Quote:
Originally Posted by princeton
It sounds like the margin of error might be getting a bit slim if using 200V mosfets with 144 battery voltage. 144V + 25 = 169 V. It's still 31 volt leeway to take into account an errant spike here and there, though. Does anybody know if there have been any problems with the 200v mosfets blowing?
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It's worse than that... fresh off the charger, my 144V nominal pack of floodies drop from ~178V to about 162V. They'll stay there for hours. However, one "advantage" with floodies is the heavy sag they experience under load. For my setup, a 2nd gear start will peg the motor amps at 500A and the battery amps at about 70A. That 70A from the batteries will drop the pack voltage about 7V. So, 155V + 25V = 180V peaks.
So, I think we can safely say that the controller will survive 500A output with an actual pack voltage of 155V for brief periods of time. Once the surface charge wears off, I typically run somewhere between 126V and 150V depending on current draw and state-of-charge.
I'm at 7k miles on the controller and just over a year with no problems with the power electronics. (i'll attribute the most recent problem a few pages ago to assembly procedures and structural hardware).