Hello all. First, I hope everyone here had a nice and relaxing labor day weekend! My wife and I went to visit her parents for the day and, of course, overeat.
While we were there, I took a look at some wiring for an addition that was being built onto their house. The licensed electrician doing the job used a strange combination of single, two and three gang romex boxes (with the integral clamps in the back) and boxes with only 1/2" KO's. What immediately caught my eye about the KO boxes was that the romex clamps used to secure the wires were installed WITH THE CLAMP INSIDE THE BOX, not on the outside, the way I always thought it was supposed to be done. Besides taking up a lot of room inside the box that could better be used by wires and switch/receptacle bodies, is there any sort of code reference which does not allow this sort of thing?
I would think that, besides just looking really weird, there might be an issue of the sharp edges of the clamp damaging the wire insulation.
Have any of y'all ever run into this kind of thing before? I can't think of any logical reason for anyone (especially a licensed sparky) to do this.
I have seen this in retro work where an enterprising guy actually fished into/out of a hole and managed to catch a locknut along the way. It just added a wire "tick" on the box fill for me. I don't see a problem as long as they don't run out of inches in the box.
Not sure if it's against code, but definitely something out of the usual. After all, I dont think anyone would install an EMT connector backwards (Except for one thread from a while back about a temp guy doing that, did a search but couldn't find it.)
But then again, if it was the only option (such as the clamp goes in the back and the wall is too thin), it's better than no clamp.
The times I have seen it they actually fished out the hole and into another hole. Like I said, an enterprising guy. There was never access to the cable on the other side of the boxes. More recently I have seen them use the plastic clamp, still installed inside to out.
PE: In this case, the boxes were installed in ordinary 2x4 stud walls. Romex entered the top and bottom of various boxes, and in a couple of instances, the guy crammed two or three romexes through one clamp into a single gang box containing a receptacle, so I am sure there are some box fill issues that need dealing with. I mentioned these problems, and several others which I observed, to my father-in-law. His response: "Oh well, it's done, and it must be all right since he is licensed."