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#90710 - 12/08/04 08:17 AM Fire pump feeder & disconnect
Yoopersup Offline

Registered: 03/04/03
Posts: 826
Loc: Michigan
Fire pump 20hp & booster pump 3/4 hp.460volt3phase

20hp=27amps LRC=145 amps
3/4 hp=1.6 amps LRC 12.5 amps
Disconnect Size 145 +12.5=157.5
240.6 next size up 175amps
175amp disconnect switch
The way I read it from the fire pump locked rotor sized disconnect switch to fire pump controller wire sized at 125 %
27plus 1.6=28.6x125%=28.6
according to the code 175 amp disconnect switch with 30 amp wire from switch to fire pump controller then to the mtr. code handbook 2002 pages 975-976.
Please comment . Thank u

2014 / 2011 NEC & Related Books and Study Guides
#90711 - 12/08/04 04:30 PM Re: Fire pump feeder & disconnect
George Little Offline

Registered: 01/18/04
Posts: 1492
Loc: Michigan USA
Yooper- I see you got it right. You must have had a good teacher
George Little


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