Junction Box Extensions

[jim1]

I have a junction box 8x8x8 in concrete - is it a code violation to use self tapping screws to hold the extension box to the one in concrete ??

 

[mdshunk]

I sorta doubt it, but I'm not sure how the UL investigates the bonding continuity of extension boxes. If I did connect the extension box on with tappers, I'd probably try to drill and tap the side of the extension box for a bonding pigtail if I could.

 

[infinity]

Why not use the original box cover screws? Or were you planning on using the self tapping screws in the existing holes?

 

[chris kennedy]

Where did you get an 8 by 8 extension box? Is it metal?

 

[cadpoint]

I have a junction box 8x8x8 in concrete - is it a code violation to use self tapping screws to hold the extension box to the one in concrete ??

A box, connected to another Box, Bolt it. The old application of making it mechanically fasten, 1/4 twenty bolt , lock washer and nut ... (or fender washer)

 

[mdshunk]

Where did you get an 8 by 8 extension box? Is it metal?

I was kinda wondering the same thing. I just assumed it existed, since he's talking about using one.

 

[jim1]

the boxes were made for this application-- the self tap screws are not used for grounding , they have a jumper-- no they are not using the originial cover screw hole--

i can't find anything in the nec -just wondering about the sharp ends if the self tap - i had suggested nut bolt

 

[Jim W in Tampa]

This might go to the listing book

 

[chris kennedy]

This might go to the listing book

I've read enough crap today.

 

[RUWired]

I have a junction box 8x8x8 in concrete - is it a code violation to use self tapping screws to hold the extension box to the one in concrete ??

Unless you drill and tap a bonding jumper like md said, i think it would violate 250.8

Grounding conductors and bonding jumpers shall be connected by exothermic welding, listed pressure connectors, listed clamps, or other listed means. Connection devices or fittings that depend solely on solder shall not be used. Sheet metal screws shall not be used to connect grounding conductors or connection devices to enclosures.

 

[Jim W in Tampa]

I've read enough crap today.

Sounds like bad day.Had one of them myself.It can get worse with red tag