How do you make a watertight connection between PVC conduit and a metal enclosure?

[Installer]

How do you make a watertight connection between PVC conduit and a NEMA 3R metal enclosure?
In this case, the metal enclosure sits under an overhanging eave and is directly out of rain so we feel
safe entering on the side and not bottom. (Is this okay?)
How do we run a 2 inch PVC conduit into the enclosure ?
If it were aluminum or metal conduit, we would use a conduit hub..
PVC coated conduit hubs are like $250. Could we just use a meter base?
We're trying to keep costs down.

 

[infinity]

I think that the only code recognized way would be a sealing locknut.

 

[LarryFine]

An O-ring, or enter lower than energized parts inside.

 

[marmathsen]

Funny. I just asked this question a few weeks ago.

How do you seal PVC entering an enclosure in a wet environment

When you have PVC entering some sort of box or other enclosure outside (top or side entry), do you seal the the TA to prevent water intrusion? LFMC and LFNMC connectors both come with sealing O-rings, but PVC TAs don't. Do you buy them separate and install them? My supplier seemed totally...

forums.mikeholt.com

Rob G - Seattle

 

[Eddie702]

Why risk a problem if you can go in the bottom or the lower side below any energized equipment?

 

[Installer]

Why risk a problem if you can go in the bottom or the lower side below any energized equipment?

Oops this is antenna cable, not electrical wiring. The enclosure is a polyphaser box.

 

[infinity]

A junction box in a wet location (even with power condcutors) has no below the live parts exception for conduit entries.

 

[ptonsparky]

Arrange to drain. Weep holes.. RV silicone. Expanding foam. Duct seal.

 

[electrofelon]

I think that the only code recognized way would be a sealing locknut.

Rob I'm pretty sure sealing locknuts are for RMC and IMC only. Unless you mean to transition to a RGS nipple using a FA then the sealing lock nut on the nipple. I believe that method or get one of those o-rings would be the only compliant method. Oh, or the RGS transition method then into a Meyers hub.

 

[infinity]

Rob I'm pretty sure sealing locknuts are for RMC and IMC only. Unless you mean to transition to a RGS nipple using a FA then the sealing lock nut on the nipple. I believe that method or get one of those o-rings would be the only compliant method. Oh, or the RGS transition method then into a Meyers hub.

Do they make O-rings for PVC terminal adapters? Maybe they do make them but I've never seen a TA that came with an O- ring.

 

[ptonsparky]

Do they make O-rings for PVC terminal adapters? Maybe they do make them but I've never seen a TA that came with an O- ring.

I think they are available at TSC.

 

[TwistLock]

Couldn't you just glue a male fitting on and adapt to a Myers Hub ?

 

[electrofelon]

Do they make O-rings for PVC terminal adapters? Maybe they do make them but I've never seen a TA that came with an O- ring.

Yes the PVC conduit manufacturers make them specifically for this purpose, but if I remember correctly they are only available up to 2 in. I have actually never seen or used one however.

 

[electrofelon]

Couldn't you just glue a male fitting on and adapt to a Myers Hub ?

Technically Meyers hubs are also only for IMC and rigid. I mean it's done all the time and I've never heard of anybody getting called on it but technically that's the way it is.

 

[Geber]

Oops this is antenna cable, not electrical wiring. The enclosure is a polyphaser box.

Do you mean PolyPhaser made the box, or it is a box made by somebody else that contains PolyPhaser surge protectors? I've used the surge protectors but never noticed any boxes being available from PolyPhaser.

 

[don_resqcapt19]

Do they make O-rings for PVC terminal adapters? Maybe they do make them but I've never seen a TA that came with an O- ring.

I know Carlon has one, but even though it looks like an O-ring, they call it a flat sealing washer. It is my opinion that it would work better it it actually was a flat sealing washer.

 

[TwistLock]

Technically Meyers hubs are also only for IMC and rigid. I mean it's done all the time and I've never heard of anybody getting called on it but technically that's the way it is.

Are you using Sch 80 ?

 

[ptonsparky]

Are you using Sch 80 ?

Hmmm, threads?

 

[infinity]

Rob I'm pretty sure sealing locknuts are for RMC and IMC only.

I'm not sure why. A terminal adapter uses a standard locknut so why should a sealing locknut be any different?

 

[don_resqcapt19]

I'm not sure why. A terminal adapter uses a standard locknut so why should a sealing locknut be any different?

Just like a lot of things, ...they have only been evaluated for use with rigid or IMC.
From the UL Guide Information for "conduit fittings (DWTT)"

Sealing (Liquid-tight) Locknuts — Sealing locknuts are intended for use with threaded rigid metal conduit and intermediate metal conduit with one sealing locknut on the outside or the inside and either an ordinary locknut or sealing locknut on the inside of the enclosure for wet locations or liquid-tight applications. Sealing locknuts may also be used with certified wet location or liquid-tight fittings where so marked on the fitting carton and used on the inside of the enclosure.