[jackbauer]

ok did a few more tests on the "emergency shutdown" code I received from Paul. If the throttle is at zero and the lem sees 7 amps or over it shuts down and kills the contactor which is great. BUT. If the throttle is even slightly applied , the igbt fails short circuit and the throttle is brought back to zero , the controller continues to operate and the contactor stays closed.

On a slightly different matter I'd like some opinions on my motor. Prior to an energy show last week I had been running the shunt field at its full rated curent of 4 amps in order to limit max motor rpm to about 2k. I also had the controller battery current limit set at 200amps. On friday I fitted a slightly larger resistor to the shunt supply which reduced the current to about 3.3amps. I opened the controller to full power , selected 3rd and floored it. The battery current hit 420amps , within about 200 yards i was doing 40mph , scared witless and the motor was doing 3k and still pulling. I came off the power , stood on the brakes , abs cut in and my face got real up close and personal with the windscreen!

What i'm trying to find is an ideal middle of the road current to run the shunt field and also understand the relationship between the field currents , armature current , max motor rpm and motor power. Most info on the web about compound motors relates to industrial applications running at fixed voltage.