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Reposting, 86 Year Old Uncle Still Trying After 34 Years to get EV1-B Car Running

4340 Views 21 Replies 8 Participants Last post by  Electric Forklift Guy
To All,

I am reposting from last year asking for any available advice as me and my cousin continue to try to help get my uncle’s EV project started in 1984 to a successful conclusion.

I am still trying to help my uncle realize his main bucket list item while there is still time. He has been working off and on for over 30 years to slowly build an electric car. When he attempted to power it for the first time last year the controller failed to trigger the contactors to send power to the motor. He said all he wants to do is to drive this car at least once before he dies. He gets up every day and puts on his union machinist suit and goes to work in a construction company warehouse in Ludlow Massachusetts doing maintenance and machinery repair. He has started talking about retiring and would then need to find another location for the EV project car if it is not yet finished. So I was asked to come take a look. In my distant past I have a degree in electrical engineering and have experience with SCR controlled injection molding machines so theoretically I should technically understand all documentation and pretty much understand how things should work.


The car chassis was hand built:

http://ptandjb.com/eddiesEV1/carfront0491.JPG

http://ptandjb.com/eddiesEV1/carside0490.JPG

Overview of controller assembly:

http://ptandjb.com/eddiesEV1/EV1fullview0483.JPG

http://ptandjb.com/eddiesEV1/EV1closeup0485.JPG


I had thought last year we had proven that the EV1-B controller was defective and went back last month to try to disassemble and test the controller. We repeated our original investigation, with SEAT and BRAKE switches bypassed and KEY, FWD, and ACCEL switches appropriately set there was no contactor activation. Looking more carefully at the documentation, I realized that I had not considered STATIC RETURN TO OFF and PULSE MONITOR TRIP requirements, and could no longer conclude I had proven the controller defective. I was confused as the exact process (see confusing manual excerpts below). Because I was not up to speed on these requirements, we called it a day and I came home to study documentation and try to figure out a way forward. An initial successful outcome would be sending power to the motors in forward or reverse in START ACCELERATION mode.

From the manuals:

The control circuit is energized by closing the Key switch, Seat switch, and moving the Forward or Reverse lever to either position and then depressing the accelerator, thus closing the Start switch. This applies power to the control card and, if the ”static return to OFF” requirement and the pulse monitor trip requirement are satisfied, turns on the PMT driver, which will close the selected directional contactor, completing the circuit to the traction motor. The directional contactor is controlled by the directional switch.
· STATIC RETURN TO OFF — this built-in feature of the control requires the operator to return the directional lever to NEUTRAL anytime he leaves the vehicle and returns. If the Seat switch or Key switch is opened, the control will shut off and cannot be restarted until the Directional switch is returned to NEUTRAL. A time delay (0.5 seconds) is built into the Seat switch input to allow momentary opening of the Seat switch. This same delay requires the Directional switch not be closed until both the Key switch and the Seat switch have been closed for 0.5 seconds.
· PULSE MONITOR TRIP — this function contains three features: The look ahead, the look again, and the automatic look again reset.
If 1 REC (the main SCR) is shorted or lA is welded. PMT will look ahead and prevent F or R from closing if either condition exists.
If 1 REC fails to commutate, or if lA power tips remain closed when they should be open, the control will open F or R contactor. PMT will then look again by testing for a fault and, if none, reclose F or R. If the fault still exists, the F or R will reopen and remain open.
If lA closes before a second commutation failure, the look again counter will automatically reset. This eliminates the inconvenience of resetting the PMT with the key switch if the tripping is due to random noise.
When the PMT circuit prevents F or R from closing, the PMT circuit can be reset only by opening the Key switch.

I have uploaded various relevant files from various sources to my web domain in directory where they can be viewed or downloaded:

http://ptandjb.com/eddiesEV1

EV-1 Spec1.jpeg 1st page original EV-1 controller spec sheet
EV-1 Spec2.jpeg 2nd page original EV-1 controller spec sheet
EV1.pdf EV-1B Troubleshooting Manual & Parts Lists
EV1WireDiagram2.docx EV-1B Wiring Diagram as Word Document
EV1WireDiagram2pdf.pdf EV-1B Wiring Diagram as PDF Document
EV1closeup0485.JPG EV-1B close-up view
EV1fullview0483.JPG EV-1B full view
carfront0491.JPG front view car chassis
carside0490.JPG side view car chassis
ev1maint1.pdf GE EV-1 Troubleshooting/Repair Manual part 1
ev1maint2.pdf GE EV-1 Troubleshooting/Repair Manual part 2
ge_ev1_rs_notes.pdf Roger Stockton’s EV-1 SCR DC Motor Notes
ge_ev1_rs_notes.docx Roger Stockton’s EV-1 SCR Notes (edited)


Before our next trip to Ludlow to further evaluate the EV1-B, I have some questions:

Is there anyone familiar with the GE EV1-B controller willing to talk to me on the phone and/or correspond by email and/or make a visit to see the car to render technical assistance? All reasonable expenses would be covered. Also Facetime video call assistance is an option.

Is there a way satisfy/bypass/eliminate the PMT requirement to rule that out as a problem? I have trouble figuring how to understand its function.

If we prove a failure of the EV1-B controller does anyone have experience working on this unit?

If demonstrated defective, are there repair options available sufficiently local to Ludlow Massachusetts that can visit the site or are there sites we can bring or ship the EV1-B controller? A typical forklift repair technician may simply want to replace the EV1-B unit and not troubleshoot faults inside the unit.

Is there a source for spare parts/technical support for the EV1-B controller if we get inside the box?

Thanks in advance for help, if fortunate to succeed there will be a YouTube video of a successful outcome. This email will be cross posted at diyelectriccar.com and evdl.org.

Paul Traceski
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Hi


Your using a design of dc controller built for the 1970´s fork lift truck market. My background is military electronics and I believe you are becoming un stuck with age related problems. No semiconductor device has a life beyond 20 years, at which point it will fail or semi fail intermittently. Electrolytic capacitors have no life after approximately ten years, even less if they are unused (about 3 years) the ESR of them will rise to practically not represent a capacitor at all, the rest of the components i.e. resistors, polyester capacitors etc will deteriorate voltage wise and will either breakdown or short circuit. Cut a lot of heartache out and expense, purchase a modern dc controller, check your motor winding´s with a Megger (insulation tester) and replace if necessary. I know it is not the advice you were looking for but is the most practical and economical and the only certain way your Uncle will be able to drive his EV.
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the only certain way your Uncle will be able to drive his EV.
I have GE EV-1 controller from 1969. Works fine.

I don't think it even has electrolytic capacitors.

Semiconductors only being rated for 20 years.... come on man. 20 years ago was 1998. Yeah a few devices are going to go bad over time, but, it's not a plague (except for the capacitor plague, devices from early 2000s infamously fail due to attempted trade secret theft and counterfeit electrolyte failing).

It would certainly be easier to spend $100 on a little golf kart controller and be done with it, but, he's not condemned to failure just because he's using an old controller.
I run into running EV-1 on a regular basis.

Historically the most likely point of failure is the plug in the back of the oscillator card (the card that flips forward) FSIP.biz sells rebuilt cards to fix this problem
(they also have the tech manual for it as a FREE down load).

If the card does not try to close the directional contactors there are several possibilities

-PMT trip
It sees voltage at T2 causing it to believe that the "1A"contactor is welded, a directional contactor is welded , or 1 Rec is shorted.

Just measure from (Batt -) to (T2) .
they are both under the silver tag on the card that identifies their location.

You will detect a voltage because of frame capacitance but it should be greater than 15% and less than 85% of battery voltage, if it isnt the card will not send a signal via terminal R3 to turn the driver for the directional contactor on ( its the small black box with 4 screw terminals)

-SRO trip.
The card needs to see the vehicle in "neutral" before it will close a contactor

No directional input, no brake switches open and the throttle at zero.

-Bad oscillator card.

-The driver (small black box with 4 terms) is bad.

- Bad wiring harness.

But my money is the terminals in the back of the oscillator card have corroded.
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Running this thing probably costs you more than using a well designed update controller.
I have GE EV-1 controller from 1969. Works fine.

I don't think it even has electrolytic capacitors.

Semiconductors only being rated for 20 years.... come on man. 20 years ago was 1998. Yeah a few devices are going to go bad over time, but, it's not a plague (except for the capacitor plague, devices from early 2000s infamously fail due to attempted trade secret theft and counterfeit electrolyte failing).

It would certainly be easier to spend $100 on a little golf kart controller and be done with it, but, he's not condemned to failure just because he's using an old controller.

After 20 years every semiconductor device becomes a lottery, the percentage of failures starts to climb slowly and increasingly, it's the chemical breakdown of the metalised layers used in production of integrated circuits/diodes/thyristors(EV1) etc. Your driving an ev on the road and I would not want anyone to have a random failure whilst driving which could be avoided just by having a new dc controller. Granted the EV1 is a bit stylish - but leave it for the mantelpiece not the highway.:eek:
Running this thing probably costs you more than using a well designed update controller.
I actually have a running EV1B in the shop right now

A Clark EC500-25 made specially for Sears

It was built in 1972 ,and the electrics are good , it's the mast thats worn out.

We are actually debating repaing the mast trunions and using it as a "Shop Truck" because it is so easy and cheap to keep running.

The only reason the OP is having trouble is that they stopped teaching high current DC in school because it isn't used anymore.

I had a two year "Idustrial Electronics" degree , and 7 years working on electronics in the Navy before I started working for my father and it was a STEEP learning curve.

I went from trouble shooting everything from static exciters for 1.75 MW Generators , 20 ton electric winches , The ships telecommunication systems ,Flight deck lighting systems, 360 ton Air Conditioner systems ( With PLC's ) and the ice maker in the Officers Mess.

Then I got out , sat down with a Clark TM-15 ( EV-100 controller ) and was completely mystified.
I could identify the components and test them individualy but using a transformer on a DC system to catch the current spike to the motor and use that to charge a capacitor so it could then be used to reverse bias the SCR to turn it back off,( and rated for 1000 amp) and the act of charging the capacitor reverse biases the SCR you used to connect the capacitor to the main SCR.... I knew what PWM was , but I never saw anything like that before.

I know what ptandjb is going through.
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FSIP.biz sells rebuilt cards to fix this problem
(they also have the tech manual for it as a FREE down load).
To the OP. I've found FSIP to be a great resource. They have a forum there as well so you might want to post your questions there also and see what they say, but the suggestions made already are good ones. As for this old tech vs new controllers, these old controllers may be crude and bulky, but they have stood the test of time and many are still working fine. Parts and tech support are easily available as well. That can't be said for most of the new high tech EV controllers most guys on here are using.
I am intimidated by the difficulty of all this. Tomorrow will discuss options with my uncle at a family gathering. I expect he will repeat that if a new controller is required he will purchase one, that this expense pales in respect to his decades old dream to drive this car.


Called FSIP tech support who said they do not sell parts for this controller, only offer a re-manufacturing option. They declined to give me a cost and lead time estimate even though I read him specific information from the original invoice and spec sheet, saying he needed actual part numbers from the actual unit.


We will try one last time to see if it will send power to the motor using a test procedure I am now writing. If that fails will try some limited troubleshooting based on tests suggested in the manual and here. If results are inconclusive again or I prove unit defective, I see no other choice but to remove the unit. Is it possible to bench test the unit out of the car?



I will want to know if I find defective components, where can I find replacements since FSIP said they do not sell them? Are there any other options for repair other than shipping the entire unit back to FSIP?
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I could identify the components and test them individualy but using a transformer on a DC system to catch the current spike to the motor and use that to charge a capacitor so it could then be used to reverse bias the SCR to turn it back off,( and rated for 1000 amp) and the act of charging the capacitor reverse biases the SCR you used to connect the capacitor to the main SCR.... I knew what PWM was , but I never saw anything like that before.
That explanation succinctly summarizes what ten hours of reading and asking questions couldn't for me.

I finally get it now.
I am intimidated by the difficulty of all this.

Called FSIP tech support who said they do not sell parts for this controller, only offer a re-manufacturing option. They declined to give me a cost and lead time estimate even though I read him specific information from the original invoice and spec sheet, saying he needed actual part numbers from the actual unit.

I will want to know if I find defective components, where can I find replacements since FSIP said they do not sell them? Are there any other options for repair other than shipping the entire unit back to FSIP?
Sorry to hear they weren't more help. It may be because the controller was a version built for EV use and not a forklift application. What is the voltage of the car? At least you still have a last resort option of sending it to them.
Two parallel rows of 5 12v batteries. Talked again with Flight Systems tech support, they recommended re-manufacture even if they bench test the unit good if we wanted reliable operation. If unit is too old to support re-manufacture by them they guaranteed they would have a re-manufactured unit that would work. My uncle is tired if waiting, cost is not a concern anymore, time is. One of his daughters cornered me and said, all he wants in life is to drive this car once around the block before he dies. So tomorrow me and my cousin will visit my indestructible ageless uncle at work, do another test run through then out the unit comes if it fails to run again and i will get Flight Systems on the phone.


Pic below of uncle yesterday with a granddaughter and one of his 18 and counting great-grandchildren. Yes, he would fit right in with ZZ Top.


http://ptandjb.com/eddiesEV1/uncle0791.JPG
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There are some very, very simple 36 and 48v golf cart controllers for $100-$300. My Curtis controller would do that.

Generally closer to the $100.

I'd go with one of those.

Literally just add the keyswitch, a potbox for speed, and strap the battery and the motor to it. Done and done.

Probably won't do highway speeds, but, neither will the old forklift controller.
Two parallel rows of 5 12v batteries. Talked again with Flight Systems tech support, they recommended re-manufacture even if they bench test the unit good if we wanted reliable operation. If unit is too old to support re-manufacture by them they guaranteed they would have a re-manufactured unit that would work. My uncle is tired if waiting, cost is not a concern anymore, time is. One of his daughters cornered me and said, all he wants in life is to drive this car once around the block before he dies. So tomorrow me and my cousin will visit my indestructible ageless uncle at work, do another test run through then out the unit comes if it fails to run again and i will get Flight Systems on the phone.


Pic below of uncle yesterday with a granddaughter and one of his 18 and counting great-grandchildren. Yes, he would fit right in with ZZ Top.


http://ptandjb.com/eddiesEV1/uncle0791.JPG

Yeah the issue is the voltage , if it was 24, 36, or 48v they have them sitting on the shelf for exchange.
To All,

I am reposting from last year asking for any available advice as me and my cousin continue to try to help get my uncle’s EV project started in 1984 to a successful conclusion.

I am still trying to help my uncle realize his main bucket list item while there is still time. He has been working off and on for over 30 years to slowly build an electric car. When he attempted to power it for the first time last year the controller failed to trigger the contactors to send power to the motor. He said all he wants to do is to drive this car at least once before he dies. He gets up every day and puts on his union machinist suit and goes to work in a construction company warehouse in Ludlow Massachusetts doing maintenance and machinery repair. He has started talking about retiring and would then need to find another location for the EV project car if it is not yet finished. So I was asked to come take a look. In my distant past I have a degree in electrical engineering and have experience with SCR controlled injection molding machines so theoretically I should technically understand all documentation and pretty much understand how things should work.


The car chassis was hand built:

http://ptandjb.com/eddiesEV1/carfront0491.JPG

http://ptandjb.com/eddiesEV1/carside0490.JPG

Overview of controller assembly:

http://ptandjb.com/eddiesEV1/EV1fullview0483.JPG

http://ptandjb.com/eddiesEV1/EV1closeup0485.JPG


I had thought last year we had proven that the EV1-B controller was defective and went back last month to try to disassemble and test the controller. We repeated our original investigation, with SEAT and BRAKE switches bypassed and KEY, FWD, and ACCEL switches appropriately set there was no contactor activation. Looking more carefully at the documentation, I realized that I had not considered STATIC RETURN TO OFF and PULSE MONITOR TRIP requirements, and could no longer conclude I had proven the controller defective. I was confused as the exact process (see confusing manual excerpts below). Because I was not up to speed on these requirements, we called it a day and I came home to study documentation and try to figure out a way forward. An initial successful outcome would be sending power to the motors in forward or reverse in START ACCELERATION mode.

From the manuals:

The control circuit is energized by closing the Key switch, Seat switch, and moving the Forward or Reverse lever to either position and then depressing the accelerator, thus closing the Start switch. This applies power to the control card and, if the ”static return to OFF” requirement and the pulse monitor trip requirement are satisfied, turns on the PMT driver, which will close the selected directional contactor, completing the circuit to the traction motor. The directional contactor is controlled by the directional switch.
· STATIC RETURN TO OFF — this built-in feature of the control requires the operator to return the directional lever to NEUTRAL anytime he leaves the vehicle and returns. If the Seat switch or Key switch is opened, the control will shut off and cannot be restarted until the Directional switch is returned to NEUTRAL. A time delay (0.5 seconds) is built into the Seat switch input to allow momentary opening of the Seat switch. This same delay requires the Directional switch not be closed until both the Key switch and the Seat switch have been closed for 0.5 seconds.
· PULSE MONITOR TRIP — this function contains three features: The look ahead, the look again, and the automatic look again reset.
If 1 REC (the main SCR) is shorted or lA is welded. PMT will look ahead and prevent F or R from closing if either condition exists.
If 1 REC fails to commutate, or if lA power tips remain closed when they should be open, the control will open F or R contactor. PMT will then look again by testing for a fault and, if none, reclose F or R. If the fault still exists, the F or R will reopen and remain open.
If lA closes before a second commutation failure, the look again counter will automatically reset. This eliminates the inconvenience of resetting the PMT with the key switch if the tripping is due to random noise.
When the PMT circuit prevents F or R from closing, the PMT circuit can be reset only by opening the Key switch.

I have uploaded various relevant files from various sources to my web domain in directory where they can be viewed or downloaded:

http://ptandjb.com/eddiesEV1

EV-1 Spec1.jpeg 1st page original EV-1 controller spec sheet
EV-1 Spec2.jpeg 2nd page original EV-1 controller spec sheet
EV1.pdf EV-1B Troubleshooting Manual & Parts Lists
EV1WireDiagram2.docx EV-1B Wiring Diagram as Word Document
EV1WireDiagram2pdf.pdf EV-1B Wiring Diagram as PDF Document
EV1closeup0485.JPG EV-1B close-up view
EV1fullview0483.JPG EV-1B full view
carfront0491.JPG front view car chassis
carside0490.JPG side view car chassis
ev1maint1.pdf GE EV-1 Troubleshooting/Repair Manual part 1
ev1maint2.pdf GE EV-1 Troubleshooting/Repair Manual part 2
ge_ev1_rs_notes.pdf Roger Stockton’s EV-1 SCR DC Motor Notes
ge_ev1_rs_notes.docx Roger Stockton’s EV-1 SCR Notes (edited)


Before our next trip to Ludlow to further evaluate the EV1-B, I have some questions:

Is there anyone familiar with the GE EV1-B controller willing to talk to me on the phone and/or correspond by email and/or make a visit to see the car to render technical assistance? All reasonable expenses would be covered. Also Facetime video call assistance is an option.

Is there a way satisfy/bypass/eliminate the PMT requirement to rule that out as a problem? I have trouble figuring how to understand its function.

If we prove a failure of the EV1-B controller does anyone have experience working on this unit?

If demonstrated defective, are there repair options available sufficiently local to Ludlow Massachusetts that can visit the site or are there sites we can bring or ship the EV1-B controller? A typical forklift repair technician may simply want to replace the EV1-B unit and not troubleshoot faults inside the unit.

Is there a source for spare parts/technical support for the EV1-B controller if we get inside the box?

Thanks in advance for help, if fortunate to succeed there will be a YouTube video of a successful outcome. This email will be cross posted at diyelectriccar.com and evdl.org.

Paul Traceski

I hope you read this even though it is an old thread , but I blew up your controller picture to see if I could check the wiring connections and....

...your 1A contactor is welded.

It's the large relay/contactor in the bottom right of the picture.

The controller will not close a directional contactor until it sees that thing open.( It's failing the "Look Ahead Test")
Decided to send the 35 year old EV1-B unit back to FSIP for diagnostics. Bench tested, the unit had multiple failures. Uncle opted for full remanufacture at cost of $579. Installed remanufactured unit in car, did a bit more wiring work to fully implement the design, then successfully ran the jacked up car in forward and reverse by hand operating the FSIP Model 800 Accelerator mounted on a switch board mockup. Now we move forward on to other issues.
A few pictures:
It was dark starting work so my uncle lifted my cousin to the ceiling to replace burnt out lights:
http://ptandjb.com/eddiesEV1/lightschange0842.JPG
We were working on filling the brake cylinder and lines with fluid, uncle is working the brake pedal while cousin trying unsuccessfully to get brake fluid down the lines. Eventually discovered the 35 year old brake lines were blocked by corrosion, so all are being replaced.
http://ptandjb.com/eddiesEV1/brakeline0900.JPG
Our biggest current issue as we move switching controls to the driver position is figuring out how to integrate the E30-M800-001 FSIP Model 800 Accelerator into the car. While it is 35 years old it appears to work just fine, I guess it is probably comparable to current FSIP Model 810.
http://ptandjb.com/eddiesEV1/accelSW0847.JPG
The FSIP Model 800 Accelerator has two switches and a trimpot. The spring loaded accelerator arm so far we pushed manually by hand in testing the wiring and motor. As shown the top of the arm is moved from right to left. As the arm movement begins the ACCEL START switch is closed. As the arm moves left the trimpot send command for increased speed. We did not bottom out the arm to make the 1A BYPASS switch with the wheels turning for fear of excessive speed with the wheels jacked up. That function will be tested later.
My uncle machined a provisional floor accelerator pedal which he shows below the now disconnected Model 800 Accelerator. Here we are stuck. How do we integrate this accelerator with a foot operated pedal? We do not have a clue. My uncle who previously owned a machine shop for decades can build anything.
Also will consider other recommendations for implementing the accelerator function. While my uncle has been mentioning retiring now and then he said finishing and driving the car first is a requirement.
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It looks like there could be many ways to connect the machined accelerator pedal to the electronic control unit:
HTML:
<IMG src="http://ptandjb.com/eddiesEV1/accelSW0847.JPG" width="800"></IMG>


Simplest might be a cable as used in bicycles, motorcycles, tractors, lawn mowers, and cars. You will need to rig some linkage to adapt the range of motion of the pedal to that of the control, and add springs to return the position to minimum when released. Can you post a short video showing the action of the motor as the accelerator is positioned? Seems like you are 95% there. :)

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I don't know your space constraints, but looks like you could rotate the control so the lever moves vertically and attach a link from the lever to the front of the pedal.

I finally just looked at the pictures of his car. I didn't realize it was a Trimagnum build. Very cool! I've wished I could do one of those for decades.
Much progress has been made, car and controller are largely operational, previous problems solved. One big issue with the ammeter gauge was solved by running independent power, ground, and signal wires directly from the 500 amp shunt. Much of car infrastructure outside the fiberglass body had to be replaced as stuff goes bad sitting for decades. 86 year old uncle may be forced to retire at years end because the construction company he works for is being sold, so we are working expeditiously to full completion and a few issues are currently outstanding. My last three or so emails/technical support calls to Flight Systems Industrial Products have gone unanswered so I will post my questions here.


I made a few short videos. The first is uncle testing the car horn:


http://ptandjb.com/eddiesEV1/horn0941.MOV

The second is a view of dashboard under construction and a view of engine compartment.


http://ptandjb.com/eddiesEV1/intro0940.MOV


The third is a test of the controller and motor contactors. The car has tires but is up on blocks so the tires can spin freely. The plan was to press the accelerator to activate the Start switch and then before the motor had time to spin the tires up to unsafe speeds press the accelerator to make the Bypass switch for full function test. This was done in forward and reverse.

http://ptandjb.com/eddiesEV1/motor0943.MOV



The first question we have does the sound of the motor and differential sound OK, does anyone hear an issue?


The second question is really big, in that it appears that the wiring to the motor is reversed in that putting the car in forward with positive input to L9, the wheels spin in reverse, and putting the car in reverse with positive input to L10, the wheels spin forward. Uncle and cousin are hoping against hope that this will change when we get the car off blocks and trailer for parking lot test runs, but I doubt it. Swapping the wiring on the motor would be messy, uncle wants to know if we can simply relabel the forward/reverse switch, does it matter, is there an intrinsic difference in the controller between forward and reverse functions of the EV-1B controller?
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It works!

If it's just a series DC motor (I think it is), you can switch the direction it rotates by just moving 2 motor wires, shouldn't have an impact otherwise.

The motor has 4 terminals. The start and end of 2 different coils. One coil is the rotating part of the motor, the other coil is the stationary part of the motor.

All you have to do, is pick ONE pair of those wires, and swap them. Not both pairs, just one pair. Doesn't matter which pair. Doesn't matter which is positive or negative. Whatever they are, just have them trade places.

You could do this at the motor, or, at the controller, shouldn't matter. But only swap cables that go to the motor. If there are other wires on the same terminal (like if you have a big stack of Negative wires), leave those alone. So it's easier to not screw it up by just changing them at the motor.
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