Threaded RMC into 2 gang w/p box

[infinity]

Just to be clear we put silicone around the outside after the pipe is threaded in.

Bingo, that satisfies the sealing requirement of the box and the NEC.

 

[jap]

Pipe dope, Teflon tape, silicone, Myers hubs in a threaded WP box, etc...

All ridiculous.

You'll do more damage trying to seal it up.

I'll probably be coming along behind you drilling a hole in the bottom of it to let the water out.

JAP>

 

[petersonra]

Citation?

When bonding threaded pressure pipe with joints made with dope, it is assumed that the joint will provide electrical continuity, so there is no need to jumper each fitting. Of course, the standard for bonding conduit may be higher than bonding other systems.

Cheers, Wayne

300.6 Protection Against Corrosion and Deterioration. Raceways,
cable trays, cablebus, auxiliary gutters, cable armor,
boxes, cable sheathing, cabinets, elbows, couplings, fittings,
supports, and support hardware shall be of materials suitable
for the environment in which they are to be installed.
(A) Ferrous Metal Equipment. Ferrous metal raceways, cable
trays, cablebus, auxiliary gutters, cable armor, boxes, cable
sheathing, cabinets, metal elbows, couplings, nipples, fittings,
supports, and support hardware shall be suitably protected
against corrosion inside and outside (except threads at joints)
by a coating of approved corrosion-resistant material. Where
corrosion protection is necessary and the conduit is threaded
in the field, the threads shall be coated with an approved electrically
conductive, corrosion-resistant compound.

My personal opinion is that if one was to use teflon tape or pipe dope on a NPT threaded fitting there would be plenty of metal to metal engagement once it was made tight.

However, the code is pretty clear that if you feel you need to protect a field made thread against corrosion, it has to be electrically conductive.

OTOH, if it is not a field cut thread, I don't see where the code would prevent the use of something non-conductive. Which is just silly, but that appears to be what the code requires.

 

[Strathead]

Are you saying that Bell box instructions require a wire egc bonded to the box?

No I am saying the Bell Box instructions say the box is not considered weathertight unless the threaded entrances are sealed with thread compound or teflon tape.

 

[petersonra]

Does not say you should put silicone sealant on the outside.

 

[Dennis Alwon]

Pipe dope, Teflon tape, silicone, Myers hubs in a threaded WP box, etc...

All ridiculous.

You'll do more damage trying to seal it up.

I'll probably be coming along behind you drilling a hole in the bottom of it to let the water out.

JAP>

The ko is on the side of the box not the top. We would sometimes drill an 1/8" hole in the bottom in case water did build up but is that compliant? IDK but we did it.

 

[infinity]

Does not say you should put silicone sealant on the outside.

Doesn't say to use silicone either. What is "sealing compound" and would it be required to be conductive?

 

[LarryFine]

We would sometimes drill an 1/8" hole in the bottom in case water did build up but is that compliant? IDK but we did it.

I routinely drill two 1/8" holes in the bottom surfaces of boxes, upward-pointing LBs, etc.

 

[jap]

The ko is on the side of the box not the top. We would sometimes drill an 1/8" hole in the bottom in case water did build up but is that compliant? IDK but we did it.

I've never seen a WP box with a KO in it for conduit entry.

JAP>

 

[petersonra]

Doesn't say to use silicone either. What is "sealing compound" and would it be required to be conductive?

The code would only require it if you made a field thread, IMO.

 

[petersonra]

The ko is on the side of the box not the top. We would sometimes drill an 1/8" hole in the bottom in case water did build up but is that compliant? IDK but we did it.

IMO, it is not compliant, although it is OK to drill weep holes in conduit fittings, but a bell box is not a conduit fitting.

 

[jap]

View attachment 2556994

Does not say you should put silicone sealant on the outside.

The box manufacturer is trying to maintain the integrity of their "WP" rating.
The code is trying to maintain the integrity of the conduit and a fault clearing path if used for that.

2 different things.

JAP>

 

[jap]

IMO, it is not compliant, although it is OK to drill weep holes in conduit fittings, but a bell box is not a conduit fitting.

I've never had a need to drill a hole in a condulet fitting.

JAP>

 

[Little Bill]

The ko is on the side of the box not the top. We would sometimes drill an 1/8" hole in the bottom in case water did build up but is that compliant? IDK but we did it.

I've never seen a Bell or other outdoor box with hubs on the sides. For example, a 5-hole would have 1 in the back, 2 on top, and 2 in the bottom. I guess it matters what you are calling "sides". If the box was installed horizontally then what would be top/bottom should it be installed vertical, then you could call it the ends. But I've never seen holes in the long sides of outdoor boxes.

Edit: Just realized the OP was talking about 2-gang! I've been speaking of SG boxes, maybe holes in a 2-gang could be called the side.

 

[petersonra]

here is a five holer that has 1 hole on each side.

1-Gang Weatherproof Box, Five 3/4 in. Threaded Outlets, Gray | 5332-0 | Bell

1-Gang Weatherproof Box, Five 3/4 in. Threaded Outlets, Gray

www.hubbell.com

 

[Little Bill]

here is one that has 1 hole on each side.

1-Gang Weatherproof Box, Five 3/4 in. Threaded Outlets, Gray | 5332-0 | Bell

1-Gang Weatherproof Box, Five 3/4 in. Threaded Outlets, Gray

www.hubbell.com

Now I can say that I have saw one! First one that I ever saw for sure.

 

[Dennis Alwon]

The op turned the box on the side. It was a 5 hole-- 2 on top and 2 on bottom but the box was mounted horizontally

 

[Little Bill]

The op turned the box on the side. It was a 5 hole-- 2 on top and 2 on bottom but the box was mounted horizontally

I realized that after I posted and went back and edited the post to say that. I didn't even read the thread title to say 2-G, I should read slower!

 

[jap]

I'd have to say I think a Meyers hub is primarily designed to be used in a KO and secondly in a threaded opening where a water tight connection cannot be made by either the raceway,or fitting being used.

Jap>

 

[tortuga]

With RMC we dont use anything either.

Doesn't say to use silicone either. What is "sealing compound" and would it be required to be conductive?

Perhaps this:

DOWSIL™ 738 Electrical Sealant

1-part, white, non-flowing moisture cure adhesive, Durable general purpose sealant/adhesive for a wide variety of bonding and sealing applications. Mil spec is required.

www.dow.com