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#129516 04/05/05 07:28 PM
Joined: Jun 2004
Posts: 2
K
knopp Offline OP
Junior Member
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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Joined: Mar 2001
Posts: 2,056
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Member
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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