# Another capacitor bank issue



## Captain Voltage (Dec 16, 2015)

We have an ABB auto cap bank. ten 75kva 480vac 3ph.
Number one cap kept blowing 125a fuses on phase A. I replaced the cap with new. Kept blowing fuse. Contactors contacts welded themselves closed. I replaced the contactor new, I replaced the cap new again. Still the fuse blows on A phase. The capacitors draw 68ish amps at best and is blowing 125a fuse. Whats going on there?


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## frenchelectrican (Mar 15, 2007)

Sound like you got a shorted caapaiiitor by either voltage or current shifting ..

Did you test that bank to make sure it is ok ??


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## Captain Voltage (Dec 16, 2015)

Just the one capacitor out of ten is blowing the A phase fuse. The thing is this is the third time I have replaced the #1 cap,,, same results. The controller is working fine as is the other nine caps.


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## frenchelectrican (Mar 15, 2007)

Ok did you ever try to have voltage reading ?, i am thinking that a loose connection somewhere along on A phase even the POCO transformer is little off balanced.. 


You should get ths voltage recorder and log it so you can see the spike or sag show up..


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