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3 Phase electric power and load calculation

3 Phase electric power and load calculation

3 Phase electric power and load calculation

(OP)
hi....
i want to know the formula for calculation of 3 phase load(kva) in real life.i have current load values on 3 phases which are different as 56amp,42amp,40amp. Voltage line to neutral is 220v and line to line is 380v.do i use 3 or root(3) or nothing in the formula.how can i calculate load on one phase and total load on all the three pahses in 3 phase system

RE: 3 Phase electric power and load calculation

It's probably easiest to multiply the line current and the line to neutral voltage. So 56 A * .22 kV = 12.32 kVA. Repeat for the other 2 phases.

RE: 3 Phase electric power and load calculation

Three phase load:

For a balanced wye connected
load only:

P = 1.732 x VL x IL

in your case the load is not balanced so do the loads individually and add them up like magoo2 suggested.

56A x .22kv (phase A) + 42A x .22kv (phase B)+ 40A x .22kv (phase C)


If the load was balanced and the line current for example was 50A

P = 1.732 X 50A X .38kv

RE: 3 Phase electric power and load calculation

your total kVA in this case is 30.36

"Throughout space there is energy. Is this energy static or kinetic! If static our hopes are in vain; if kinetic — and this we know it is, for certain — then it is a mere question of time when men will succeed in attaching their machinery to the very wheelwork of nature". – Nikola Tesla

RE: 3 Phase electric power and load calculation

Quote:


P = 1.732 x VL x IL

OK, if we're going to pass out equations, let's try to be accurate. If P = Power, you forgot to account for the power factor. I have enough aggravation with non-EEs on this.

RE: 3 Phase electric power and load calculation

Quote:

If P = Power,
Well, he/she asked for kVA...so the equation still holds but with wrong term; "P" should be changed to "S".

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