The MOSFET's are available, http://www.mouser.com/ProductDetail/Infineon-Technologies/BUZ30A-H/?qs=sGAEpiMZZMuJc9I8Ed1ELHOeD%252bVaTg6h
The hardest part to get is the freewheel diode, MR2406FR. The problem with this part is that the anode and cathode are backwards compared to most available parts. I did a quick search and could not find any at the usual vendors. You can find the MR2406FR diodes however, http://www.diotec-usa.com/MR2400FR.pdf But I couldn't find anybody that sells them (without doing a more extensive search). Like Lee said, typically the gate resistor blows open (look for the through hole resistor that is connected to pin 1 of the BUZ30A MOSFET). I think it should read about 220 ohms (or depending on the design a low ohm value less than 330 ohms and not a short circuit). Good luck on your venture, it will be a learning experience! P.S. Also measure between pin 1 and 3 of the BUZ30A, that is gate to source. Sometimes the zener protection diode on the gate can short, it should be a 18V zener, like a 1n4746A, http://www.digikey.com/product-detail/en/1N4746A,113/568-4855-1-ND/2122184 Rod ----- Original Message ---- From: Lee Hart <[email protected]> To: Electric Vehicle Discussion List <[email protected]> Sent: Sun, January 20, 2013 7:33:32 PM Subject: Re: [EVDL] Curtis Controller Popped On 1/20/2013 4:10 PM, Danpatgal wrote: > Thanks Lee ... so how does one evaluate the gate driver circuit, and if it is > bad, replace it? > > I feel like I'm peeling back the layers of the onion ... and if I ultimately > can't do it, I'd have been better off having someone else repair it or > getting a new one. The control board is the small one with all the parts on it. You can power it separately with a small bench supply, and watch its gate output to be sure is is switching high/low properly. The big power board just has series resistors going from the gate driver to each of the MOSFETs. When a MOSFET dies, it can fail with a short from gate to drain. That puts pack voltage on the gate driver! With luck, the gate driver resistor explodes like a fuse, and 'saves' the control board. But sometimes, the gate driver resistors don't open until too late to save the gate driver circuit on the control board. -- A designer knows he has achieved perfection not when there is nothing left to add, but when there is nothing left to take away. -- Antoine de Saint Exupery -- Lee A. Hart, http://www.sunrise-ev.com/LeesEVs.htm _______________________________________________ UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub http://lists.evdl.org/listinfo.cgi/ev-evdl.org For EV drag racing discussion, please use NEDRA (http://groups.yahoo.com/group/NEDRA) _______________________________________________ UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub http://lists.evdl.org/listinfo.cgi/ev-evdl.org For EV drag racing discussion, please use NEDRA (http://groups.yahoo.com/group/NEDRA)
