Transformer Formula

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bhsrnd

bhsrnd

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Fort Worth, TX
If I have two 150kVA 480-208Y/120 transformers which formula(s) would I use to determine the load on the primary if I know what the secondary load is and vice-versa?

The loads are balanced on the secondary and serve computer equipment. There are no motor loads on the secondary. The primary is fed with a PF of .9 from a UPS module. Also, to complicate the matter, one transformer has a phase angle of 30 and the other has a phase angle of zero. How do the former and latter affect the formula(s)?

A thread from 2006 discussed something like this but the thread discussion became overly confusing and so I'm posting this one.
 
Calculate the secondary kva. Use that kva for the primary. The primary kva is the same as the secondary kva, almost. There are some losses but we usually ignore them when making this calculation. Can you make this calculation?
 
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Yup and it came out fairly close. Does phase angle not play any kind of role in this simple approach or is that a bigger can of worms?
 
bhsrnd said:
Yup and it came out fairly close. Does phase angle not play any kind of role in this simple approach or is that a bigger can of worms?
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Phase angle does not play any part in this caculation.
 
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