Wednesday, February 4, 2009

Schematic (Draft)

I've just about finalized my electrical schematic.

I'm using 2 contactors in the design. The first is triggered closed via the key switch and the second by the foot pedal. The second contactor has a precharge resistor across its leads. This way, when the key is turned to "on" and my foot is off the pedal, the controller will begin to precharge. When I apply pressure to the foot pedal, the second contactor closes, ending the precharge, and allowing electricity to flow freely to the controller. As long as I wait a few seconds before applying gas (as most drivers do anyways), then the controller should precharge sufficiently.

The precharge/contactor is also a safety feature - if the controller fails in the full throttle position, I can just instinctively lift my foot off the pedal and the second contactor will open. The huge demand of current will quickly fry the resistor and stop the car. If the second contactor fuses closed, then I can turn the key to off to open the first contactor. If first contactor fuses closed, then I can pull an emergency cable triggering the circuit breaker open. Of course if I'm fusing contactors left and right then I imagine my 400Amp fuse should have blown breaking the circuit as well. Whew! I'm not expecting the car to run away with me, but I think I've got enough safety measures in place just in case!


Mark Brems said...

Thank you. I am electrifying a Porsche 914, and this wiring schematic will be very helpful. In fact, I owned a Triumph GT-6+ for several years before I sold it a couple decades ago. I only wish I had that car to convert now. Here's my blog:

evaddict said...

Thank you so much for documenting your conversion like you did. I am converting the EXACT year car. This site is invaluable to me. See my conversion blog if you are interested. Careful, you may get deja vu!