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Generator sizing
Generator kW + kVA for a connected load. Accounts for the motor-starting surge (typical 3-6x running current) by letting you input both running and surge kW separately.
Recommended generator
150 kW(≈ 188 kVA)
Running case: 150.0 kW (with 1.25× load factor)
Surge case: 117.0 kW (≈ 65% of nameplate handling)
Governing: 150.0 kW
Surge case: 117.0 kW (≈ 65% of nameplate handling)
Governing: 150.0 kW
Standard generator sizes: 20, 30, 45, 60, 80, 100, 125, 150, 200, 250, 300, 400, 500, 600, 750, 1000, 1250, 1500, 2000 kW. For motor-heavy loads, the surge case usually governs; confirm with the manufacturer's voltage-dip curve.
How it works
We size on whichever is larger: (running kW × load factor) or (surge kW × duty factor). The generator must handle the inrush without dropping the bus voltage below the sensitive-load tolerance. For motor-heavy loads (pumps, elevators), the surge case usually governs.
Built by Forward
Forward runs generator sizing, transformer kVA, wire- size, panel demand load, NEC calcs, plus project lookups over text.