Motor disconnect switch NEC 430.109

[a10jp]

Hi, as I reading NEC Sec 430.103, regarding operation of the disconnect means for motor, I was puzzled why it stated disconnect mean must be rated for the locked rotor current, in case when the motor controller fails, which has its own overcurrent protection elements. If I only have a small motor unit (like a fraction HP fan coil unit), will using a simple single pole switch (within sight of the equipment)comply with the intent of the code, as the intent of the within-sight disconnect mean is only to disconnect the ungrounded phases of the equipment. However, in 430.109, it listed only 7 types of switch that is considered acceptable, a simple switch is not listed as one of those. I would think a simple switch would not be acceptable for motor disconnect.

 

[jraef]

Only if it says "rated for xxxHP" which, by implication, means it has been tested at the requisite Locked Rotor Current for that rating. You can buy cheap junk toggle switches that have little or no HP rating, and you can buy better one's that do have it.

You get what you pay for.


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[a10jp]

Hi thanks for the input. Obviously you get what you pay for. But from the compliance standpoint, apparently NEC art. 430.109(B) allows the circuit breakers to be served as the disconnect for motors size 1/8hp or less, and therefore the simple switches are just for turning on/off the fan coil units, which is the designer intended. Thanks.