what do you do?

[mjf]

Often when replacing a switch or receptacle in a steel box, I find the old NM cable installed with the bare ground wrapped back around the sheathing. The cable/bare ground is clamped down which bonds the steel box.

Just curious as to if this was ever actually code compliant....as I said, I see it often.

I'm also curious as to what do others do in this situation?

Do you just pop the new device in with a green pigtail to the box?

Do you loosen the clamp, unravel the bare grounds, hit the new device, and re-bond the box?


Do you just drop back 15 and punt?

 

[GerryB]

I have an apartment building like that I work in sometimes. If I change the old fuse box I unwrap the grounds and do it properely. If I change a device I usually leave it the way it was. I worry that the ground might break off because it is smaller than the conductors, but that hasn't happened yet. I don't know if that was ever code, I would guess and say "common practice".

 

[PetrosA]

I'm not 100% sure, but I seem to recall that it was the right way to do it before ground screws were common in residential (maybe '87 or '89?). I kind of remember a period when I first started in resi when wallcases didn't all come with ground screw holes, so we had to remove the second clamp, color the screw head green and bond the box that way. I don't think I had any experience with resi stuff before 1988 - it was all BX and conduit, no ground screws at all.

 

[jumper]

I'm not 100% sure, but I seem to recall that it was the right way to do it before ground screws were common in residential (maybe '87 or '89?). I kind of remember a period when I first started in resi when wallcases didn't all come with ground screw holes, so we had to remove the second clamp, color the screw head green and bond the box that way. I don't think I had any experience with resi stuff before 1988 - it was all BX and conduit, no ground screws at all.

Ground screws for boxes do not have to be green.

 

[jumper]

Often when replacing a switch or receptacle in a steel box, I find the old NM cable installed with the bare ground wrapped back around the sheathing. The cable/bare ground is clamped down which bonds the steel box.

Just curious as to if this was ever actually code compliant....as I said, I see it often.

I'm also curious as to what do others do in this situation?

Do you just pop the new device in with a green pigtail to the box?

Do you loosen the clamp, unravel the bare grounds, hit the new device, and re-bond the box?


Do you just drop back 15 and punt?

I do not believe that any romex clamp is listed for bonding.

I add a bond screw and a jumper to the device.

 

[kbsparky]

I'm not 100% sure, but I seem to recall that it was the right way to do it before ground screws were common in residential (maybe '87 or '89?). I kind of remember a period when I first started in resi when wallcases didn't all come with ground screw holes, so we had to remove the second clamp, color the screw head green and bond the box that way. I don't think I had any experience with resi stuff before 1988 - it was all BX and conduit, no ground screws at all.

You're about 20 years off -- that practice was common in the 1960's ...

 

[Dennis Alwon]

It was common practice but not compliant with the cable clamp still installed. I used to take out the clamp and use the screw but I didn't work much with metal boxes once I left NYC and there NM did not exist.

 

[jumper]

I used to take out the clamp and use the screw

I still do that a lot.

 

[Dennis Alwon]

I still do that a lot.

You need to be careful if it is a deep switch box. The screw will go thru the sheetrock on the opposite side.

 

[jumper]

You need to be careful if it is a deep switch box. The screw will go thru the sheetrock on the opposite side.

True. I use the screw cutter holes on my strippers to shorten them.

 

[PetrosA]

Ground screws for boxes do not have to be green.

They did back then The local inspectors would fail a job with silver screws so we all carried green sharpies. Hey, I was 18 and an employee - not exactly the right person to be arguing with the inspector.

You're about 20 years off -- that practice was common in the 1960's ...

I started in resi in 1988 so I can't say what came before. It seemed then that these were new practices at the time. I honestly can't say I've seen many metal wallcases with holes for ground screws older than 25-30 years old. I think clips may be been common in new work at the time, but the company I worked for didn't use them. IIRC Greenie wire nuts were just coming out too.

True. I use the screw cutter holes on my strippers to shorten them.

You must have some ROCKIN' wire strippers If I don't feel like busting my chops with the lineman's I have to break out my mini bolt cutters to cut those bad boys...

 

[mlnk]

For grounding, I think it is OK to use any threaded holes that are in the box that are not being used for some other purpose, but I think the screws either need to be official terminal screws that have large diameter heads or you need to use crimp on terminals, washer or open end type, with standard machine screws. I do not think terminal screws are required to be painted green or be hexagonal to be used for grounding, but many are manufactured that way to label them. Iusually tap and cut threads for the grounding screw.