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How can I calculate Kilowatt Hours from:

Complex Power = 1,5 kVA

Electrical current consumption = 10 A

It's three-phase electric power.

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  • \$\begingroup\$ look at myelectrical.com/notes/entryid/8/… \$\endgroup\$ – JIm Dearden Jun 10 '13 at 18:53
  • \$\begingroup\$ You need to know the power factor, the phase difference between voltage and current. Otherwise you cannot calculate Watt (hour). \$\endgroup\$ – jippie Jun 10 '13 at 19:10
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You can't. Knowing only the magnitude of the voltage and current does not tell you real power. To get that, you need the average of the instantaneous product of voltage and current. If both are sines, then power is the VA value times the cosine of the phase angle between voltage and current.

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If it's a 1kVA 3-phase system (500VA per phase) at a current of 10A, then the supply voltage is 50V. That is all that can be said. It tells you nothing about how much real power is being consumed.

I could add that I have never heard of a 3-phase supply voltage of 50V but that is irrelevant

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