PDA

View Full Version : Wiring without a 12V aux battery?



__Tango
28 September 2010, 2152
hey there. While trying to draw up the electrical diagram for my bike, I got to thinking...how does this work when you don't have a 12V aux battery (e.g. running solely off of a DC/DC converter to provide the 12V)?

I'm attaching a reduced diagram of what i mean. When the ignition switch is closed, do you expect the contactor to engage?

423

I ask because it seems that even though the switch is closed, the contactor coil won't be energized because the traction pack loop isn't closed so therefore the DC/DC converter can't actually produce any 12V current.

Am i missing something here?

Thanks!

frodus
28 September 2010, 2257
that drawing shows the DC-DC converter energized. If you close the switch, it'l probably cause an explosion. You'd be shorting out the battery.

If you had a controller hooked up opposite side of the battery, on the left side, then it would work.


Your DC-DC converter and battery are one loop. The contactor/battery/controller are another loop.

Also, with that, the DC-DC converter is always "ON".

__Tango
28 September 2010, 2302
that drawing shows the DC-DC converter energized. If you close the switch, it'l probably cause an explosion. You'd be shorting out the battery.

If you had a controller hooked up opposite side of the battery, on the left side, then it would work.


Your DC-DC converter and battery are one loop. The contactor/battery/controller are another loop.

Oh...yeah, duh. Too much simplification from the original drawing.


Also, with that, the DC-DC converter is always "ON".

Right. i see that now. This is actually the information i was originally looking for.

Thanks!

frodus
28 September 2010, 2314
Np Bro.... hope it cleared it up.

BaldBruce
02 October 2010, 2246
459
Here's what I am doing to avoid using a battery.....SuperCap style:cool: