View Single Post
Old 03-30-2012, 09:19 PM   #18 (permalink)
MPaulHolmes's Avatar
Join Date: Feb 2008
Location: Maricopa, AZ (sort of. Actually outside of town)
Posts: 3,832

Michael's Electric Beetle - '71 Volkswagen Superbeetle 500000
Thanks: 1,368
Thanked 1,119 Times in 734 Posts
Those are all good suggestions. The software takes care of some of the issues:

Infinite resistance (a cut throttle) would flag a fault in the software. The pwm would be disabled. If the current sensor output suddenly lost power, the microcontroller would set the pwm to zero in about 0.000025 seconds also.

I expected the contactor coil diode to be included if the person wanted to, but right at the contactor. The EV200 with the economizer recommends not having it, although I used a diode right at my ev200 contactor and it didn't seem to affect operation. I agree that it wouldn't be a bad idea to have a spot for a diode, and leave it up to people to put it in or not. I've just heard that it's best to have the diode right next to the contactor, so the voltage spike never makes it to the control board at all.

I think you are right about the output of the 7805. I haven't heard of a small choke for Vcc. It sounds like a good idea though.

Edit: I was reading today about MLCC caps, and they have some really cheap 10uF MLCCs that I think could replace both the 0.1uF and 10uF Aluminum cap.
kits and boards

Last edited by MPaulHolmes; 03-30-2012 at 10:32 PM..
  Reply With Quote