Nema Rating/schedule 40 PVC

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kec

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Location
CT
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Electrical Contractor
What is the NEMA rating of schedule 40 Pvc conduit. Can't seem to find a definitive answer.

This question is in regards to conduit entering a fire pump controller. Conduit has to be NEMA -2
 
The fire pump controller as I'm told is a NEMA rated cabinet.
I installed schedule 40 PVC to supply power to and to fire pump. Fire supression company told me i couldn't use PVC because it has to be NEMA -2
 
If by that you mean NEMA environmental specifications, as in NEMA 1, 3R, 4, 12 etc., the NEMA 2 is basically NEMA 1 + it is "Drip Tight", meaning FALLING (but not wind driven, hose directed, sprayed etc.) drops of water will not enter and build up inside of electrical equipment.

As a general rule, CONDUIT does not have a NEMA rating, but how it enters and exits enclosures would. If you glue PVC pipe and use proper fittings, yes, it would exceed NEMA 2 environmental specs.

Ps (after seeing your post):
Technically, your fire suppression company was not correct. The CONDUIT is not going to have a NEMA rating, just the FITTINGS for entering the enclosure. We don't know how you did that though. If you used sealing lock nuts or came in through Meyers hubs, that would exceed NEMA 2 requirements. Whether an AJH has a problem with that is another matter. TECHNICALLY, Meyers hubs are listed for use with GRC conduit, as are most sealing lock nuts. But threaded male adapters for PVC are using the EXACT same threads as GRC. I personally have never had an AHJ question it, but I've heard stories of nasty ones that do.

Case in point:
 
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If by that you mean NEMA environmental specifications, as in NEMA 1, 3R, 4, 12 etc., the NEMA 2 is basically NEMA 1 + it is "Drip Tight", meaning FALLING (but not wind driven, hose directed, sprayed etc.) drops of water will not enter and build up inside of electrical equipment.

As a general rule, CONDUIT does not have a NEMA rating, but how it enters and exits enclosures would. If you glue PVC pipe and use proper fittings, yes, it would exceed NEMA 2 environmental specs.
I agree and this controller is in a weatherproof building so no rain,water, dust etc, will not enter the cabinet.
 
One problem with Schedule 40 is it is not listed for physical protection whereas schedule 80 is. With that said read through 695.6 and see if you meet all the requirements.

Roger
 
I did not use a Meyers hub because the only place to enter this cabinet is from underneath.
Therefore I saw no need to use one. I guess if I use a sealing washer or lock nut then it should comply.
 
I did not use a Meyers hub because the only place to enter this cabinet is from underneath.
Therefore I saw no need to use one. I guess if I use a sealing washer or lock nut then it should comply.
Entries in bottom or in sides below live components don't effect watertightness for falling water, can be an issue with pressurized spray or wind driven rain or similar though.

That said some inspectors are pretty anal about a set screw type fitting in bottom of an enclosure in such situations though logically it really shouldn't matter.
 
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