RGS conduit into NEMA box / Disconnect

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Cjmccarthy

Cjmccarthy

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Is this the correct way to install RGS conduits into a Disconnect or NEME box? I have never seen it done this way, the locking nuts are always on the inside and on the outside it has the gasket. I am trying to find the NEC code that talks about it.

as always, thank you guys for your help.
 

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That looks like one method of entering a rain-tight enclosure althiugh, if those are entering the bottom of the enclosure, there would be no need for the gaskets.
 
augie47 said:
That looks like one method of entering a rain-tight enclosure althiugh, if those are entering the bottom of the enclosure, there would be no need for the gaskets.
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SO they don't have to have a gasket on the outside going in? this is out in the elements.
 
See 312.2, below the live parts nothing specific is required. Above you would have to use a fitting or gasket that would be for wet locations.

For enclosures in wet locations,
raceways or cables entering above the level of uninsulated
live parts shall use fittings listed for wet locations.
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roger said:
See 312.2, below the live parts nothing specific is required. Above you would have to use a fitting or gasket that would be for wet locations.
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would wet locations go for anything entering the side?
 

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Has nothing to do with your question but it appears the conduit going out the side is in violation of 250.64 assuming that is routed to a grounding electrode.

As far as the "un-needed" gaskets, I have seen situations where, for simplicity's sake, contractors have instructed employees to "use gaskets anytime it['s outdoors" rather than explain Code. There is no harm in having them there.
 
augie47 said:
Has nothing to do with your question but it appears the conduit going out the side is in violation of 250.64 assuming that is routed to a grounding electrode.

As far as the "un-needed" gaskets, I have seen situations where, for simplicity's sake, contractors have instructed employees to "use gaskets anytime it['s outdoors" rather than explain Code. There is no harm in having them there.
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This contractor is, lets say difficult. it is routed to a ground rod, what part of 250.64 does it violate?
 
I know the other posters know this, but it isn't clear in the thread. All the comments refer to a NEMA 3R box, cabinet or cutout. If the enclosure is installed as a NEMA 3 application, it does require gasketing on all of the penetrations. The OP doesn't clarify.
 
Cjmccarthy said:
SO they don't have to have a gasket on the outside going in? this is out in the elements.
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For 3R rating no.

For a true 3 or 4 or even higher rating number yes you still would need gasket or whatever applies to the rating.

3R is your raintight items, can take water falling from above and up to a certain angle, and is designed to drain any water that would happen to get inside. N3, N4 and higher are all totally closed up with the ability to withstand other details that go with the rating.
 
kwired said:
For 3R rating no.

For a true 3 or 4 or even higher rating number yes you still would need gasket or whatever applies to the rating.

3R is your raintight items, can take water falling from above and up to a certain angle, and is designed to drain any water that would happen to get inside. N3, N4 and higher are all totally closed up with the ability to withstand other details that go with the rating.
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so far, this is what I found for a spec.
639-3.5 Service Disconnect:
639-3.5.1 Enclosure (Cabinet): Use an enclosure conforming to National
Electrical Manufacturers Association (NEMA) Standards for Type 3R, Type 3S or Type 4, made
of galvanized steel, aluminum, stainless steel or other materials approved by the Engineer. Ensure that the inside
dimensions meet NEC requirements.
There is writing on the standard plans for NEMA 3R or Better.
 
A 3R box is designed to drain condensation out the bottom so having a gasket or sealing lock ring on the bottom is pointless. It's not an airtight or watertight box, moisture is going to get in, but it's not going to drain upwards through the bottom in defiance of gravity. In fact any gaps around those locking rings will help it drain better.

As a matter of practice I always use a sealing connector or lock ring on the top and sides although strictly speaking you only have to if it's above live parts as mentioned in post #4.

If you have an enclosure that needed to meet a higher NEMA standard, you'd need a sealing connector method. This would be rare, like if required by the manufacturer of the boxes contents. It wouldn't be required directly by the code per se.
 
jaggedben said:
A 3R box is designed to drain condensation out the bottom so having a gasket or sealing lock ring on the bottom is pointless. It's not an airtight or watertight box, moisture is going to get in, but it's not going to drain upwards through the bottom in defiance of gravity. In fact any gaps around those locking rings will help it drain better.

As a matter of practice I always use a sealing connector or lock ring on the top and sides although strictly speaking you only have to if it's above live parts as mentioned in post #4.

If you have an enclosure that needed to meet a higher NEMA standard, you'd need a sealing connector method. This would be rare, like if required by the manufacturer of the boxes contents. It wouldn't be required directly by the code per se.
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I just found in the plans ( Fusible Disconnect Switch, 120V/1P/30A, with 30A fuse NEMA-4X ) would that require a sealing connector?
 
NEMA4X is one of the enclosures that would require sealing such as that shown as spelled out in NEC 312.2, as mentioned.
(From the wording in 312.2 sealing would not be required on the conduits entries into the bottom of the switch but there is no harm in sealing being there.)
 
Maintaining the NEMA 4X on that enclosure might require sealing lock rings. That's a job spec, not directly required by code.

The differences between NEMA 3R and NEMA 4X are:
1) NEMA 4X is supposed to keep out dust
2) NEMA 4X provides a greater degree of corrosion resistance

(1) seems like overkill to me for a fusible disconnect. In fact I think the NEMA 4X spec is a mistake: I'd much rather have an enclosure that drains water than one that keeps dust out, because with NEMA 4X if water somehow gets in then it won't necessarily leave. That's just my opinion and you have a job spec.
(2) does not seem to be affected by whether or not those lock rings are sealing lock rings.
I would think the NEMA 4X rating (the dust tight part) could be maintained by sealing lock rings on either the inside or the outside of the box. (Inside would be a lot easier.) Just my judgment.

If the intention of specifying NEMA 4X was merely to have a stainless box (looks like it is) and not so much to keep dust out, I would leave the installation as is so it drains.
 
jaggedben said:
Maintaining the NEMA 4X on that enclosure might require sealing lock rings. That's a job spec, not directly required by code.

The differences between NEMA 3R and NEMA 4X are:
1) NEMA 4X is supposed to keep out dust
2) NEMA 4X provides a greater degree of corrosion resistance

(1) seems like overkill to me for a fusible disconnect. In fact I think the NEMA 4X spec is a mistake: I'd much rather have an enclosure that drains water than one that keeps dust out, because with NEMA 4X if water somehow gets in then it won't necessarily leave. That's just my opinion and you have a job spec.
(2) does not seem to be affected by whether or not those lock rings are sealing lock rings.
I would think the NEMA 4X rating (the dust tight part) could be maintained by sealing lock rings on either the inside or the outside of the box. (Inside would be a lot easier.) Just my judgment.

If the intention of specifying NEMA 4X was merely to have a stainless box (looks like it is) and not so much to keep dust out, I would leave the installation as is so it drains.
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Makes sense, I would still want the one on the side to have the sealing lock ring. but it makes sense on the bottom rings to leave them for possible drainage.
 
Cjmccarthy said:
Is this the correct way to install RGS conduits into a Disconnect or NEME box? I have never seen it done this way, the locking nuts are always on the inside and on the outside it has the gasket. I am trying to find the NEC code that talks about it.

as always, thank you guys for your help.
Click to expand...
What is RGS
 
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