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#127929 - 03/19/02 07:51 AM 3 phase total amps
aldav53 Offline

Registered: 08/22/01
Posts: 547
Loc: Chandler, AZ USA
When measuring 3phase feeders with an amp clamp on a 100a panel, I believe each phase is good to 100 amps, but we do not add all 3 phases to have a total of 300 amps, correct?
The Golden Rule - "The man with the gold makes the rule"

#127930 - 03/19/02 11:38 AM Re: 3 phase total amps
Bob Offline

Registered: 02/05/02
Posts: 182
Loc: Mobile, AL, USA
You are correct. The panel is rated 100 amp
3 phase. Each phase is limited by the breaker and the conductor rating. As an example you might measure A = 50a B = 60a
and C = 50a. You do not add the total and
get 110 amps.

#127931 - 03/19/02 04:30 PM Re: 3 phase total amps
Ron Offline

Registered: 03/13/02
Posts: 577
Loc: White Plains, NY
If you were to measure 80 amps per phase, it would be 80 ampere, 3 phase on a 100 ampere panel. And, the utility will charge you for the equivelent of 80 amperes, 3 phase which is more than 80 amperes 1 phase.


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