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Under/Over voltage settings for 480 VAC gen-set

Under/Over voltage settings for 480 VAC gen-set

Under/Over voltage settings for 480 VAC gen-set

(OP)
What should the recomended settings be for over and under bus volatage relays on a genrator set operating at 480 VAC?

RE: Under/Over voltage settings for 480 VAC gen-set

It depends on the application.  If it is running in island mode, not connected to utility grid or other generators, and not service life-safety equipment, I'd suggest 110% and 90% with a suitable time delay or inverse time curve.  

RE: Under/Over voltage settings for 480 VAC gen-set

Irrespective of grid or isolated operation, set your relays to 115% and 85% inverse characteristics for O/V and U/V respectively. Check with your type of connected load for time setting.

RE: Under/Over voltage settings for 480 VAC gen-set

Suggestion: The emergency generators are usually not designed with over/under voltage protection since their intent is to function in spite of various load side adversities, to supply power to emergency loads.

RE: Under/Over voltage settings for 480 VAC gen-set

(OP)
This is an emergency lighting system that supplies emergency power for egress lighting loads on an offshore floating facility.I presently have it set at 110 % and 90% respectively.I was pretty sure I was close but wanted to get some feedback from other idustries.I do occassionally sync to my normal power which is three 4160 4750 KW genset's but only for 5 seconds.Anyway thanks for the feedback guys.

RE: Under/Over voltage settings for 480 VAC gen-set

TYBOY, ya goin' to the Christmas party in Lafayette this coming weekend?  Most attendees will check in at Hotel Acadiana

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