Little help with NEC code on motor overload breaker

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fastline

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Currently looking at a 3 wire, 1P pump start box. There is one overload on the black wire only. This obviously would stop the pump a spinning but it was my understanding that NEC prohibits partial disconnection of a motor like this? Not that I have any concern at all here, I am just curious at the moment. I have seen this many times and I have even done that to protect motors, but obviously there has to be some common sense in place.

Does the enclosure remove the 'all legs disconnected' requirement?
 
fastline said:
Currently looking at a 3 wire, 1P pump start box. There is one overload on the black wire only. This obviously would stop the pump a spinning but it was my understanding that NEC prohibits partial disconnection of a motor like this? Not that I have any concern at all here, I am just curious at the moment. I have seen this many times and I have even done that to protect motors, but obviously there has to be some common sense in place.

Does the enclosure remove the 'all legs disconnected' requirement?
Click to expand...
The code requires that all ungrounded conductors be opened
 
Well that is certainly conflicting guys!!! lol Where is this "controller" deal in the code? I have heard this both ways so curious where the code references are?
 
fastline said:
Well that is certainly conflicting guys!!! lol Where is this "controller" deal in the code? I have heard this both ways so curious where the code references are?
Click to expand...

you can have it both ways...

2017 NEC



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fastline said:
Well that is certainly conflicting guys!!! lol Where is this "controller" deal in the code? I have heard this both ways so curious where the code references are?
Click to expand...
There is not conflict here, just a misunderstanding of the terms as used and defined in the NEC.

A controller is not typically the disconnect, although manual controllers can be both the disconnect and the controller.

430.102(A) requires a disconnect on the line side of the controller, and that the required disconnect be within sight from the controller.
 
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