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power factor unbalanced? 1

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mag100

Industrial
Sep 24, 2001
11
US
We had a contractor put a fluke power quality analizer meter on our main switchgear. The info they recorded was that phase A on our three phase 480volt delta wye system was reading a power factor of 50% lagging and the other phases were reading phase B 80% and phase C 98% lagging. We have a square D switchgear with a meter on the gear that reads the power factor per phase plus voltage current KVA KV THD and so forth.. The readings on that meter read balanced with 80% power factor per phase A B and C. did the math for KV and KVA of the reading and all worked out to the display of PF.
We have no info from the contractor of KV or KVA of the phases. the question at hand is can his meter be correct? How can prove what meter is reading correctly. when i do the math using the meter installed on the switch gear it all works out. just need some advice to prove what we have and move on.
 
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Unless you have a very unusual load, I would say he hooked up his meter incorrectly. Both phasing and polarity must be correct or else the readings can get pretty odd. So pretty much everything he read off the meter related to power or power factor is probably garbage.

David Castor
 
thanks, if there is any more info needed let me know!!
 
I agree with dpc. Improper polarity on the connections is probably the cause.
 
I support dpc on this. Many contractors would recognize these readings as improbable and recheck their connections while still onsite. The readings on the panel meters are a reality check that your contractor may have ignored.

Bill
--------------------
"Why not the best?"
Jimmy Carter
 
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