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Discussion Starter · #1 ·
First yes I made a series of silly mistakes.. Now could those experienced guys here give me your thoughts if the controller is dead or maybe I just fried the precharge or just fried the 12v input?

First mistake I fed 24v into 12v input... did I fry it then? Then had wires wrong way around on ac motor..Did that cause my precharge resistors to be fried? Lastly I am not sure but maybe I had polarity on drive battery incorrect I was not using rated 144v just a chunk of Chevy Volt batteries about 48v. After 1 or 2 minutes with all the above the external precharge resistors smoked and burn out. They went from the positive input wire via a manual switch i left on. When I saw the smoke I disconnected everything. After all this the acc test wire had come away from the factory crimp plug. Its a Chinese 144v Ac controller with a chinese 144v motor. At no time did the precharge relay click. I am going to test again with a light bulb in place of resistors. 12v input and correct 144v drive battery. If its still dead I guess I broke it. I totally dont have the money for a new controller. I opened it and there was no physical damage to be seen. No bad smell no residue under lid. Please give me your thoughts. No unpleasant comments please. Thank you.
 

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Hi
I don't use a pre-charge relay - I have an old kettle element that I use as a pre-charge resistor - when the voltage gets up there I switch the main contactor

I suggest you wire it all up carefully - use a manual pre-charge if you have cooked the resistor

And see what happens!

With my controller voltage does not matter but I know with some controllers they will sense the voltage and refuse to play if it's too low
 

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Discussion Starter · #4 ·
I couldn't find out what the resistors were as they were blackened. I decided to replace them with two 47ohm resistors wired in parellel. I added two diodes wired in parallel so that no reverse polarity can occur via the precharge wire at least. Thinking now a fuse for the precharge wire might be a worth while idea too.

The controller now works fine. 🙂
 
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