PVC Box Outdoors...

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1793

1793

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Louisville, Kentucky
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Inspector
I'm doing a job right now where I need to set a PVC junction box under a deck. I need to bring a 2" in the bottom side and 1-1/4" in the top side. Is there anything special I need know about installing an 1-1/4" PVC connector in the top side?
 
1793 said:
I would say yes. The deck will provide some protection but I think rain is possible. I was thinking I might need a sealing locknut.
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I don't think a sealing locknut is required but is not a bad idea.

Drilling a weep hole in the bottom of the enclosure will do more good even if you keep rain out you will still get condensation inside.
 
1793 said:
I would say yes. The deck will provide some protection but I think rain is possible. I was thinking I might need a sealing locknut.
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I would try not to come in on the top. If you must then better seal it some way. Myers hub would be needed on a panel but i don't think that applies on J box
Might be wise to but silicone over the connections. You not only get water but freezing in winter. That could be major problem if water got in wire nuts
 
1793 said:
I'm doing a job right now where I need to set a PVC junction box under a deck. I need to bring a 2" in the bottom side and 1-1/4" in the top side. Is there anything special I need know about installing an 1-1/4" PVC connector in the top side?
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Depends how picky you want to be. What if you knew that a PVC Terminal Adapter was not listed by UL to enter a PVC junction box on any side? :grin:




I would avoid holes in the top if at all possible. Sealing locknut at least, with silicone. Myer's hub, as Jim said, with a bonding bushing, if the threads are long enough.
 
Jim W in Tampa said:
.. That could be major problem if water got in wire nuts
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I always arrange wire nuts in wet locations to drain water out of the connector as well as provide weep holes to drain enclosures (NEMA 3R enclosures already have weep holes). You can seal raceways and enclosures all you want, water will still get inside somehow, condensation is probably the most common, some component may leak at some point also.
 
Arlington sells listed "O"-rings for PVC male adaptors to make them rated for rain proof installations, we use them all the time, some just go to a hardware store and get the correct size "O"-ring, the O ring goes between the box and adaptor on the outside providing for a better seal (to me) than the sealing locknets which has to also seal the threads because its on the inside.
 
1793 said:
I'm doing a job right now where I need to set a PVC junction box under a deck. I need to bring a 2" in the bottom side and 1-1/4" in the top side. Is there anything special I need know about installing an 1-1/4" PVC connector in the top side?
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Judging by the size of the conduits you are running, I think you should keep 314.28(A)(1) & (2) in mind. If you are running larger conductors that is.
 
Use a PVC terminal reducer that has flange on it put it in threw the inside using PVC glue into the coupling works fine.
 
WinZip said:
Use a PVC terminal reducer that has flange on it put it in threw the inside using PVC glue into the coupling works fine.
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I don't care for those box adapters, you can't take your conduit back out of the box without cutting it apart. I usually only use them when I'm tight on space.
 
Cow said:
I don't care for those box adapters, you can't take your conduit back out of the box without cutting it apart. I usually only use them when I'm tight on space.
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They don't keep water out as well as a male adapter and standard locknut will either.
 
Volta said:
Yup, as Acrwc mentioned, if the wire in the 2" is larger than a #6, you'll need to splice it.
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But not in the 1-1/4"?:-?

Conductors larger than #6 have to be spliced if entering an enclosure?:confused:

OP did not mention what was being pulled in the raceways, he asked about installing a PVC connector in the top side of an enclosure. He could have only 3 #14's in these raceways, may be overkill, but nothing wrong with it code wise.
 
kwired said:
But not in the 1-1/4"?:-?

Conductors larger than #6 have to be spliced if entering an enclosure?:confused:

OP did not mention what was being pulled in the raceways, he asked about installing a PVC connector in the top side of an enclosure. He could have only 3 #14's in these raceways, may be overkill, but nothing wrong with it code wise.
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Sure, we don't know, but if larger than #6, for a straight pull 314.28(A)(1): 1.25" x 8 = 12", ok.
2" x 8 = 16", the box is too small.

For splices 314.28(A)(2): 1.25" x 6 = 7.5", ok.
2" x 6 =12", ok.

So if the conductor(s) in the 2" raceway are #4 or larger, they must be spliced, and cannot be pulled straight through.
 
Taken from UL's 651 Schedule 40 and 80 Rigid PVC Conduit and Fittings

1.10 Rigid PVC conduit and fittings covered in these requirements are intended to be joined to each other and to rigid PVC boxes, conduit bodies, and fittings in the field by means of a cement that is or contains a solvent for polyvinyl chloride.

1.17 Externally-threaded adapters (also referred to as terminal adapters) covered by these requirements are fittings intended for joining a length of rigid PVC conduit or elbow or other bend to:

a) The knockout area of a metal box with a metal locknut,
b) A threaded metal hub or fitting on a metal box,
c) A threaded hub on a phenolic box, or
d) A knockout in a phenolic box.

So, per UL, we can connect PVC conduit or fittings to a PVC box with cement, or to a metal hub in this wet location. Sealing locknuts and washers are for metal conduit, unless otherwise listed on the carton.
 
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