running contorl wire in same conduit. NEC

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redbandit98

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hello guys, this is my first post. I am sorry to even bother you guys but I am having problems with a certain question. First off, I am taking a "test" here at work. Dont worry, I can ask for help. I have spent quite a bit of time trying to find the answer myself. It may be I am looking in the wrong section. I have read over several sections of the NEC and have not found anywhere that prohibits you from running the control wires of a motor with the feeder wires. Now, with that being said I would never do this personally. I dont think its good practice, especially with bigger motors. Pulling a 1/0 wire in with a #14 could definately cause damage to the smaller wire. I have been told the answer they want is there is a HP limit on this, and I can not find the ref to it in the book. I have found that all wires of different voltages must have the same class of insulation but thats it. Anyone have a specific answer? I thank you very much.
 
As long as the control circuit is not a class 2 or 3 control circuit you can run with the power conductors.

If it is just the motor and control in the raceway why run two raceways?

Multiple motors and controls you have to think about it more.
 
Thanks for your response. I also found that reference when I was doing my research. I could not see where it had a specific power rating for running a 120v/480 circuit together in the same raceway. As for your question on why run two raceways its a matter of damaging the wire IMO. Pulling some 2/0 coppper in the same pipe with a couple #14 poses a risk of damaging the smaller wires. I would not see a problem doing it on small motors say under 20 horse or so.
 
Why would pulling 14's with 2/0's be damaging to the 14's? They should all be pulled at same time making any risk of damage pretty minimal.

I've run into this when making a long run to a motor where the motor is kind of out there all by itself, but then there is a limit switch or some other device near the motor, or even internal thermostat inside the motor.
 
kwired said:
Why would pulling 14's with 2/0's be damaging to the 14's? They should all be pulled at same time making any risk of damage pretty minimal.

I've run into this when making a long run to a motor where the motor is kind of out there all by itself, but then there is a limit switch or some other device near the motor, or even internal thermostat inside the motor.
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The problem occurs when the small conductors run on the outside of the larger ones when pulling around bends. This path is longer and if the small conductors cannot slide by the other conductors to make up the length, they break. It would normally only happen on longer runs with multiple bends.
 
don_resqcapt19 said:
The problem occurs when the small conductors run on the outside of the larger ones when pulling around bends. This path is longer and if the small conductors cannot slide by the other conductors to make up the length, they break. It would normally only happen on longer runs with multiple bends.
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I can understand that. Have never had a problem with it, but can't recall an installation that was excessively long. I don't really run into situations where doing such an install with raceways larger than 2 inch either so that would also reduce how much shorter the smaller conductor path may be.
 
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