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LOAD CALCS WITH OPEN DELTA?

LOAD CALCS WITH OPEN DELTA?

LOAD CALCS WITH OPEN DELTA?

(OP)
I have a real basic question.  I'm in the utility industry, and mainly have dealt with 3phs 120/208, 3phs 277/480, or 1phs 120/240.  Well now I'm dealing with open delta.  I received load calcs from a new customer.  Not believing their load summary, I'm attempting to pull out/calculate the customer's 3phs load vs. their 1phs load from their panel schedules.  My issue is with figuring out the total 3phs amps.  For example if I have an AC unit drawing 1500VA on A phase (secondary) and 1500VA on B phase would the calculation for connected amps be:

[1500VA*2]/[240V*sqrt(3)] = 7.2A?

Any feedback would be great.

RE: LOAD CALCS WITH OPEN DELTA?

"For example if I have an AC unit drawing 1500VA on A phase (secondary) and 1500VA on B phase would the calculation for connected amps be:[1500VA*2]/[240V*sqrt(3)] = 7.2A?"

If the load is only on Phase A and B that is a single phase load. Drop the 1.73 in the caculations. If the load is 3 phase the load is on Phase A,B and C.
[1500va x 3]/240x1.73= 10.8A.

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