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motor disconnect question #129516
04/05/05 06:28 PM
04/05/05 06:28 PM
K
knopp  Offline OP
Junior Member
Joined: Jun 2004
Posts: 2
richmond, va
i have two 480 3 phase motors, the first is a 10HP (14FLA)and the second is a 30HP (40FLA) these two are to be fed from individual circuit breakers at a main lug panel and a fusible disconnect supplies the incoming power. how do you properly calculate for the correct size time delay fuses at the disconnect.

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Re: motor disconnect question #129517
04/05/05 08:29 PM
04/05/05 08:29 PM
R
Redsy  Offline
Member
Joined: Mar 2001
Posts: 2,056
Bucks County PA
How about 430.63, which would, in your case put you at 430.62?
40A x 175% = 70A
70A + 14A = 84A
84A + the lighting and appliance load on the panel = Time Delay Fuse size?

[This message has been edited by Redsy (edited 04-05-2005).]


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