Power factor is the percentage of apparent power that becomes real, working power. A diesel generator rated at 0.8 power factor converts 80% of its kVA output into kW. The remaining 20% is reactive power, which magnetic loads such as motors and transformers require but do not convert into mechanical work.
The useful power that actually does work — turning motors, heating elements, and lighting lamps. It is what your appliances consume and what you pay for.
The total power a generator must supply. It is the vector sum of real power (kW) and reactive power (kVAR). Generators are rated in kVA because their alternators are sized by current.
A generator rated at 0.8 PF delivers 80 kW for every 100 kVA. The remaining 20% is reactive power — required by motors but not converted into useful work.
You size in kW (your real load), but you buy in kVA (the generator's nameplate rating). Miss the conversion and you either pay for capacity you cannot use or, worse, overload a unit that cannot start your largest motor. Always convert your load to kVA before specifying a generator.
The ratio of real power to apparent power. A PF of 0.8 means 80% of the current does useful work — 20% is reactive.
Magnetic loads like motors and transformers require reactive power to create magnetic fields. It does no useful work but must still be supplied by the generator.
A 100 kW load at 0.8 PF requires 125 kVA. At 0.7 PF, the same load requires 143 kVA — always convert before specifying.
Miss the conversion and you either pay for capacity you cannot use or overload a unit that cannot start your largest motor. The calculator handles this so you do not.
The relationship between kilovolt-amperes (kVA) and kilowatts (kW) is a single formula. Understanding it is the fastest way to stop overbuying or undersizing your generator. Most diesel generator sets are rated at a power factor of 0.8.
Enter the generator's kVA rating and power factor. The calculator returns the real power (kW) available at full load. Default power factor is 0.8 — the industry standard for diesel generators.
Enter your load in kW and power factor. The calculator returns the required generator kVA rating. Use this when you know your real load and need to specify a generator.
Typical kVA ranges by application give you a fast starting point. These are planning estimates, not engineering values — always confirm with the kVA calculator and a full load list. Every row maps to a product range Shandong Huali manufactures in‑house.
| Application | Typical Load | Recommended kVA Range |
|---|---|---|
| Data center (critical IT) | 200–2,000 kW | 250–2,500 kVA |
| Hospital (emergency standby) | 100–1,000 kW | 125–1,250 kVA |
| Construction site | 20–200 kW | 25–250 kVA |
| Mining operation | 200–1,500 kW | 250–2,000 kVA |
| Factory / manufacturing | 50–500 kW | 60–625 kVA |
| Agriculture / irrigation | 10–100 kW | 15–125 kVA |
For three-phase systems, current is calculated as: Amps = (kVA × 1,000) ÷ (√3 × Volts). A 100 kVA generator feeding a 415 V three-phase supply draws approximately 139 amps.
For balanced three-phase systems, divide the product of kVA and 1,000 by 1.732 × line‑to‑line voltage. This formula accounts for the phase relationship between the three legs of a three-phase circuit.
For single-phase systems, the √3 term is dropped. Current is simply the apparent power divided by the voltage. This applies to residential and small commercial generator feeders.
100,000 ÷ (1.732 × 415) = 139 A
This is the full‑load current the generator must supply. Use this value
for sizing cables, circuit breakers, and transfer switches.
A generator sized correctly in kVA but wired for the wrong current will still fail at the panel. Use the kVA calculator to keep all three figures — kVA, kW, and amps — consistent.
50 kVA ≈ 70 A | 100 kVA ≈ 139 A | 200 kVA ≈ 278 A | 500 kVA ≈ 696 A | 1000 kVA ≈ 1,392 A
Three-phase: Amps = (kVA × 1,000) ÷ (√3 × Volts)
Single-phase: Amps = (kVA × 1,000) ÷ Volts
Use the kVA calculator to convert your load and get all three values
— kVA, kW, and amps — in one view.
A sizing tool is only as good as the manufacturer behind it. When the kVA calculator recommends a 250 kVA unit, we can build that exact generator — not the nearest model in a fixed catalog. Here is how we deliver that promise.
We produce diesel generator sets from 8 kVA to 4,000 kVA across silent, open, trailer, container, and high‑voltage configurations. Buying factory‑direct removes intermediaries and their markup.
Standard generators do not fit every project. Our engineering team of 80+ specialists designs to your specification — voltage, frequency, enclosure, control system, and engine choice.
We integrate Cummins, Perkins, Weichai, and Yuchai engines with Stamford alternators, matched to your duty cycle and budget. Every combination is load‑tested before delivery.
Every unit is 100% load‑tested in our national‑standard testing center before delivery. Our processes carry ISO9001, CE, CCC, and ISO14001 certification.
With over 25 years of manufacturing experience and exports to 20+ countries, we stand behind every generator we ship — from design to installation to after‑sales service.
From design to installation to after‑sales service, our engineers provide end‑to‑end technical support wherever your project operates. We are with you at every stage of the generator lifecycle.
A generator is an investment in reliability. Our quality systems and support infrastructure ensure that your generator performs when it matters most — and stays performing for years.
Our manufacturing processes are certified to ISO9001, CE, CCC, and ISO14001. Every generator is built in a quality‑controlled environment with documented traceability.
Our engineering team customizes every aspect of your generator — from engine and alternator selection to control system programming and enclosure design. Standard models are only the starting point.
We export to over 20 countries across Asia, Africa, the Middle East, and the Americas. Every shipment is packaged for international transit and supported by remote technical assistance.
From design and manufacturing to installation, commissioning, and after‑sales service, our engineers provide end‑to‑end technical support wherever your project operates.
Standby, prime, or continuous — we match the generator to your actual operating profile, not a catalog default. Every unit is 100% load‑tested at our national‑standard testing center before delivery.
Final generator selection should be made against the complete load schedule, motor‑starting sequence, power factor, site conditions, and duty rating. Use the kVA calculator to convert your load from kW to kVA, get the amps and horsepower, then match the result to a Shandong Huali generator built for your application.
Tell us your computed kVA, application, and location, and a sizing engineer will review your load and respond with a tailored specification — no pressure, no hard sell.
A: kW is real power — the energy that actually performs work. kVA is apparent power — the total the generator must supply, including reactive power. Power factor links them: kW = kVA × power factor. For a diesel generator at 0.8 PF, a 100 kVA unit delivers 80 kW.
A: Multiply kVA by the power factor. For a diesel generator rated at 0.8 power factor, kW = kVA × 0.8. A 125 kVA generator therefore produces 100 kW.
A: At a 0.8 power factor, 100 kVA equals 80 kW. At unity (1.0) power factor, 100 kVA equals 100 kW. Always confirm the generator’s rated power factor before converting.
A: Add the running power of all connected loads, then add the single largest starting surge, apply a 20–30% margin, and convert kW to kVA by dividing by 0.8. Use the sizing mode of this kVA calculator to automate the process.
A: On a 415 V three-phase supply, a 100 kVA generator produces approximately 139 amps. The formula is Amps = (kVA × 1,000) ÷ (√3 × Volts).
A: Power factor is the ratio of real power (kW) to apparent power (kVA), expressed as a number between 0 and 1. Diesel generators are commonly rated at 0.8, meaning 80% of apparent power becomes usable real power.
