Thanks for the advice. I wasn't around, but I think the robot was turned on again after the breaker tripped... Whoops! And as far as fixing the problem of wiring things backwards, well I agree that the best solution is to double check to avoid stupidity
The PDP does output power but the status lights don't seem to function... We can play around with the components a bit but we've replaced them with the spare set we kept on last year's robot for the time being.
If the VRM is reverse polarity protected, any thoughts on why it doesn't work now? And also ideas on why the PDP functions partly?