So much for the safety check!

Damn.  I should NOT make important electrical connections after work, when I'm tired and there's not enough light.

I had reversed polarity at the controller box.  A simple, stupid, crucial error.

I turned the key on the 12V circuit, the contactor closed the 72V circuit, and promptly welded itself closed.  The 400 amp fuse burst into flame.

Turning off the key didn't stop this horror-show, because of the stuck contactor.  I hit it with the fire extinguisher, and by then the fuse had finally vaporized. 

This tells me I ALSO need some kind of a manual disconnect, to break this circuit, in case of faeco-ventilatory intersection.


I felt for sure I had also toasted the $750. controller.  I felt like crying.  What a dumb thing to do!  "+" and "-" are IMPORTANT SYMBOLS!

After a few minutes of cussing and smoking, I calmed down long enough to call the tech guys to see how to test my controller.  It turns out I got lucky...the fuse protected it from my error.

Now I just am out another $40 for a new fuse and time waiting for it to ship out.

I did make a mount to keep the motor from jumping around, so the day isn't completely shot to hell.