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
Monday, January 3, 2011
Wednesday, June 16, 2010
Saying Goodbye to Electric Blue
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
Saturday, February 6, 2010
Analyzing PakTrakr Files with PrestoPlot
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
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
Thursday, February 4, 2010
Mounting the PakTrakr
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.
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.
Sunday, January 31, 2010
PakTrakr Signal Integrity
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:
Ugh, time to get ready for the week...
Cheers,
Tim
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.
Ugh, time to get ready for the week...
Cheers,
Tim
Sunday, January 24, 2010
Fixing the Batmon Resistors
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.
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.
Thursday, December 17, 2009
Seeing the Nissan Leaf in Person
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.
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.
Monday, December 14, 2009
When Things Fall Apart
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
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
Sunday, December 6, 2009
Replacing and Saving the Aux Battery
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
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
Saturday, December 5, 2009
Comparing Conversion Costs with Paul
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)
Thanks for assembling this list, Paul!
Tim
(click on the picture below to get a full size version)
Hints from Paul on Paktrakr Installation
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 just wanted to pass this information along to all of you.
Cheers,
Tim
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
Tuesday, December 1, 2009
Installing the PakTrakr, Dead Aux Battery
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...
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...
Friday, October 30, 2009
John's PakTrakr Display
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:
Looking forward to getting my PakTrakr back...
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,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.
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
Looking forward to getting my PakTrakr back...
Friday, October 16, 2009
Installing the PakTrakr
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 #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...
| 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...
Saturday, October 3, 2009
Range Anxiety
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:
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.
Saturday, September 5, 2009
New Vacuum Pump and Fixed Wiper System
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
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
Saturday, August 22, 2009
Controller Overheating and Vacuum Pump Issues
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.
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.
Tuesday, July 14, 2009
Getting a new Synkromotive Controller
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.
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.
Sunday, July 12, 2009
EV Awareness Day, Synkro faults
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...
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...
Thursday, July 9, 2009
Super FET working Comments on Sykro Controller
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.
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.
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