Bell box in concrete.

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chris kennedy

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Location
Miami Fla.
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60 yr old tool twisting electrician
I got a bunch of back boxes today for LED step lights to be set in masonry. They are nothing but a round bell box with round bell X-ring. Instructions state install flush with finished wall or ceiling.

The is no make or model number, but it does have the UL, box fill cast markings. Question is, can a bell box be poured in concrete or installed in a masonry unit?

Thanks.
 
My experience with aluminum and concrete has not been good. I once had aluminum RMC turn to paste where it passed under an outdoor concrete slab because of the constant moisture leaching alkali from the slab. As for Bell boxes I see no prohibition like there is for RMC, but that doesn't mean that it's suitable. You don't say whether this is indoor or outdoor but PVC would be the proper solution outdoors.

-Hal
 
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My experience with aluminum and concrete has not been good. I once had aluminum RMC turn to paste where it passed under an outdoor concrete slab because of the constant moisture leaching alkali from the slab. As for Bell boxes I see no prohibition like there is for RMC, but that doesn't mean that it's suitable. You don't say whether this is indoor or outdoor but PVC would be the proper solution outdoors.

-Hal

Sorry Hal, outdoors next to the Intracoastal waterway.
 
I'm looking at the installation instructions for a Bell 5322-0. Number two states "Mount box to surface".
 
Chris. Installed in cement it will turn to dust
We see a lot of jobs where they were installed and It gives us plenty of replacement work
 
Pouring concrete all around it will "mount it". Of course that not on the surface, but its splitting hairs.

if you can tape a standard EMT coupling and its "concrete tight" why not a bell box with siliconed KO's?

Now whether or not it will rot, is another thing.
 
My experience with aluminum and concrete has not been good. I once had aluminum RMC turn to paste where it passed under an outdoor concrete slab because of the constant moisture leaching alkali from the slab. As for Bell boxes I see no prohibition like there is for RMC, but that doesn't mean that it's suitable. You don't say whether this is indoor or outdoor but PVC would be the proper solution outdoors.

-Hal


What about aluminum strut mounted to a block wall with constant moisture. Haven't ran a lot of aluminum, but running it a lot more these days. One more off topic question. Would aluminum conduit be considered rmc as far as the code is concerned?
 
What about aluminum strut mounted to a block wall with constant moisture. Haven't ran a lot of aluminum, but running it a lot more these days. One more off topic question. Would aluminum conduit be considered rmc as far as the code is concerned?
344.2 Definition of RMC: RMC is generally made of steel (ferrous) with protective coatings or aluminum (nonferrous).
 
I got a bunch of back boxes today for LED step lights to be set in masonry. They are nothing but a round bell box with round bell X-ring. Instructions state install flush with finished wall or ceiling.

The is no make or model number, but it does have the UL, box fill cast markings. Question is, can a bell box be poured in concrete or installed in a masonry unit?

Thanks.


110.3(B)

The listing for installing the box flush may not be just for the box itself. LED lighting systems sometimes need to be able to disperse the heat generated. It is possible this may be the reason for the listing. I would definitely contact the manufacturer first.


Here, let me help.........1 ringy dingy, 2 ringy dingy, 3 ringy dingy...........:D
 
I used to see steel octagon boxes embedded in concrete fairly often. Not sure if they were specifically rated for it. Have seen some that have been in concrete a few years. Seem more or less OK, often discolored. Of course, there are single and double gang masonry boxes, labelled for concrete. Would 1 of those fit your application?
 
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