Make sense of your power requirements. Convert kVA, kW, amps and horsepower with live calculations for your generator project.
100 kVA · Three phase · 400 V
Your calculation will appear here.Electrical conversion only. Generator capacity also depends on starting loads and operating conditions.
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Use equipment nameplate values. Results are rounded for display.
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A useful generator sizing calculation starts with the equipment you need to run. Use this tool to put different ratings into comparable units, then bring the load information together for your project.
Planning backup power for a farm, workshop or commercial building? Our generator sizing and installation guide explains the next steps.
List the equipment that must operate and record each item’s voltage, phase, running power or current. Separate essential circuits from equipment that can remain off.
Identify motors, pumps, compressors and other demanding loads. Include the starting method and which items need to start together.
Tell us whether you need standby or prime power, the installation location, expected running hours and any planned expansion. Duty and site conditions affect the specification.
Share your load schedule with FW Power. We can discuss the generator, controls, fuel storage, delivery and installation and commissioning as one project.
| Convert | Single phase AC | Balanced three phase AC |
|---|---|---|
| kVA to Amps | kVA × 1,000 ÷ V | kVA × 1,000 ÷ (√3 × V) |
| Amps to kVA | I × V ÷ 1,000 | √3 × I × V ÷ 1,000 |
| Amps to kW | I × V × PF ÷ 1,000 | √3 × I × V × PF ÷ 1,000 |
| kW to Amps | kW × 1,000 ÷ (V × PF) | kW × 1,000 ÷ (√3 × V × PF) |
| kW to kVA | kW ÷ PF | |
| kVA to kW | kVA × PF | |
Three-phase V is line-to-line voltage; single-phase V is voltage across the load. √3 is approximately 1.732. For DC, kW = I × V ÷ 1,000 and I = kW × 1,000 ÷ V. AC equations use RMS quantities. See Schneider Electric’s apparent power and current guidance.
kW measures real power; kVA measures apparent power. Their ratio is power factor. A lower PF means more kVA is needed for the same electrical kW.
At 0.8 PF, a 60 kW load corresponds to 75 kVA. At 1.0 PF, the same 60 kW corresponds to 60 kVA.
The calculator starts with an example PF of 0.8 where needed. Replace it with the value for your application. Learn more in our guide to generator kVA.
The HP conversion uses mechanical horsepower: 1 HP ≈ 0.7457 kW. Divide shaft output by motor efficiency to find electrical input, then use phase, voltage and power factor to calculate running current.
About 7.46 kW at the shaft, 8.29 kW electrical input and 14.95 A on a balanced three-phase supply.
Starting a motor can impose a much larger demand than running it. The starting method matters; see Schneider Electric’s motor guidance. This tool calculates running values.
Explore Blackwell, FW Power’s own generator brand, or discuss new and used diesel generators with our UK team.
Compare new diesel generators and used diesel generators, with brand information for CAT, Cummins, Doosan, Baudouin and Perkins.
Help with generator amps, power factor and the information to gather before choosing your next set.
Ask FW Power a questionAt 400 V with a balanced three-phase load, 100 kVA corresponds to approximately 144.34 A per line. At 415 V it is approximately 139.12 A. Enter the voltage on the generator specification: changing voltage changes the current for the same kVA.
Divide real power in kW by power factor. For example, 60 kW at 0.8 PF is 75 kVA. Check both the kW and kVA ratings of a proposed generator against the application; the converted figure alone is not a model recommendation.
Enter the line-to-line voltage, such as 400 V, rather than the voltage from a line to neutral. The calculator assumes the load is balanced across all three phases. Single-phase loads on a three-phase generator also require a phase-balance check.
Horsepower on a motor describes mechanical output at the shaft. A 10 HP motor delivers about 7.46 kW mechanically; at 90% efficiency it needs about 8.29 kW of electrical input. Its running current also depends on voltage, phase and AC power factor. Starting current is separate.
Yes. Electrical unit conversions apply to both new and used generator sets. For a used set, also check its rated voltage, phase, duty, condition and documented load-test performance. FW Power can help assess available stock against your requirements.
It provides a starting point for your specification. Final selection needs the complete load schedule, starting sequence, permitted voltage and frequency changes, site conditions and operating duty. Send the calculation to FW Power with details of your equipment for a project-specific review.
Use Print result to save a paper copy or choose Save as PDF in your print dialog. Email this calculation opens your email application with the inputs and result included. Add your project details and send the message to FW Power when ready.
Tell us what you need to power. We’ll help you find the right solution.