Practical tool · Energy
Power calculator: kW, kVA, A and W.
Obtain a useful order of magnitude for an initial load assessment. The result must be confirmed according to the equipment, their startups and operating conditions.
Indicative result
A load reading before a technical decision.
The calculation converts your input using the selected network and chosen power factor. It does not replace a study of inrush currents or load simultaneity.
Apparent power
125 kVA
Before reserve margin
Active power
100 kW
cos φ 0,8
Estimated current
180,4 A
400 V three-phase
Generator set to consider
150 kVA
Includes 20 % reserve
Why plan a reserve?
Inrush currents at startup, load simultaneity and operational changes can exceed the observed rated power. The reserve proposed here is a guideline, not a sizing validation.
W → kW
kW = W ÷ 1 000
kW → kVA
kVA = kW ÷ cos φ
kVA → kW
kW = kVA × cos φ
kVA → A
A = kVA × 1 000 ÷ (√3 × 400 V)
A → kVA
kVA = √3 × 400 V × A ÷ 1 000
Result with reserve
Recommended kVA = kVA × 1,20
MANOMAT Method
A calculation is a starting point, not a promise.
For a generator selection, MANOMAT examines the equipment to be powered, the start-up regime, the reserve, standards and site constraints.