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NEC Motor Flying Lead Requirements

NEC Motor Flying Lead Requirements

NEC Motor Flying Lead Requirements

We have a single phase, 1/2a, 120v motor which came without a terminal box (flying leads only).

The question is, can we protect the conductors in the following manner?

 1) Mount a box within 6" of the motor.
 2) Heat shrink or spiral wrap the leads.
 3) Run the leads into the box with a bushing / CG fitting.

Thanks in advance.

RE: NEC Motor Flying Lead Requirements

Hi crheater,

Your problem is hard to visualize. Will the leads be enclosed by nothing?

This forum doesn't get much action -- you might get better results by red-flagging this post and re-posting in the electric motors, generators, and controls engineering forum.

Good on ya,

Goober Dave

RE: NEC Motor Flying Lead Requirements

Thanks for the reply DRWeig.  

The wires (THHN) will be covered with spiral wrap and heatshrink.  They will be affixed to the frame using mechanically attached tie wrap pads.  They will enter the J-Box through a CG fitting.

The question is, will spiral wrap and heatshrink be ok for that 6" run between the J-Box and the motor?  Is it "NEC Safe"?


RE: NEC Motor Flying Lead Requirements

It is my opinion, but I can't put a code section to it, that the motor conductors must be protected with a type of raceway that is found in Chapter 3 of the NEC.  I thought that there was a specific section of Article 430 that addressed this issue, but I can't find it.

RE: NEC Motor Flying Lead Requirements

Yah, I agree with resqcapt19.  

It's unusual.  If it were me, I'd either:

Never seen anything other than listed raceway approved for thhn wire.  Normally a motor that small will have SJ rubber cord attached with strain relief.

1) Call up the electrical inspector who's going to rule on it and ask about your proposed heat-shrink / spiral wrap method, or,

2) Stick it in a short section of 3/8" flexible metal conduit and be done with it (provided there's a way to attach a fitting to the motor), or,

3) Exchange the motor for one with a terminal box or something.

Good on ya,

Goober Dave

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