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Generator Capacity After Manufacturer Derating

Applies a manufacturer-provided usable-capacity factor to a generator nameplate rating. No generic altitude or temperature correction is assumed; obtain the factor for the exact generator model and site conditions.

Inputs

Range: at least 0

Example starting value: 500 in the selected unit. Replace it with the exact generator nameplate rating.

Range: 0–1

Example starting value: 0.90. Replace it with the factor from the exact generator model's manufacturer data for the project altitude and temperature.

Result

Capacity after entered factor (same unit)
450.00
Capacity reduction from entered factor
50.00
Capacity after entered factor (same unit)
\mathrm{Generator\ nameplate\ capacity} \cdot \mathrm{Manufacturer\ usable\-capacity\ factor}
500 \cdot 0.9

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Screening tool. Verify the adopted NFPA 70 edition, AHJ requirements, nameplate data, and project conditions before use.