Fuse size for motor starters

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Flex

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poestenkill ny
I have a combination motor starter for an AC with 60 amp fuses on the disconnect. The FLA on the motor is 8.7 amps with a service factor of 1.15. Its feed with #12 solid and on a 3 pole 20amp breaker. Why the 60 amp fuses?
 
From a NEC standpoint, as Nakulak states, as long as the motor is properly protected your are fine. You might want to check data for your starter. Some starter manufacturers recommend a max fuse sixe to better protect the starter in case of a short.
 
I've never seen a MCC that was protected by a fuse AND breaker,,,,it's usually one or the other,,,,,change,,,,remove ,,,,or leave them,,,it's still fine because of the breaker
 
Its most likely as the max fuse size for the combo starter is 60 amps.
Fuse reducers are available but you would want to go to about a 15 amp fuse. You don't state the motor hp or voltage so I am guessing.

Dual element time delay fuses will protect the motor far better than a CB, but some don't like fuses as if one blows the motor can single phase. I use IEC overloads and don't have that problem, plus if you size the fuses at 125% of FLA, then the fuse backs up the OL. Single phasing can happen on lightly loaded motors.
You motor is protected by the 20 amp OCPD, a 15 may be a bit better, but it depends on the cost of the motor.
 
Yes sorry for the lack of info. They are 3phase 208v motors. There are overloads on the contactor so it cant single phase. The motor starter is rated for 60A thats why I think they sent those fuses. Now I need to get fuse reducers, its just a pain.
 
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