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.
Monday, December 8, 2008
Ordering Gauges
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:
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
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
- Link-10 e-meter from Affordable Solar
- Link-10 prescaler from Belktronix
- Link-10 DC-DC from Belktronix
- Zolox tachometer sensor from EVSource
- Warp9 mount for Zolox sensor from EVSource
- Small Equus Tachometer from Schucks
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
Saturday, December 6, 2008
Cleaning up Loose Ends
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
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
Friday, December 5, 2008
Wiring up and Testing Batmon Boards
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!
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!
Thursday, December 4, 2008
Fixing the Speedometer, Removing ECU
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!)
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!)
Wednesday, December 3, 2008
Buttoning up the Exterior
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
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
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.
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.
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