Running cables through boxes

Well, if you are wiring DSO etc, via singles in conduit, then you will be running wires through that / all boxes.

I admit I did this once in a domestic situation. In a kitchen for a row of 13 A sockets I ran the "other side of the ring" through some boxes. The job looked neat when I finished but I had afterthoughts about whether I was leaving a difficult situation for anyone subsequently wishing to remove the box for any reason.


Several years later I did a similar job in another kitchen. This time, with a little extra chipping and chasing, I ran the non-terminated cable behind the boxes. This also looked neat when I finished.


I can think of some rare occasions when I have needed to remove a box. In one case involving a very old box, a screw had rusted in and sheared when I tried to remove it, leaving a stub on the screw hole. Other cases have been upgrading from a single to a twin. Modern galvanised boxes should not have rust problems and it is usual to instal twin accessories from the outset for multiple 13 A sockets. For large adaptable boxes it is extremely unlikely that these would be removed and with conduit installations it is not difficult to add new jointing terminals anyway. I would not like to try to rejoin a flat-twin-and-earth cable with no spare length.


The reason why luminaires have cable entry at each end is surely to facilitate parallel wiring where these are installed in rows, e.g. along a corridor? 


On balance, I would not run non-connected cable through a box or fitting nowadays. However we are considering a rare scenario. It is not worth a heated argument with rude words.

A long no.6 wood screw is very useful if the threaded lug in a metal back box has stripped. Also a very long no.6 wood screw can be used to hold one side of an accessory if a threaded lug has been lost or badly damaged. Just drill through the metal back box in line with the accessory fixing screw hole, and plug the hole with a plastic wall plug. The long no.6 screw can then fit through the accessory hole and be secured into the wall plug. An earth linking wire may be needed from the metal box earth terminal to the accessory earth terminal.


Z.

I agree with the pragmatic approach on this forum ... if the boxes are in line and on the same circuit, no issues running through. To be fair to my colleague, I DO have a habit of pointing out the regs to him and it was the end of a long day <grin>


With regard to the snapped lugs, I have my own homebrew solution.


M8 studding with an m3.5 hole tapped in the end, cut to 25mm lengths. drill and tap an M8 hole in the backbox behind the missing/damaged lug, and locktite one of these doofers in.


Not something you'd make up on the spot, but in finished walls (think tiled kitchen) it can be a lifesaver. I sat and made 10 of them in front of youtube one night, got 7 left, but the 3 that are missing impressed the customers no end :)

A couple of good ideas in the previous two posts, if it is not practicable to remove the box, though they do sound as though there is a fair bit of work involved. If there is the stub of a screw stuck in the lug, then the lug could be sawn or snipped off (more easily said than done I think but possible).


If it is not too difficult to remove the box I would prefer to just replace it - less hassle overall.