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Fire Pump with Arc Reduction Breaker

Question asked by j_w_hines on May 7, 2019
Latest reply on May 10, 2019 by j_w_hines

The pump is 150HP and the circuit breaker disconnect is sized to exceed locked rotor at1200A.  Based on NEC 240.87, the disconnect has a maintenance mode switch, which reduces the instantaneous setting for live work. If accidently left in the 'ON' position it would most likely cause the breaker to trip and the fire pump not run. Does anyone have experience with this or is there a way to get a code committee to investigate this?  For critical systems, possibly the fire alarm supervisory mode should monitor the switch position. 

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