I was wondering the other day about this… the Romex cable clamps shown in the attachment… does it matter which side the clamp portion goes on?
I’ve always used these for JBs with the clamp on the outside of the box, locknut on the inside. However, the other day I came across where someone had used them on handy boxes with the clamp on the inside, locknut on the outside.
So… does the orientation matter? Thanks!
Replies
I am not sure about code issues, but in a jam I have done the same. Especially when the box is in place. I would think that it would diminish the physical area to fold wires into.
Just be careful not to nick the wires on an edge.
Webby
Yup... similar thoughts. It looks weird to me but I started thinking that, neglecting the fact that you are cutting down on your box capacity (i.e. box fill calcs need to take into account the clamps now)... it can be useful to have the clamp side inside the box so as to allow you to perhaps fish a second wire in later. That's assuming 1. only one (or no) cables are in the clamp, and the clamp is rated for 2 cables of the size that you want to put in.
Like I said, looks weird to me, but I don't know of any NEC rule that would be broken using this approach.
The rule, if any, would not be in the NEC other than indirectly.What would control this is the UL or similar approval.You can only use materials in the mannor inwhich they wheere approved..
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A-holes. Hey every group has to have one. And I have been elected to be the one. I should make that my tagline.
I was thinking the same thing, that when in doubt, look at how the part is rated/directed to be used. I went and quickly looked at cable clamps from two different manufacturers and found nothing.
I agree with the other comments about the clamp and the potential to cut into the wire...
I do it that way sometimes when hanging a fluorescent fixture and there is plenty of room inside of the fixture (not the type with the removeable cover with the knockout) and little outside and not a lot of wire available to work with. Would be real careful in a box. If things are too tight use one of the plastic push-in types (I hate them though).
The inside of the threaded end of the clamp is rounded, to allow the wires to be bent at tight angles without damage to the insulation. This is more a theoretical than a practical issue, though.
Biggest problem would be the clamp getting into the way, or possibly shorting out a terminal on a receptacle installed in the box.
I always put the nut on the inside of the box unless the outside of thed box will be inaccessible. In that case the nut goes on the outside.
I have always found that I can't run the screws in far enough to clamp a single cable when I put the clamp part on the inside of the box. If you're running two cables through the same clamp, I can see how that would work out.
George Patterson