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Question

HELP!! POWER SUPPLY WONT TURN ON!!!

Mar 22, 2015 7:34AM PDT

Ok so i bought a coolmax zpg-1200 of ebay a couple days ago for home audio use and this is the second time ive done this, first power supply worked perfectly, still running strong, so i opened it up and connected all the yellow +12v rails together and connected all the black ground wires together from the board, i also connected the green psu on wire to a couple black grounds to turn the power supply on without a load but it doesnt seem to turn on, i flip the switch and the fan runs for a good 2 secs and then it shuts off. I connected my other power supply the exact same way and it worked no problem, what am i doing wrong??? Need help please!!

Discussion is locked

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Answer
No load is usually a shut off situation.
Mar 22, 2015 7:42AM PDT

You can over ride that with the method you noted but as presented the PSU sounds defective.

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diff black wires?
Mar 22, 2015 7:51AM PDT

There is multiple places where there is black wires and yellow wires coming out of the board, would it matter which wire i use or do all the same color represent the same denomination? There is a group of say 16 wires that say GND and there is a group of 3 black wires coming out that says GND1 and one black wire coming out saying SBGND, are they all the same ground or??

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I'd have to use an Ohm Meter to answer.
Mar 22, 2015 8:31AM PDT

But the "connected all the yellow +12v rails together" on second thought sounds bad. If this is a muti rail PSU it could detect you did that and shutdown.

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hmm
Mar 23, 2015 5:13AM PDT

Well as far as i know its a single rail +12v power supply that can output 100amps, thats the whole reason i bought it, the model is zpg-1200 coolmax i mean im really sure its a single rail...

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Link agrees.
Mar 23, 2015 5:21AM PDT
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Answer
Re:
May 7, 2015 5:18AM PDT

Although the PSU can be faulty but I won't recommend that you trust the colour coding of the wires as much as you do. If you have gotten it repaired, then trusting the colour coding is redundant since most repairmen don't care. Please note that you need to first establish that your CPU is working perfectly.