MV 4160v motor imbalance protection
MV 4160v motor imbalance protection
(OP)
I am in search of some form of conditioning/protection that may assist in cleaning up a voltage imbalance being incurred on a medium voltage 4160v motor starter. There is an additional load on the incoming power from downstream that is causing phase imbalance enough to vibrate and burn out motors for this compressor station. I plan to set PT's and a Fluke 434 power analyzer to record the imbalance and prove how bold it is. I plan a 1 week study, then I need to be able to make suggestions for remidying the issue. Any suggestions?






RE: MV 4160v motor imbalance protection
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If it is broken, fix it. If it isn't broken, I'll soon fix that.
RE: MV 4160v motor imbalance protection
RE: MV 4160v motor imbalance protection
RE: MV 4160v motor imbalance protection
I have new information. The original issue was resolved in a wiring problem, but there is one issue left. On occasion, there are rectifiers being shorted in the motor VFD. This is a Toshiba unit,900hp compressor, 4160v with a 1.15 SF. I found a recloser on site with the following being monitored. The incoming is 12,470v and I viewed ABC 7520v,7423v,7422v, seems A is a bit high? Also, my Power Factor was right at .76. KW on ABC was 256,267,254 with 782 total. What I have found out is that the utility is now admitting that there is capacitor switching occurring in a distribution yard close to this unit, coincidentally occurring close to the times of the rectifier loss. Even though that is very brief, would you not think this transient overvoltage could be occuring and taking out these rectifiers? A ringwave effect or even a surge charge? If so, do you think a harmonic filter or a TVSS might assist. Any thoughts appreciated, thanks for quick responses.