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Hi Sebart
I am a mechanical guy - so the OpenRevolt controller is the first complex electronic device I have made
Anyway
I built the controller expecting to get it on the car in a couple of weeks -
over a year later the car was completed,
during that year my controller was in a dusty workshop used for woodwork as well as my car
When I energized it for the first time there was a pop and and some smoke -
I tested it and it still worked so the car was driven on it's test drives (I decided that I had zapped a passing spider)
A couple of weeks later
I then checked the isolation to the chassis - OOPS - took the controller off and found a blown MOSFET
I replaced two MOSFETS - everything was good - chassis was isolated, car went well
Later when I switched on the pre-charge - my pre-charge light didn't go off - stayed lit
I stupidly energized the contactor and the car lurched as it blew a number of MOSFETS and one of my battery terminals
My "diagnosis"
The first failure was caused by either dust/spiders or possibly a gate resistor not properly soldered
The second failure was caused by - damage from the first failure
or possibly what I was doing with the pre-charge
I was pre-charging with a halogen bulb - that is OK
BUT I was also discharging the capacitors every time I shut the car down by disconnecting the battery and driving the car forwards using the capacitors
The car would lurch forwards a couple of inches
Reading the thread Paul also did some damage discharging capacitors this way
Another possible reason for the failure
the original MOSFETS were IRFP4668 with a second line saying RO41P
The two replacement MOSFETS were IRFP4668 with a second line saying R137P
Don't know if that would make any difference but different batches may react differently and not share well
I have now built a new power board - all new diodes and MOSFETS - re-using the capacitors
Using the standard OpenRevolt parts
I am waiting for the new gate resistors
I do have the new MOSFET driver but I was awaiting advice as I find that I can build a circuit - but rebuilding seems to require a higher skill set
I am still looking to build a more powerful controller as I am using my car for some motorsport and more is always better - but I have decided to wait until the experts on this forum complete their development and then buy the new kit
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