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Old 04-30-2009, 05:14 PM   #1103 (permalink)
MPaulHolmes
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Join Date: Feb 2008
Location: Maricopa, AZ (sort of. Actually outside of town)
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Michael's Electric Beetle - '71 Volkswagen Superbeetle 500000
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You are right. It didn't make sense. I found out the problem, though! Half way through the power section, I changed my mind about which bus bar would be B- and which would be B+. I thought everything was fine, but I had already soldered on the capacitors assuming the other way, and did the mosfets/diodes assuming the new B- B+ orientation. Oops. Basically, I had a NEAR short circuit through 10 beefcake diodes from M- (which is connected to B+ through the motor) to ground. So... I had about 50 amps going through the pre-charge resistor for about 3 seconds. No problem for the diodes, but a problem for the pre-charge resistor.

I just unsoldered all the capacitors, and now I'm going to reverse all of them, put in NEW DANG DANG DANG resistors from gate to source and drive into the sunset! ANGER!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!1 STUPID IDIOT!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
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