Single gang plastic nail-on box

[Jimmy7]

Is it permissible to install two 14-2 romex through one slot/ knockout of a Carlon single gang box? I see this a lot, three cable entering the top of a single gang box. Two in one slot, and one in the other.

 

[Joe Villani]

Yes
See 314.17(B)(2) Exception

A Carlon single gang plastic box doesn't have a clamp.

The code uses the phrase multiple cable entries and doesn't specific an amount.

 

[Joe Villani]

Even the P&S or slater boxes with clamps permit multiple cable entries through the same clamp as per the instructions

 

[augie47]

Whenever I'm asked about that I can't help but think how ludicrous it is to call those "tabs" as clamps in Carlon multigang boxes

 

[curt swartz]

Even the P&S or slater boxes with clamps permit multiple cable entries through the same clamp as per the instructions

I have never seen any NM box manufacture show more than 1 cable per clamp. I just looked up the instructions for P&S multi gang boxes and it states 1 cable per clamp. Single gang boxes which don't have clamps allow multiple cables per K.O.