Bushings

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Little Bill

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I have an inspector insisting that a bushing (plastic) be used on NM connectors. I'm not finding that in the code. Is it in there or is he mistaken?
 
I agree with Texie this guy is nuts. There not even required on SE cable connectors with conductors #4 and larger.
 
Cable clamps secure the cable in place and keep it from moving, so I can't imagine what good adding a bushing would do??
 
You mean a romex clamp (that has two screws and metal plate that tightens on cable), he wants a bushing on that?
This is where a Mike Holt graphic is needed to show inspector.
 
The only thing I found different concerning raceways and bushings was that PVC seems to require a bushing regardless of conductor size.
 
PVC connectors are sharp!
Yes they can be.

ecmweb_4228_300_04f_un300_13_co8.png
 
A 1/4” jacket is required to protrude fitting. This would provide conductors with protection and provide bushed effect.
 
A 1/4” jacket is required to protrude fitting. This would provide conductors with protection and provide bushed effect.
Pretty sure this been discussed here a long time ago and the results were that the 1/4" thing is mostly only for boxes that are permitted to have direct entry with no clamping device - limiting that to mostly just one gang non metallic device boxes pretty much everything else requires a clamping means.
 
Pretty sure this been discussed here a long time ago and the results were that the 1/4" thing is mostly only for boxes that are permitted to have direct entry with no clamping device - limiting that to mostly just one gang non metallic device boxes pretty much everything else requires a clamping means.
I seem to remember someone mentioned that at some point without any substantiation they added the 1/4" thing for all non-metallic cable connectors.
 
If your nm sheath did not enter the minimum perhaps the inspector saying to add the bushing as a result. Option would be add the bushing or pull in a little more sheath. If this is not the scenario, then as others state he's just wrong.
Many times the inspector might have just gone to a code course and something said (but not fully understood) stuck and he's got the wrong impression of the requirement.
 
So, what about inserted throated fittings? It's not required and basically a waste of money , other than piece of mind through 6 AWG
1669923081429.png
1" shown.
& same with
1669923293307.png
1" shown...

I guess I need to review 300.4(F)
 
So, what about inserted throated fittings? It's not required and basically a waste of money , other than piece of mind through 6 AWG
View attachment 2563035
1" shown.
& same with
View attachment 2563036
1" shown...

I guess I need to review 300.4(F)
In 2020 where I copied this from it is 300.4(G). I think insulated throat fittings fit under (1) or even (3).
A chase nipple on the non threaded end should fit under (2). I think I have seen chase nipples with insulated throat before on the threaded end though so no additional bushings needed if you would have that.

1669991258972.png
 
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