Fire Pump Electric Motor Calculator Icon

Fire Pump Electric Motor Calculator App

Summary: Almost all three-phase electric fire pump motors are NEMA B, squirrel-cage type. This calculator uses the associated standard NEMA B NEC tables to look up the anticipated amperage and minimum conductor sizes.

INPUTS
Phases
Volts
Rated Horsepower
Anticipated Motor Currents
Locked-Rotor Current
Full Load Current
*Source:
ATL / Soft-Start (3-wire) Conductor Sizes
125% FLC (NEC 695.6)
Min Conductor Size
Min Conductor Size

* Must also confirm maximum 5 percent voltage drop at 115 percent of FLC.

Wye-Delta (6-wire) Conductor Sizes
58% FLC (NEC 430.122(B))
Min Conductor Size
Min Conductor Size

* Must also confirm maximum 5 percent voltage drop at 115 percent of FLC.

  • Conductor sizes per NEC Table 310.15(B)(16) (formerly Table 310.16), 75°C column. Types: RHW, THHW, THW, THWN, XHHW, USE, ZW.

Disclaimer: This calculator is for informational purposes only. It is not a substitute for the NEC or any other applicable codes, standards, or regulations. Always consult the NEC and local codes for final determinations.