Difference Between KVA Explained
What does KVA Mean?
There are technical terms aplenty when it comes to generators, and they can be confusing if you are not familiar with them. A term you will see regularly in power generator specifications is kVA. This is essentially an indication of the power output. We explain in more detail below, with advice on what kVA rating you might need.
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Power Factor: a Measure of electrical efficiency
You can convert between kVA and kW if you know the efficiency of the electrical system.
Electrical efficiency is expressed as a Power Factor between 0 and 1: the closer the power factor is to 1, the more efficiently the kVA is being converted into useful kW. Generators have a power factor of 0.8.
Kilovolt-amp (kVA)
kVA is kilo-volt-ampere. kVA is a unit of apparent power, which is an electrical power unit.
1 KVA is equal to 1000VA:
1kVA = 1000VA
1 KVA is equal to 1000 times 1V times 1A:
1kVA = 1000 × 1V × 1A
kVA to volt-amps calculation
The apparent power S in volt-amps (VA) is equal to 1000 times the Apparent Power S in kilovolt-amps (kVA):
S(VA) = 1000 × S(kVA)
kVA to kW calculation
The Real Power P in kilowatts (kW) is equal to the apparent power S in kilovolt-amps (kVA), times the power factor PF:
P(kW) = S(kVA) × PF
kVA to watts calculation
The Real power P in watts (W) is equal to 1000 times the apparent power S in kilovolt-amps (kVA), times the power factor PF:
P(W) = 1000 × S(kVA) × PF
kVA to amps calculation
Single phase kVA to amps calculation formula
The current I in amps is equal to 1000 times the apparent power S in kilovolt-amps, divided by the voltage V in volts:
I(A) = 1000 × S(kVA) / V(V)
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3-phase kVA to amps calculation formula
Calculation with line-to-line voltage
The phase current I in amps (with balanced loads) is equal to 1000 times the apparent power S in kilovolt-amps, divided by the square root of 3 times the line-to-line RMS voltage VL-L in volts:
I(A) = 1000 × S(kVA) / (√3× VL-L(V) )
Calculation with line to neutral voltage
The phase current I in amps (with balanced loads) is equal to 1000 times the apparent power S in kilovolt-amps, divided by 3 times the line to neutral RMS voltage VL-N in volts:
I(A) = 1000 × S(kVA) / (3× VL-N(V) )
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