Fire Pump Controller Sizing Calculator

Size fire pump controller components per NFPA 20 including voltage, current, and circuit breaker ratings

Input Parameters

Results

--
Full Load Amps (FLA)
A
--
Locked Rotor Amps (LRA)
A
--
Circuit Breaker Size
A
--
Min Conductor Size
AWG/kcmil
Note: Fire pump controllers must comply with NFPA 20 Chapter 10 and be listed per UL 218 or UL 1004-1. Circuit breakers are sized larger than normal (300% FLA) to prevent nuisance tripping during motor starting. Conductors must be fire-rated per NEC 695.6.

Reference

Fire Pump Controller Sizing (NFPA 20 / NEC 695): FLA = (HP × 746) / (V × 1.732 × PF × eff) LRA ≈ 6-8 × FLA (across-the-line start) CB sizing: 300% FLA per NFPA 20 / NEC 695.4(b)(2) Conductor: 125% FLA per NEC 695.6 Controller must be listed for fire pump service per UL 218.