full charge cycle, I did find another Batmon board that was activating the shunt resistor at 13.5 volts instead of the expected 14.6 volts. I'll look into that early this week or send it back for repairs.

After fixing up the charging system, I took a quick test drive with my friend Jonathan for about 7 miles and the car behaved well. The suspension is still a bit off (rear is 2" high while the front is 1" low), so I'll look into fixing that.

Stuff still to do:

Fix the zener diode on the failing Batmon board
Fix the suspension ride heights
Figure out how to encase the BatMon boards while allowing FET cooling
Paint remaining hold-downs (not powdercoated) with POR-15
Install Link-10 system after Christmas
Install tachometer with shift light going back to controller for over-RPM protection

Last evening, I drove the Civic to a party at FreeGeek, a local computer recycler and showed off the car. There's a significant hill between FreeGeek and my house; the Civic did quite well starting on the hill. This is a far cry from the white-knuckle hill-starts I've been living with in the 914. What a relief.

We just got about three inches of snow on the ground today, so I don't think I'll be joyriding or testing the full acceleration of the Civic for fear of sliding off the road. I just updated the EVAlbum entry with some mileage so I'm officially out of the "under construction" stage.

Plastic Boxes and Speed Sensor

2008-12-11T17:57:00.000-08:00

I got some fun stuff today. The plastic boxes for the BatMons and the Zolox speed sensor with Warp9 mounting hardware came in.

Here's a pile of 2x2" plastic boxes 1/2" high that fit the BatMon boards quite well. If I cut off one side, I should have at least some protection from splash and other grit that enters the engine compartment.

Here's the Zolox speed sensor from EVSource. I don't know if it will work correctly with the SpeedHut tachometer that's coming, but I hope so. It took me awhile to figure out what the wires were. Red is +12V, Black is GND and Green is an active pulldown (Otmar uses a 2.6K pullup) every time a magnet (4 per revolution) in the small wheel passes the sensor.

Here's the spacer ring that allows easy connection of the Zolox sensor to the tailshaft of the Warp9 motor, also from EVSource. Since I cut my tailshaft off and there's very little clearance, I might not use this, or slice it thinner. With the cut tailshaft, I also lost the threaded hole in the middle of the shaft. I'm thinking about epoxying on the magnetic wheel instead.

Assembling a Price List

2008-12-08T22:18:00.000-08:00

I always wondered how much this kit really cost me, aside from tools, so I assembled a total parts price list and uploaded it to the Civic-EV Google Group here:

http://groups.google.com/group/civic-ev-kit/web/SystemPricelist.xls

I'm a bit surprised I came out below $10K (barely).
For those of you who have done conversions, please check my spreadsheet and let me know what I missed. One of the high-wants for the kit was that it would cost < $10,000 and I might have actually done it.

Cheers,
Tim

A Different Tachometer

2008-12-08T20:38:00.000-08:00

After a suggestion I received from Bryan Belk (of Belktronix), I decided to go with a different tachometer than the cheap Shucks one:

http://www.speedhut.com/custom_gauge_description-gauge_type-Tachometer-auto_number-700.htm

This tach is only $96 and comes with a customizable face. I was even able to add the text "Civic EV" for free! The other cool thing is that it has an LED driver on the back for a particular shift point. This could easily be set and tied into the LVP (low-voltage-protection) circuit on the controller to prevent over-revving the motor. Initially, I was going to create a someone complex circuit that measured the spaces between tach sensor pulses and triggered the LVP circuit when they got too quick. This gauge takes care of that function and allows non-circuit designers with the open-source kit to have over-rev protection as well as a really cool tachometer that fits easily into the 2" pillar pod.

With all this stuff ordered, I'm just enjoying a little down time until things come it. Cheers.

Ordering Gauges

2008-12-08T06:57:00.000-08:00

While I wait for the charging components to get fixed, I did some research on gauges to monitor the state of the system. My goal is to use as much of the existing dashboard as possible and then add low-cost gauges in order to prevent any motor problems and detect faults.

The list I came up with:

Mount a Link-10 E-meter in a pillar pod to monitor current and state-of-charge
Mount a tachometer in a pillar pod to monitor RPM and use the sensor as an over-rev protection device
Make a circuit to drive the "low oil" light when the 12V car battery is less than 13V to detect DC-DC failures
Tie the "battery" light to the low-voltage signals on the Belktronix system to point out undervoltage on the main pack
Make a circuit to drive the "check engine" light when the motor overheat contacts open on the Warp9
Future Option: find a temperature sensor that attaches to the Warp9 that will drive the temperature gauge on the existing dashboard

To that end, I went ahead and ordered the following

I still have to find out the best pillar pod for these gauges since the Link-10 monitor is physically deep and will probably stick out quite a bit. I also have to design the schematics for the oil light and overtemp light.

In order to protect the BatMon boards from water splash (at least in the engine compartment), I ordered a bunch of 2x2" plastic boxes. I don't know if these will work since I don't know the heat dissipation requirements, but I'll give it a shot.

Have a great week everyone,
Tim

Cleaning up Loose Ends

2008-12-06T14:07:00.000-08:00

After working with Bryan from Belktronix yesterday, I found out that I had blown some components in the IsoBatMon, the Charge Detector and one of the BatMon boards. Those went off in the mail this morning back for repairs. I'll try the system again when the parts come back.

In the meantime, it looks like the speedomter is working again. I also purchased a new headlamp to fix a burned out right hi-beam. It turns out the problem wasn't the bulb but a *missing* fuse in the fusebox. I suspect the prior owner sacrificed the fuse to fix another circuit but didn't replace it. Oh well, I now have a spare bulb...

The Belktronix system calls for a 60A fuse between the DC-DC and the main battery. I utilized the existing alternator input for the DC-DC output and replaced the factory 80A fuse with 60A equivalent.

Theoretically, I could drive the vehicle now, but charging would get very tricky as I don't have a charge monitoring system. I'd have to watch the battery voltage like a hawk or risk hurting the batteries and shunt resistors.

There's still much work to do in the way of deciding which gauges I should use and writing open-source instructions. At this point, I'm a little burned out, so I'm going to take this weekend and just clean up the house (there are EV parts *everywhere*) and get my dining room table and kitchen back.

Many thanks to all the congrats and well-wishers out there who have supported me in this effort. I hope this open-source project proves fruitful, especially if gas prices go back up next year.

Cheers,
Tim

Wiring up and Testing Batmon Boards

2008-12-05T13:19:00.000-08:00

Okay, it's time to get your wiring spaghetti on. I spent part of last evening (after fixing the speedo) and all of this morning wiring up the Batmon boards. In the process I blew the OVP channel on the IsoBatMon unit.

Here I'm crimping yellow 3/8" ring terminals on all the blade fuse holders that will hold the 7.5A fuses. I tried to do as much as I could on a workbench instead of in the cramped quarters of the car.

Okay, I've finished wiring up the front set of batteries. If you look closely (click picture to zoom in), there are the two grey LVP/OVP cables on the right side of the picture. The two thinner red/black paired wires in the upper left of the photo are the LVP/OVP signals going to the two front batteries.

Here is the finished Batmon wiring in the rear trunk, showing the speaker wire going to the shunt resistors and the twisted, colored computer wires connecting the LVP/OVP signals between the boards.

I came up with this little device to test all the Batmon boards. It's basically a 3V supply with 2 AA batteries and spade terminals on the wires. The spade terminals are smaller and much thinner than your standard 1/4" fast-on terminals. This enables them to slide easily into the fuse socket without much entry or removal force.

How does it work? Instead of plugging in the fuse, you plug this 3V supply in to the fuse sockets in both directions. In one direction, it adds 3V to the 12V battery supply, making 15V which triggers the OVP circuit. In the other direction, it subtracts 3V from the 12V supply, making 9V which triggers the LVP circuit. With this, you can verify that both Batmon circuits are working AND you can check the red and green LEDs on the IsoBatMon board to make sure this board is properly talking to it.

Here's the 3V tester in action. I have the red(+) side plugged into the left side of the fuse holder which is tied to the +12V of the battery. The black(-) side is plugged into the right side of the fuse holder, giving the BatMon board 9V. It's hard to see due the camera flash, but the red LED on the BatMon board is lit up, showing that the circuit works. The red LED on the IsoBatMon board has also lit up, indicating a proper connection back to the main system.

While working in the trunk, I briefly touched one of the OVP signals to a battery terminal and fried the OVP side of the IsoBatMon. The BatMon board itself works, but when it's opto-isolator shorts out the master OVP pair running through the car, the green LED on the IsoBatMon fails to light.

Since the IsoBatMon is powered from a battery "low" in the pack (around 12V), touching the OVP signals (or LVP signals for that matter) to any battery terminal "high" in the pack (say, 96V) will send a high-voltage, high-current spike through the opto-isolator (and LED) on the IsoBatMon. Kerplooey!

I'm going to see if I can work with Bryan from Belktronix to fix this. In the meantime, I'm going to short the OVP signals coming OUT of the IsoBatMon together to force the charging system into low-current mode to prevent overheating any of the shunt resistors.

Onward!

Fixing the Speedometer, Removing ECU

2008-12-04T22:19:00.000-08:00

During the test drive, I noticed that the speedometer wasn't working. It had worked fine before I removed the engine. After researching the Helms manual, I needed to get at the speed-sensor on the transmission to figure out what was going wrong. Fortunately I hadn't yet wired up all the BatMon boards, so removing the firewall batteries to get at the sensor only took a few minutes.

Here's the firewall battery rack with two batteries removed to get at the speed sensor on the transmission. I'm pretty happy with how quickly I could remove the powder-coated hold-downs and remove the batteries.

Here's the non-functional speed-sensor. The debug procedure is to remove this and test the voltage at each of the three wires. It turns out I had a bad ground connection (black wire). The original ground came from a bolt on the engine which no longer exists. The black ground wire actually went up the wiring loom all the way to the engine harness connector, so I could fix it there.

Here's the fix for the problem: Find the all-black(no stripe) wire on the engine harness loom just in front of the driver and ground it to the chassis. This ground wire actually supplies the ground not only for the speed sensor but for the ECU. I used an automotive wire splice (pinkish connector) to splice in a piece of 16 gauge wire to a blue ring terminal on the chassis.

Speaking of the ECU. I guess it's pretty useless now, and I can tap into some of its wires to drive lights on the dash or sense other parts of the car. Since I don't want it drawing extra current (probably not much anyway), I decided to remove it. Here is the passenger side carpet pulled away so I could get at the ECU bolts.

Here's the ECU unbolted on the passenger side floor.

Just for yucks, I opened it up to see the inside. I'll probably sell this if there is a local buyer.

After checking a few other electrical items, I noticed that my 12V car battery was actually quite low (11.8 volts). I'm pretty sure it came this way, since the DC-DC converter appears to be working. I'm leaving it on a 13.6 volt float charge overnight (perhaps the weekend) to see if I can get it back to full.

Next up: wiring up all the BatMon boards (spaghetti, here we come!)

Buttoning up the Exterior

2008-12-03T18:29:00.000-08:00

Even though all the BatMon boards are not wired up, I was itching for a quick test drive. It was time for me to get the wheels on the car and take it for a short spin.

This is the picture of my front hallway closet. I had originally stored the tires from the Civic in the front hall, but my cats licked the brake dust off the inside, so I had to put them in the closet. They didn't fit that well and kept tumbling out every time I opened the door.

As you can see, they just don't fit that well...
The tire on the lower left is the spare tire for the 914. The batteries prevent me from carrying in the car.

Okay, here we are installing the tires back on the car.

I re-installed the splash guard under the front of the car, but found that the new front battery rack angle-iron interfered with it. Here are pictures of the chunks I cut out of the splash guard to get it to fit around the front rack.

With the wheels on, I used the floor jacks to lower the front end of the car onto the ground. What!?? There's fluid leaking out onto the floor! I realized that there was still coolant in the heater core inside the car that drained out when I lowered the front end. With the front lowered, I used the floor jacks to lower the rear end as well.

Here's the Civic with it's freshly applied "ELECTRIC" emblem on the back! It drove out of the garage quite well.

And here we are, ready for a short test drive. The front suspension is a bit lower than I'd like. There's only about four inches of clearance, but I'm sure it'll work.

At this point I took it for an EV-grin spin around the block. Videos are here.

Many thanks for all the people who have answered my questions and offered support during this project. There still a ways to go, but things are looking good.

Best wishes,
Tim

Routing the LVP/OVP Cables

2008-12-03T18:27:00.000-08:00

In addition to the thick, high-current battery cables, we need to route the OVP (over-voltage protection) and LVP (low-voltage protection) wires from the rear BatMon boards to the front BatMon boards. The instructions say to route these away from the high-current cables and away from each other to prevent noise.

I decided to route these through the rubber plug that the fuel tank wires go through. Here is the rear seat lifted up and the fuel tank cover removed. I've cut the fuel gauge wire and fuel pump power cable.

Here are the two shielded OVP/LVP cables routed through the rubber plug with the cover screwed back down. These cables run rearward under the seat backrest into the rear trunk where the batteries are.

Here's the same fuel tank lid, but under the car. This also shows a little of how I routed the high-current cable in the radiator hose along the brake lines to the holes in the sides of the rear trunk.

This shows how I routed the OVP/LVP cables along the underside of the car towards the fuel line brackets. I tucked these cables behind the brake lines and tie-wrapped them in to protect them from road grit.

This shows the OVP/LVP cables coming out of the brake line run at the front of the car and going up into the engine compartment.

I wanted to make sure these lines didn't interfere with any moving parts, like the steering column, so I tie-wrapped them to other non-moving cables to keep them out of the way. Later, I'll connect these to the BatMon boards in the front and rear to enable communication.

Wiring Things Up and Testing

2008-12-03T18:24:00.000-08:00

Much of my time was spent wiring up the controller, charger and integrator box from the Belktronix kit.

I had to unbolt the charger in order to get access to the fast-on connectors on the side of the main motor controller.

The Belktronix instructions come with a checklist of things to do before powering up the system. I had my handy Fluke meter out to find any problems.

Here's a top-down look at the vehicle integrator module all wired up. I've just turned on the ignition key and all the proper LEDs have lit in the integrator module.

Another sign of success is that the fan on the controller (near top of picture) is now spinning.

I wired the DC-DC converter right into the alternator input connection, again leveraging the existing main fuse in the under-hood fuse box. The voltage is about 13.8, which shows that the DC-DC working. Note that the potbox sitting on the headlight, still not routed into the passenger compartment.

At this point I felt that EV urge to try spinning the motor.

Yay! The hub spins and the controller didn't blow up. This means I actually got several things right. Okay, time to clean up this spaghetti wiring.

Here is the cable for the potbox routed through one of the rubber plugs in the firewall on the passenger side.

The cable from the potbox wasn't long enough to extend all the way into the engine compartment, so I found some shielded 4-wire cable and made an extension cord by using red male and female fast-on connectors. This is a picture of the passenger footwell. The potbox is to the left in the driver footwell and the cable goes forward, through the rubber plug in the prior picture to the driver components.

Her is some of the wiring after a bit of cleanup. I drilled several 1/8" holes in the front edge of the plastic mounting board and used these for tie-wrap holes to bundle the cables together.

Here is a closeup of the bundled cables nearer to the integrator module. It's not pretty, but I think it'll work. Note the BatMon board below, connected to the IsoBatMon circuit with its 7.5A blade fuse. In the lower-left of the photo, you can see the blue male/female fast-on connectors I used to connect the charger to the orange cable going to the charging socket on the outside of the car.

Routing the Cables Underneath

2008-12-03T18:23:00.001-08:00

Not surprisingly, we need to connect the batteries in back with the batteries in front and also include the main circuit breaker under the parking brake. These lines are typically routed under the car in the trough left by the exhaust system.

Many people use pool tubing to protect the battery cables from road dirt. After looking at the tubing selection at the local hardware store, I opted to use reinforced radiator hose tubes (outside diameter 1", inside diameter 3/4"). These hoses were cheaper than pool tubing and were more built for the harsh automotive environment. The were also more flexible so I could bend them around corners to properly route the cables.

I'll have to add more pictures later of this, but here's a good shot from under the car of the cables inside the radiator hose. I used hose mounting brackets bolted into the existing studs that held up the exhaust shields. Note the break in the cable near the center of the picture to attach to the high-current circuit-breaker. I tie-wrapped battery terminal covers over the breaker connections to protect them as well.

In the background is my trusty 914 EV charging up (power cord on the right side) for the next run to the hardware store.

While not pictured, the battery cable enclosed in radiator hose snakes back to the two holes on either side of the trunk just behind the rear seat. These holes previously had plastic plugs in them, but they now have grommets for the battery cable. The last picture in this post shows where the cables come up through.

This is one of the neighborhood students named Joseph. He drops by to watch whenever he sees me working on the car. Our interactions are noteworthy because he only speaks French and I only speak English. He helps out when he can despite our language barrier.

Wiring up the Vacuum Pump

2008-12-03T18:20:00.000-08:00

One of my goals for this kit was to utilize as much of the existing infrastructure of the car as possible in terms of fuses, relays and wires. To properly wire up the Gast vacuum pump, I wanted a fuse for safety and ideally a relay to protect the pressure switch from arcing too much.

Fortunately, the Civic had the features readily available for this in the form of the radiator fan circuit. The under-hood fuse box had a fuse and relay for this. The whole circuit was powered when the driver turns on the key, so the pump won't run with the car is parked.

This is the radiator fan connector. The black wire is ground and the black/red-stripe wire comes from the relay that powers it. I was able to cut off this connector and strip away the plastic protective sheath to use these wires.

Here is the black/red power wire connected to the positive side of the vacuum pump.

The radiator fan is triggered by a temperature switch connected to the green wire in the engine wiring harness. I was smart enough to leave many of the leftover harness wires intact and bundled up. The bright yellow wire on the left connects to one side of the vacuum pump switch.

I tied the negative side of the vacuum pump and the other side of the vacuum switch to ground via this existing 6mm bolt. The bolt is bottom center in the picture above with grey and blue wires attached to it with a 1/4" hole ring terminal.

This worked out quite well. When I turn the ignition key to the "on" position, the pump starts right up as the vacuum switch activates the relay. Both the pump and switch are fuse protected by existing fuses in the car.

Installing the Batmon Resistors

2008-12-03T18:17:00.000-08:00

In order to shunt current around each fully charged battery, the BatMon boards use an external 3 ohm resistor. Since mounting these resistors involves drilling holes in metal, I wanted to mount them before mounting the BatMon boards to prevent metal shavings from sprinkling into the electronics.

Here are two pictures in the rear trunk showing the drilled holes for the resistor mounting bolts. The BatMon resistors have mounting holes 2" apart that take 10-24 bolts. The Belktronix instructions suggest drilling holes and then tapping them with threads to support the bolts. Since I had a pile of 10-24 rivnuts and rivnut tool from a prior EV project, I decided to use them instead. The top picture shows two holes just over the large red battery post cover. The bottom picture has two holes in the upper left and two holes over the wingnut in the right side of the picture. Each set of two holes will hold two resistors stacked on top of each other.

Here is a view in the engine compartment where the 12V car battery used to be. I drilled four holes here to mount two pairs of resistors.

After drilling the holes, I used the rivnut tool (in the foreground with red handles) to press in four 10-24 threaded rivnuts.

In order to mount the resistors for the two front batteries (just behind the radiator grille), I had to unbolt the large piece of plastic holding up the charger and controller. With this raised, I could squeeze in the drill to produce the two holes on the inside vertical wall just behind the radiator grille. I'll try to note in the open-source instructions that these holes should be drilled BEFORE mounting the plastic and components. I guess hindsight is 20/20...

With the holes drilled and rivnuts installed, I then used 10-24 bolts 1 1/2" long with lock washers to bolt in each pair of resistors.

Here are the mounted pairs of resitors in the trunk. These resistors have fast-on connectors that will attach to each BatMon board.

Since the resistors get quite hot, I've been informed (thanks to Bob K.) to use bare fast-on connectors with heat-shrink tubing around them instead of the fast-on connectors with a plastic covering. The plastic covering tends to melt or burn, causing a mess.

Crimping the Battery Cables

2008-12-03T18:15:00.000-08:00

One of the major tasks during construction of an EV is properly crimping all the heavy duty battery cables together. Here's the process that I used.

I measured the distance between the terminals that I needed to connect, subtracted 1/2" and then cut a piece of 2/0 gauge welding cable for that distance. Welding cable is much more flexible than typical 2/0 gauge wire, allowing it to snake around various car parts.

The picture here shows a piece of cable and a special cable stripping tool. In addition to just cutting the cable to proper length, I marked the proper orientation on the cable for the lug at each end with a permanent marker. Once the lugs are crimped on, it's very difficult to twist the cable to get the lugs to fit.

With the tool (you can use a sharp utility knife too), I stripped off 3/4" of insulation.

I then squirted a good dose of Noalox anti-corrosion compound into the 2/0 lug needed for the connection. Make sure to smear the compound with the tip of the bottle all around the inside of the lug to get good protection.

I also smeared a bunch of Noalox on the ends of each cable and worked the compound into the braids. It's a good idea to protect your multi-hundred-dollar investment of cable and lugs with a $7 bottle of Noalox. The Noalox will also make your connections better and last much longer in the harsh automotive environment.

On my previous electric vehicle, I missed putting Noalox on four battery cable connections. After about two months of driving, these connections developed a high resistance and sapped my power during acceleration. After cleaning them up and adding Noalox, the car performed better and it's been fine for several months now.

Okay, with the cable and lug all gooped up, I needed to hold it steady for the crimper. If you have a partner, they can do the job. I didn't at the time, so I used a large plastic clamp and a chair to hold the cable like this. Make sure the orientation of the lug lines up with the marks you put on the cable.

With the cable and lug steady, I can now crimp it into place. Fortunately our local EV group has a crimper, stripper and cable cutter set that we share for people building EVs. These crimpers are often $350 or more, but are well worth it if you can spread the expense around.

Once the lug is crimped on the cable, project the joint with heat-shrink tubing. I use 1 3/4" lengths of tubing for the cables.

Here's the heat-shrink tubing in place, filling in all the gaps to protect the cable from corroding.

Here's a picture of the rear battery compartment with several cables attached. I also added Noalox compound to the battery terminals to keep the connections protected.

Here's where the flexible welding cable really shines. I mounted the contactor just over the motor and near the controller and most-negative terminal of the battery pack. With the flexible cable, I'm able to bend things into place.

Note: I used 2/0 gauge lugs with 3/8" holes for everything except the two lugs on the contactor (closest to the viewer in the picture above). These had smaller (1/4" holes) due to the smaller holes on the contactor. If I had used the larger holed lugs, they would have slid into the contacts and caused a contactor failure.

Installing the Charging Outlet

2008-12-03T18:12:00.000-08:00

At some point, I guess we have to charge this thing. Most people like to be clever and put the charging outlet under the gas tank cover. I don't like this because it's near the back of the car, away from most charging station outlets at parking spaces. It also requires more routing of wire to get to the charger.

Instead, I chose to simply cut a hole in the side of the front bumper and use a charging outlet from a boating store. The cable from the outlet to the charger is only 24" long and this is more convenient for plugging into a charging station with the cord dangling lower to the ground.

I purchased the charging outlet from West Marine (my favorite overpriced EV parts store) for $27. It required a 1 7/8" hole. I had a 1 3/4" hole saw, so I used it and then just used a rasp file to enlarge the hole as needed.

Here's a piece of leftover cord from my 914 EV and the Marinco charging outlet (upper left in picture).

You need to make sure you thread the ring nut and sealing cup on the cord BEFORE you slide it through the hole so that it will mount correctly.

With the cord through the hole, I can put the wires into the socket and screw them in tight.

Here's the final installation of the socket with lid. I like the clean look of this.

Back up over the passenger-side headlight, we can see the orange cord dangling over the edge. I cut off most of the charging cord from the Belktronix charger and used female blue crimp connectors to splice in the two tiny black fan wires (coming down from the top left in the picture) into the 120V line. By crimping blue male fast-on connectors to the orange cord, I connected everything together. I'll test this out later.

Mounting the Batmon Boards

2008-12-03T18:11:00.000-08:00

The next step involved preparing all the mounting hardware for the BatMon boards that sit on top of each battery. These boards monitor the voltage on each battery and signal back to the charger or the controller if there is an undervoltage (<10.8V) or overvoltage (based on temperature) condition.

The Belktronix kit comes with a bag of tie-wrap mounting pads and instructions to cut the pads in half to hold the BatMon boards to each battery.

Here's one BatMon board and its mounting pieces. The temperature sensor for overvoltage protection is on the end of the wire extending out the top of the picture. The instructions say to cut the tie-wrap mounting pads in half. I found that the remaining plastic tabs on the top of the mounting pads didn't really hold the BatMon boards that well, so I used wire cutters to form-fit the edge of the plastic tabs to the electronics on the board.

Here is the board mounted between the plastic tabs. Notice that the tab on the right just has a diagonal chamfer taken out to accomodate the green LED. The tab on the left needed a bit more work to fit between the red LED and the optoisolator.

Here are all the tie-wrap mounting pads from the kit with form-fit cut tabs, ready for BatMon installation. The smaller mounting pads near the top of the pile hold the temperature sensors onto the battery for proper sensing.

Fixing up the Rear Suspension

2008-12-03T18:09:00.001-08:00

Whew! I finally got my internet connection back up at home. This is the first of ten entries that will attempt to show many of the tasks I performed over the four-day Thanksgiving weekend.

First up, we need to beef up the rear suspension to handle the extra 420 pounds of batteries in the trunk. As you may remember, I swapped out the front springs with beefier ones. Since the old front springs were much stronger than the existing rear ones and had the proper taper to them, I opted to take the same route as Rob Connelly and cut them to handle the appropriate rear load.

Rob used six Optima Yellow Top group-31 batteries in his trunk. Since I'm using Concorde Lifeline batteries which are 9 pounds heavier each, I needed to support 54 additional pounds on the rear suspension.

Using Rob's spreadsheet, I was able to calculate the proper spring length from the old front springs that would handle the load. Many thanks to Rob C. for explaining spring physics to me and providing the spreadsheet. You can see a discussion and the spreadsheet in the Google discussion at this link.

After modifying the spreadsheet, I realized that I needed to cut the old front springs to 13.3" long.

Here is one of the old front springs in my cutoff wheel saw. There were quite a bit of sparks, but the wheel did an excellent job of making a nice flat top to the spring coil. Since the cutting process is very hot, I added an extra 1/10" to the cut length just in case the heat softened the top of the spring.

Here are both springs cut off to 13.4" length (13.3" plus the .1" for heat sag).
After cutting the springs, I removed the two rear shock strut assemblies and took them to Les Schwab to swap out the springs with the cut ones above. Several months ago, I had purchased a spring compressor to do this myself, but found it really scary given all the pressure. I found that just having the guys at Les Schwab do it with the proper equipment was $30 well spent.

Here is the spring assembly on the ground with the newly cut spring inserted.

Note: when you replace the springs, make sure you mark the orientation of the shock tower mounting bolts (left end of the assembly in the picture above) and the swing arm mounting bolts. Shock assemblies rotate and if you get the top and bottom bolts back with a different alignment, it's really hard with the spring under tension to rotate the top into the proper orientation.

Here's the spring mounted in position. Follow the instructions in the Helm shop manual to properly remove and install these. You need to raise the rear support with a floor jack to put the car's weight on the spring before tightening all the bolts, otherwise it doesn't sit right.

Since I had all the wheels off, I felt it was a good idea to check the front brake pad thickness. This is a close-up of the passenger side front wheel hub. I still have 9mm of brake pad left, which ought to be plenty for awhile. I will have to watch this since the extra 840 pounds of batteries will put an extra load on the brakes.

Movies of the First Test Run

2008-12-01T18:31:00.000-08:00

Well, my home internet connection is still down, so I uploaded a few videos here for your viewing pleasure and to prove that I'm not just blowing smoke :)

Thanks to my friend Rick for capturing these on my small camera. These are unedited and Rick tended to rotate the camera a bit. I'll probably make something more refined later...

Here is a quick tour of the major components under the hood.

Here is the Civic backing out of my driveway and taking off. It's nice and peppy!

Here is the Civic coming back down the block with some comments about its abilities. The loud buzzing is the vacuum pump for the braking system (hmm, rather loud).

I should be posting several pictures of my work over the next few days.

Cheers,
Tim

It's Alive! Updates coming...

2008-11-30T09:36:00.000-08:00

Okay, the cat is out of the bag. I've been working many hours a day over this four-day weekend to try and get the Civic running. As luck would have it, my internet connection went down Thursday morning and is still not back up (I'm typing this from work). I'll post all the progress and pictures when my connection comes back.

Suffice it to say, I'm exhausted, but the wheels are spinning as of 12:15pm yesterday(Saturday). I still have some charger connections to finish, but things look good at this point. If I'm lucky, I'll take it for a spin around the block this afternoon.

Cheers,
Tim

Arranging the Electronics

2008-11-26T07:38:00.000-08:00

The next step was to figure out where to put all the control electronics under the front hood to minimize wiring.

The Belktronix system comes with velcro attached to the underside of most of its components. I was able to fit the Integrator and Charge Controller in the passenger-side nook, next to the main charging unit. I attached the IsoBatMon circuit to the top of the closest AGM battery (right side of photo) to minimize cable runs.

Also, notice that I kept the thick wire that came from the alternator (thick white wire in lower-left of photo). I plan to re-use this to take current from the DC-DC converter (hmm... just like the alternator...)

Several of the fast-on connections on the Belktronix components are really tight (like the double blade connectors). After feeling uneasy about forcing the existing crimp connectors into these tight holes, I took the advice of another Civic EV converter (Bob Kaiser) and replaced the plastic enclosed crimp connectors (on the left) with bare ones (on the right).

To keep all conductive surfaces unexposed, I added heat-shrink tubing to the bare crimp connectors (sorry for the blurry picture). These slid right into the double blade receptacles without any undue force.

Next up: more wiring!

Buying Heavy Battery Cable

2008-11-21T10:56:00.000-08:00

I spent last night visualizing how I could most effectively connect all the traction batteries with the least amount of welding cable and the shortest distance to the controller and motor.

This morning I took some thick rope to serve as a fake battery cable and used it to measure the long cable lengths needed to connect the front and rear batteries. Measuring this is important because welding cable is expensive and you need to get enough but not too much. Here are the measurements I came up with:

Rear battery rack:

battery 1 to 2: 6"
battery 2 to 3: 12"
battery 3 to 4: 6"
battery 4 to 5: 12"
battery 5 to side battery: 14"
battery 5 underneath car, through the circuit breaker to the contactor: 16 1/2 feet

Front batteries:

front battery 1 to 2: 6"
front battery 2 to firewall battery 1: 34"
firewall battery 2 to 3: 6"
firewall battery 3 to 4: 6"
firewall battery 4 underneath car to rear battery 1: 13 1/2 feet

Controller connections

controller to motor: 19"
controller to front battery 1: 14"
controller to contactor: 8"
contactor to motor: 15"

All in all, I calculated about 44 feet of welding cable. I already have 13 feet, so I purchased 33 more feet to have a little extra. For those in the Portland, OR area, I highly recommend United Welding Supply up on MLK for 2/0 cable. The price is based on the commodity price of copper and was $2.90 a foot today. This compares to $4.75/ft from Electro Automotive, $6.00/ft at Parkrose Hardware and $8.85/ft at evparts.com.

I also dropped by Napa Auto parts to pick up all the fuse holders required for the BatMon battery monitors. I'm thinking this is going to end up like wiring spaghetti, but we'll see.

Have a great weekend, everyone.
Tim

Hacking the Final Hold-downs

2008-11-19T21:28:00.000-08:00

I installed the remaining hold-downs for the 12V auxiliary battery and the extra battery in the rear trunk this evening. I hadn't designed these hold-downs before I sent all the pieces off to powder-coat, so I'll have to paint them with POR-15 protectant before I finish.

Here's a picture of the 12V aux battery hold-down. The battery is a smaller motorcycle battery. The bar across the top is held down by a 3" piece of 5/16" all-thread with 1 5/16" spacing between the bar and the hold-down for the traction battery next to it. It turns out this is five nuts and a 1/16" thick washer.

Looking the other direction, the other end of the hold-down bar is simply held down with a piece of 5/16" all-thread going down to a hole we drilled in the last post (see third picture down in the last post).

This is a view underneath the passenger side of the car looking up at the 12V aux battery (which looks scratched up alrady). The nylock nut in the center right caps off the 5/16" all-thread above and holds it in place.

Here's where the extra battery in the trunk sits on the passenger side. I cut a 15" long piece of 1" wide steel bar (1/8" thick) and drilled a 5/16" hole in each end 1/2" from the end. I laid this piece down where the battery sits and marked through the 5/16" holes. The rear-most hole sits right on top of rear-most structural bulge. The front hole sits just in front of the forward-most bulge.

After marking the holes, I drilled them with a 11/32" bit so the holes would be a bit larger to allow a bit of inaccurate drilling.

Here are two pieces of 11 3/4" long 5/16" all-thread. I used regular nuts with washers on the top side.

Here is the underside of the car with the two pieces of all-thread through the holes in the 1" bar we laid out earlier and capped off with nylock nuts.

With the all-thread in, I added a piece of 3/4" angle iron with 11/32" holes drilled in it through the angle-iron corner at each end. It's held down with a washer and wing-nut. Drilling the holes in the corner of the angle-iron was rather tricky; I had to use four progressively larger drills to get the final hole size without the drill corner binding on the inside faces of the angle-iron.

I think I'm finally done with the vast majority of the mechanical design. I'm tired of designing mechanical things and just want to wire this puppy together. Let's see what we can do tomorrow.

Charger, Controller and Contactor Mounting

2008-11-16T15:14:00.001-08:00

Today involved trying to mount the major electrical components to the car.

Before covering up the transmission, I thought it would be a good idea to fill it with transmission fluid. The Honda Civic specifies 10w-30 oil for the transmission. Since the fill hole is really hard to access, I used a funnel attached to a plastic hose to get the oil in.

Before mounting the plastic panel to mount the EV components on, I drilled two 3/16" holes, 6 3/4" apart on the passenger side battery support. This will be used to mount the large 3-ohm resistor used by the charging system.

I still haven't figured out the hold-downs for the cars 12V auxiliary battery or the extra battery in the rear trunk. Since access will be more difficult after I install the EV components, I drilled a 5/16" hole (top center in picture) in the passenger side front battery support iron. I think I can use 5/16" all-thread with some angle iron to get this hold-down working.

Okay, on to mounting the control board plastic. As we stated before, this plastic is 1/2" thick, 28" long and 8 1/2" wide. I clamped it in place with a plastic clamp to prevent marring the surface. I placed the main contactor near the right edge, approximately centered front-to-back.
With the the plastic and contactor in place, I scratched circles in the plastic for the two 3/16" contactor mounting holes and underneath the plastic in all the 1/4" mounting holes from the angle-iron that juts out.

Afterwards, I removed the plastic, and drilled out all the holes (3/16" for the contactor, 1/4" for the board mounts). I used a countersink bit to taper the bottom of the contactor holes so the bolt-heads would be flush with the bottom side of the plastic. I also countersunk the top-side of all the 1/4" holes so that the main mounting bolt heads would be flush with the top-side of the plastic. By making all these bolt heads flush, I don't interfere with any components or support angle-iron.

Here's the plastic installed on the angle-iron supports and the contactor in place. I used six 1/4" flathead bolts 1" long for the main supports and two 10-24 x 1" long flat-head bolts to mount the contactor. All bolts were held in place with nylock nuts.

With the plastic mounted, I placed the charging unit and controller unit on the plastic. The front edge of each component was 3/4" from the front edge of the plastic. The charger was on the passenger side and its heat-sink fins aligned with the inside vertical wall of the passenger-side angle-iron support. The controller unit sat between the charger and the contactor with 1/4" of clearance between the heatsinks. With the two units in place, I dropped a 1/4" bolt down through the mounting holes and marked the plastic.

After removing the units, I drilled out the 1/4" holes. The hole closest to the passenger seat had to go through the plastic and the metal support. After drilling these holes, I bolted the components to the plastic using 1/4"-20 x 4" long bolts with washers and nylock nuts underneath. The rear bolt on the motor controller was very close to the transmission housing, so I added some spacer washers to raise up the bolt a bit to prevent interference.

Whoops! I accidentally mounted the contactor with the activation terminals on the high-voltage side, so I had to disassemble the whole thing, flip the contactor around, and re-install it (shown correctly here).

Here's the final installation with the two main EV components and the contactor on the right.

The last item of the day involved installing the large 3-ohm (90 watt!) power resistor on the passenger side angle-iron support. This simply used two 10-24 round-head bolts 1" long and nylock nuts. I thought it would be easier to wire with the terminals up, so we'll see.

Next up: mounting all the small EV control boxes

Re-Using Computer Wires

2008-11-15T08:41:00.000-08:00

The Belktronix system instructions call for attaching all the Batmon boards with twisted pairs of wires. I couldn't find a spool of twisted wires at the hardware store, but it dawned on me that most desktop computers use twisted wires to connect the motherboard with the switches/LEDs on the front panel. So, I went over to my friend non-profit computer recycler FreeGeek and picked up a handful of twisted wires out of their wire recycling bin for $1. This is great because I get a huge variety of colors and a few LEDs and small switches included. I even got a ferrite core that could be useful for reducing noise.

In short, if you have a local computer recyling place, there are tons of colorful twisted pair wire sets available.

Component Placement on Plastic Control Board

2008-11-14T16:08:00.001-08:00

With all the components under the firewall rack installed, I put the four remaining batteries in the rack and started figuring out the placement of parts on the control board.

Here is the tentative placement of charger and controller. The contactor is off to the far right. I purchased a piece of black "UHMW" plastic (28" long x 8 1/2" wide by 1/2" thick) to mount the components on. My EV cohort Ron used this plastic in his VW Jetta EV at Shorepower Technologies and it seems to work well.

I wanted to put all the high-current, high-voltage cables on the right, so the controller, contactor and motor terminals are all over there. The charger/DC-DC converter is on the left. I'll put the AC power inlet on the passenger side bumper and velcro the system integrator and charger monitor in the remaining space behind the passenger side headlight.

I still have to re-assemble the drive-shafts and suspension underneath the car, but much of the mechanical work is getting close to complete. Based on the detailed instructions in the Belktronix installation manual, I think the wiring will go fairly smoothly.

Starter Blockoff Plate Template

2008-11-14T10:00:00.000-08:00

I took some time this morning to finish all the vacuum pump connections and installing the wiring harness discussed a few posts back. Before installing the batteries in the firewall rack, I needed to measure the starter block-off hole to make a cover for where the starter motor used to be.

Here's the engine compartment with the engine wiring harness plugged in and tie-wrapped to several locations. It's hard to see, but you can just make it out as a black tube with pieces of red electrical tape on it. I tested out the vacuum pump system by attaching the pressure switch and connecting a small 12V UPS battery. It seems to work fine, but I have a small leak at one of the fittings. I probably need to put some vacuum grease around the fittings where the hose connects to make a tight seal.

Here's a .jpg file of a rubbing for the starter blockoff plate. It's accurate at 100x100dpi. If you click on the picture to enlarge it and save the result, you should be able to print it out (in MS-Paint or something like it) and get a pattern for your own transmission. Don't forget to tell the paint program that the picture is 100x100dpi and print it out a 100% scale.

Since I have the original rubbing, I'm going to simply trace it out on this 1/16" piece of steel I found and cut it out with a sabre saw. The two bolt holes are 10mm in diameter. Others might just do their own rubbing instead of using the template above.

Here's the starter block-off plate installed underneath the firewall rack. The heavy bolt on the upper right is overkill but came from the original car. The lower left bolt holds the transmission to the motor adapter plate.

Charger/DC-DC Arrives

2008-11-14T09:52:00.000-08:00

The last piece of equipment from Belktronix arrived today.

Here's the charging system from Belktronix. The 1200 watt charger is combined with the DC-DC converter on the right. The small black box on the left is the charge controller box which interfaces with all the Batmon units that monitor the voltage on each battery. I'm psyched that I finally have all the critical pieces and nothing left is holding me back.

Last week, I also dropped by my favorite overpriced EV parts store: West Marine. This is a 15 amp charging inlet used for boating. This will fit nicely on the front right bumper to allow me to plug in without opening the hood. Many people use the space behind the gas-tank cover for their charging inlet, but I much prefer it near the front of the car because that's where all the components. Having the inlet on the front also makes it much closer to the ground and closer to the charging station if I'm parked front end in.

Preparing the Engine Wiring Harness

2008-11-09T16:06:00.000-08:00

Before I can put in the firewall batteries and start hooking things up, I need to finish cleaning up the engine wiring harness.

Here's what's left of the wiring harness after I removed all the things I didn't need. In the middle of the harness on the right is a nine-foot long loop of 4-in-1 automotive wire (16 gauge) that I'm going to attach to several wires as an extension so that I can easily route everything to the EV controller board in front of the firewall batteries.

The only items left are:

C104 - starting wire (black/white on harness, white on 4-in-1 wire)
C106 - 12V keyed power (black/yellow on harness, green on 4-in-1 wire)
C108 - temperature gauge sending wire (yellow/green on harness) - dangling
C110 - backup-lights - connector on transmission
C112 - speedometer sending wire - connector on transmission
C118 - oil light (yellow/red on harness, yellow on 4-in-1 wire)
C119 - battery light (white/blue on harness, brown on 4-in-1-wire)
C124 - main wire harness connector (2 thick wires)
C126 - main wire harness connector (14 small wires)

After I cleaned things up and covered everything with flexible cable cover, I'm left with the two main wire harness connectors in the lower left, the backup and speedo connectors in the middle right, and the 4-in-1 wire that will go to the EV control board in the upper right.

After I get some tie-wraps tomorrow, I'll thread this through the engine compartment.

That's it for the weekend... I'm wiped.

Installing the Vacuum Pump

2008-11-09T13:29:00.001-08:00

I installed the Gast vacuum pump and pressure tank next.

First, I installed rubber motor mounts underneath the Gast vacuum pump. Since I'm mounting this on uneven pieces of metal, I needed to add two 1/16" thick 1"dia. fender washers to the two feet on the front. The rubber feet serve two purposes: keep the motor vibration from rattling the chassis and raising the pump to clear the supporting angle iron. The rubber feet are 1" in diameter, 3/4" tall (rubber portion) with 1/4" threaded ends.

After installing the rubber feet, I put the pump in place and marked the holes on the supporting angle iron. After drilling 1/4" holes, I placed a 1" dia. fender washer (1/4" hole, 1/16" thick) on each of the holes to give the pump enough height to clear the vertical wall of the angle-iron on the right side of the picture.

Here's the Gast vacuum pump installed. I'll figure out the wiring diagram later.

The next step is to mount the vacuum chamber. I tried several locations but found that under the firewall rack was the most convenient. I drilled two 1/4" holes 21 1/2" and 23 3/8" from the passenger side end of the middle-rear horizontal angle-iron support for the batteries. This should place the tank between the control board supports that jut out at 17" and 27" from the passenger end.

Since these mounting bolts will be under the batteries, I countersunk the holes with a 3/4" countersink bit (see drill in background).

Here is the bracket that holds the vacuum chamber. These are 1/4" tapered flat-head bolts 5/8" long with two nylock nuts.

Before installing the vacuum chamber, make sure you align the nipples for all the hoses correctly. The top nipple goes to the brake chamber. The middle nipple (black) has a one-way valve to keep a vacuum in the chamber after the pump shuts off. The black one goes to the Gast pump. The pressure valve is attached to the bottom opening.

Here is the vacuum chamber installed under the firewall rack behind the Warp9 motor.

The next task is to get the vacuum line from the brake chamber down to the vacuum chamber. I like to reuse as much as possible, so I undid the clamp for the hose on the brake chamber and rotated the hose counterclockwise about 90 degrees. This puts the free end of the hose across the brake cylinder and down behind the firewall rack.

I also undid the clamps on the piece of hose farthest away from the brake cylinder and flipped it around so that the angles in the hose more closely matched the contours of the car. The grey module inline with the brake vacuum hoses is another one-way valve that keeps vacuum in the system.

With the original brake vacuum line snaked behind the firewall rack, I was able to attach the other end (with some minor bending) to the brass nipple on the vacuum chamber. I'll use the remaining vacuum hose that came with the Gast pump setup to attach the black nipple to the inlet on the Gast pump.

Whoosh, this has been a busy weekend. I'll see if I can get the engine wiring harness prepped before it ends.

Installing the Circuit Breaker

2008-11-08T20:39:00.000-08:00

Remember that huge Airpax circuit breaker that I got in the mail? Well, it's time to install it.

I learned how to remove the center console cover by reading the Civic shop manual. Here I've removed the cover and am holding back the driver's seat to show a better view. In hindsight, I had to remove the driver's seat and it would have been a good idea to do it right at the start. Things were really gross under here with spare change, coffee spills and lots of garbage. Ick!

After vacuuming things up, I cut out the rug piece just behind the mounting bolts.

Here's the rectangle where the Airpax will be mounted. The left edge (towards the front of the car) is 3/4" rearward from the center-lines of the mounting bolts. The rectangle is 1 1/2" wide and 2 5/16" long. I released the parking brake and unbolted the handle (with cable still attached) for easy access to the console metal. The green wire is the parking brake switch, so don't forget to reconnect it when you're done.

After drilling four holes in the corners, I used a sabre saw to cut out most of the metal plate. At this point, I've removed the driver's seat and dumped it on the rear seat so I could get the sabre saw in there. Looking back, I should have removed the seat from the start.

Okay, after half an hour of filing (grrrrr), I got the Airpax switch to fit in the hole.

The airpax has two small threaded holes in the top. The holes are centered on the front and back edges, 1/4" from the edge.

I was lucky enough to have two bolts with washers from my last EV project that fit. Here is the Airpax circuit breaker installed and flipped to the "OFF" position.

I put the console plastic back on and cut out a plastic rectangle to enable flipping the switch. If I had rotated the circuit breaker 180 degrees, it would have sat forward another 3/4", possibly making it easier to access. The downside to turning it around is that the "OFF" position would have been forward. It's much easier for me to flick the switch to the "OFF" position if I can flip it towards the rear of the car, so I went with the above orientation.

Since it's just me working on the car, I had to hold the Airpax in place while I bolted it in. I used a stack of 2x4s with a long vertical one to accomplish this.

Okay, time to relax and think about how to install the vacuum pump tomorrow morning...

Installing the Potbox

2008-11-08T14:48:00.000-08:00

The Belktronix system tries to make installing the potbox a no-brainer by allowing the user to put it right under the accelerator pedal. For the Civic, this works out quite well.

Here are the heavy-duty Velcro pieces that come with the Belktronix kit. The intent is to put the "hook" side of the Velcro on the rear side of the potbox and simply stick it to the rug under the pedal.

I found that the rug moved around quite a bit, so I wasn't comfortable sticking the potbox directly to the rug. In the above photo, I've cut away the rug and the rubber pad underneath the rug to expose the firewall metal under the accelerator. I want to line up the bulge on the backside of the accelerator pedal with the plunger on the potbox. There's a seam with a right edge and bottom edge shown in the photo above. Mark a horizontal line 3/8" above the bottom edge of the seam, and align the potbox with it and the right edge of the seam.

Clearance is tight, so I added the "hook" sid of the Velcro to the backside of the potbox between the assembly bolts.

To get the "fuzzy" side of the Velcro to line up on the firewall, I just pressed the fuzzy Velcro onto the "hook" Velcro attached to the potbox and just pressed the whole assembly into place under the pedal. Again, the bottom edge is 3/8" above the bottom seam and the right edge lines up with the right seam.

Here's the potbox installed with the bump of the pedal resting on the plunger. There are also some small "L" brackets in the kit that I could also use to mount the potbox to the firewall, but I'll try the Velcro version first and see if it sticks (pun intended).

With the potbox mounted, I need to find a way to route the potbox wires into the engine compartment. After hunting around, I found this 25mm plug on the passenger side under the glove compartment. The picture above shows the plug (red arrow) from the engine compartment side. I'm guessing a 1" grommet would do just fine here. I could have drilled a 1" hole in the firewall, but I think this is cleaner.

Since we're on the topic of routing cables, I thought about how to route the high-current battery cables from the front engine compartment to the rear battery rack area. It turns out that there are also two 25 mm plugs (the ones we used to align the front bolts) in the rear area that line up neatly with the ends of the batteries. I figure I can route the cables under the car and tie-wrap them to various brake lines down there and they will come up through these holes (with grommets added) to attach to the batteries.

The next step will be to figure out how to attach the vacuum pump or extend the engine wiring harness to reach all the places we need it to.

Onward!

Installing the Powdercoated Racks

2008-11-08T14:21:00.000-08:00

The past two days have been productive. I went to Class Act to pick up the powder-coated angle-iron and installed most of it.

Here are the powder-coated pieces all nicely wrapped up to prevent damage.

Here are the pieces unwrapped. Yep, all 39 pieces are there and in good condition.

I started by installing the rear battery rack. The two cross pieces of angle-iron sit on top of the two square tubes. The bolt going down through the angle iron sits several inches away from the end. I taped the bottom face of a box wrench and inserted a nylock nut (see picture above) so that I could tighten the bolt into the nut.

Here is the rear battery rack installed, without the wood insert. I cut 10" pieces of 5/16" all-thread for the hold-downs and installed them. I had difficulty installing the two pieces of all-thread between the shock-towers due to lack of clearance under the angle-iron for the nylock nuts. I had to use two thinner "jam" nuts in order to install these last two all-thread pieces.

Here's the rear rack with the batteries on top of the wood plank and hold-downs installed. I still have to devise a system to hold down the extra battery on the right, but I think there are off-the-shelf automotive solutions for this.

The next step was installing the rear motor mount plate and bracket to the driver-side engine mount. I bolted the rear plate on with 5/16" bolts (threads had red loctite) and lock-washers. With the plate on, I could use the engine hoist to raise the whole assembly into place. After bolting in the transmission on the passenger side, I bolted together the bracket on the driver-side. All in all, I'm pretty happy with how it blends in with the black chassis of the car.

Here's the motor/transmission assembly fully installed. I have a portion of the original engine wiring harness plugged in to get a feel for what I'll have to deal with electrically. I'll add more pictures in the future after I figure out how to tap into this.

Here are the firewall-rack angle-iron pieces installed. Are are some dry details about what I used to hold it together:

6mm bolts (20 mm long) with lock washers hold up the vertical bars to the shock towers
3/8"-16 bolts, 1" long with nylock nuts hold the left and right angle-iron supports to the vertical bars
5/16"-18 bolts, 3/4" long hold the four horizontal angle-iron pieces to the driver-side support.
On the passenger side, the horizontal pieces are bolted in with 5/16"-18 bolts (3/4" long) only on the two middle pieces.
The rear-most and front-most horizontal pieces are bolted to the passenger-side support with 5/16" all-thread, 10" long, which also serves as hold-down support.
The front-most and rear-most horizontal pieces have 5/16" holes 27" in from the passenger side. I inserted 5/16" all-thread to serve as hold-down support and to attach the control-board support that juts out towards the viewer in the picture.
The remaining control-board piece that points toward the viewer in the center of the picture is held up by two 5/16"-18 countersunk flathead bolts 3/4" long with nylock nuts on the bottom. These have to be countersunk because the top surface needs to be flush with the angle iron to support the batteries.

Here is a top view of the front rack installed with hold-downs in place. I also used 5/16" all-thread 10" long for this. I probably should have used 9 1/2" long pieces. The driver-side all-thread closest to the grille has very little clearance, so I had to screw it downward in order to fit the small nut on the top (as opposed to wingnuts on the remaining three corners). Note: for some reason, Blogger is acting up and magically rotated the bottom picture. It is horizontal for easier viewing on my hard-drive.

Next up: installing the potbox

Battery Monitoring Parts

2008-11-06T19:36:00.000-08:00

I received several more critical items in the mail this past week.

Here are several components from the Belktronix battery monitoring system. In the upper left is the "batmon" unit (one for each battery) that monitors each battery. The black/white wire coming out of the top is a temperature sensor which adjusts the final shunt voltage based on the environment. The green LED turns on when the resistive shunt (lower left in the photo) kicks in to balance out the batteries. The red LED turns on when the battery voltage sags down to about 10.7 volts or so. This is far more effective than just monitoring the total voltage of the pack because the system has undervoltage protection for each individual battery.

Bryan at Belktronix came up with a great way to connect these modules together. There are four green snap-in connectors for each Batmon board that allow easy connection and disconnection for the individual functions:

shunt resistor
12V connection to the local battery
signals in parallel with each Batmon to indicate shunt active
signals in parallel with each Batmon that an undervoltage has ocurred.

The plastic bag in the upper right contains all the plastic mounting hardware for each batmon. These are standard tie-wrap holders with sticky bottoms. The "IsoBatmon" circuit in the lower right corner of the picture electrically isolates the signals from all the Batmon boards from the rest of the system for safety.

At this point, I'm only waiting for the charging/DC-DC system from Belktronix, which should arrive in a few weeks.

The other two parts I received from KTA-services were a 500-amp Ferruz-Shawmut fuse and a heavy-duty Airpax circuit breaker. Theoretically, I should only need one of these, but I'll put both in the high-current cabling for safety in case something shorts out. I plan the mount the circuit breaker under the parking brake like Bob Bath did in his CivicWithACord project.

On another bright note: I received a call from the powder-coating shop on Tuesday letting me know that they had already finished the job. I'll be going to get the finished parts tomorrow morning and seeing how far I can get with assembly.

I'm exciting to have all the parts needed to make significant progress. Let's see how much I can get done this weekend.

Sending Pieces off to Powder-Coat

2008-10-31T12:46:00.000-07:00

Last night I disassembled all the battery racks and gathered the pieces in the living room to get ready for powder-coating.

Here are all the steel angle-iron and bar-stock pieces in their approximate battery rack groups (39 pieces in all). I put them in the plastic bin to the left and drove them over to Class Act Powder Coating for powder-coating. For $100 they're going to sandblast all the paint and oxidation off and coat the pieces with epoxy to prevent rust and acid damage.

While it may not seem like much, the above picture represents several months of trial-and-error design work to fit twleve group-31 batteries into the limited space of the Honda Civic. I'm looking forward to the mechanical design being finished so I can focus on the electrical design, which is much more up my alley.

Here's the rundown of pieces:

Rear Rack:
2 square tubes
2 angle irons (notches on outside)
2 angle hold-downs with notches
2 bar hold-downs

Front Rack:
2 short angle irons
2 long angle irons
2 bars
1 short wide angle iron
2 angle hold-downs
2 bar hold downs

Firewall Rack:
4 short bars (notches start at driver, clockwise)
2 side angle iron
4 horizontal angle iron
2 support angle iron
2 side hold-down bars
2 angle hold-downs
2 hold-down spacers

Motor Mount:
1 heavy short angle iron
1 end plate

Happy Halloween everyone!
Tim

Making the Battery Hold-Downs

2008-10-31T08:53:00.000-07:00

I cut several pieces of metal for the battery hold-downs. The construction details are as follows:

All angle iron and barstock is 1/8" thick and 3/4" wide.

Front rack:
2 pieces of angle iron, 27 1/2" long with holes
2 pieces of iron bar, 7 1/16" long with holes

Trunk rack:
2 pieces of angle iron, 36" long , with notches described here
2 pieces of iron bar, 13 3/16" long with holes

Firewall rack:
2 pieces of angle iron, 27 1/2" long with holes
2 pieces of angle iron, 26" long (no holes)
2 pieces of iron bar, 14 1/16" long with holes

All items listed above "with holes" have a 11/64" hole drilled in each end, centered from side to side and 3/8" in from the end.

This description is terse as I'm trying to get the whole pile of steel out the door today for powder-coating. I'm an electrical engineer by training, so I'll be happy to get all this metalwork out of the way.

Redesigning the Firewall Rack

2008-10-25T15:46:00.000-07:00

After redesigning the firewall battery rack with rotated batteries, I wrote down some installation instructions. For the past two days, I've been following my own instructions to see how well they work out.

Here are the four 1" x 3/16" x 5.5" bars that will be mounted to the shock towers

With the bars mounted to the shock towers, I cut the left and right angle iron supports. I bolted the rear end through the 2 3/4" piece of 1" galvanized pipe and used a clamp to hold the front to the bars on the shock towers.

Here's a similar view of the supporting angle-iron, but on the driver-side. Note that I had to carve out a much larger notch out of the rear motor mount to accomodate the supporting angle iron. I also had to cut an angled piece off the back of the supporting angle iron to not interfere with the brake lines under the brake-fluid reservoir.

After measuring the distance between the two side pieces, I cut four horizontal pieces of angle iron, measured the proper distance between them to fit the Lifeline batteries and clamped them in place.

Same structure but on the passenger side. The rear-most horizontal bar has a curved piece cut out of it to avoid touching the brake lines. With all pieces clamped in place, I could now draw through the holes in the horizontal bars to the underlying metal to properly drill bolt holes.

After marking and the holes on the left and right supports as well as the bars mounted to the shock towers, I disassembled the structure, drilled the holes and bolted it back together. With the structure bolted together, I now added the two angle-iron pieces on the right that jut out towards you. These are just clamped in place so I can mark holes on the angle-iron pieces.

With the marked holes drilled on the rightmost angle-iron supports, I bolted the far right one on. These supports that jut out towards the front of the car will hold a platform for all the electronics.

Here's a final test to make sure the batteries fit in and I still have hood clearance. With the batteries in, I was able to close the hood easily without any interference. Yay! It took me awhile to get this solution to work.

Next up: making the hold-downs for the front and firewall battery racks.