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Repairing NEMA 4x Penetrations

Repairing NEMA 4x Penetrations

Repairing NEMA 4x Penetrations

(OP)
I'm trying to find the best way to patch a hole in a NEMA 4x panel box.  In order to mount a temp stat sensor onto the box we were required to run the wires into the box.  The Stat sensor is an open device and a gasket behind the stat would not properly shield the hole from the outside environment.  What would be the best way to seal the hole to maintain the NEMA 4x rating?

RE: Repairing NEMA 4x Penetrations

What does the stat look like? Does it have a shaft or cord? If so, you can use a "sealing cord grip" or "cable gland". It is a fitting that installs through a standard conduit entry hole and has a sealing gromment (grommet?) that you buy to fit the shaft diameter. When you tighten the outside compression nut, that gromment compresses around whatever is penetrating the enclosure wall. Just make sure that whatever one you buy says that it SPECIFICALLY meets UL Type 4 or 4X, otherwise you cannot maintain the enclosure integrity.

As an example, looks like this:



Interesting side note, spell check seems to think that "gromment" is not a word, yet I have seen it spelled that way my entire career, although I guess I have not had to type that word since the advent of spell checkers...  


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RE: Repairing NEMA 4x Penetrations

I know now. I posted in the "Engineering Language/Grammar" forum and done been edumacated more gooder now.


"If I had eight hours to chop down a tree, I'd spend six sharpening my axe." -- Abraham Lincoln  
For the best use of Eng-Tips, please click here -> FAQ731-376: Eng-Tips.com Forum Policies  

RE: Repairing NEMA 4x Penetrations

jraef is right: the grommet does not maintain 4x integrity.
Cable must be connected through a liquid tight conduit fitting using the appropriate conduit type to maintain the NEMA 4X rating.
That means in order to maintain NEMA 4X rating one has to connect the cable by means of a flexible liquid tight conduit or galvanized rigid steel conduit c/w suitable fitting.
See:
http://www.o-zgedney.com
There are more other suppliers as Thomas&Betts, Crouse Hinds and others.

RE: Repairing NEMA 4x Penetrations

brentna,
What jraef showed you are "cable glands". You could specify for explosion proof cable/ deluge proof glands to solve your NEMA 4X-related penetrations.
My 2¢

RE: Repairing NEMA 4x Penetrations

"I'm trying to find the best way to patch a hole in a NEMA 4x panel box."
"The Stat sensor is an open device and a gasket behind the stat would not properly shield the hole from the outside environment"

I am not quite sure of your question, but are you trying to "fix/patch/repair" a NEMA 4X rated panel box?

RE: Repairing NEMA 4x Penetrations

(OP)
Sorry Raptor i worded it poorly.  I needed to Plug the whole with the wires in it.  We are looking at either using a cable gland or having the equipment suppliers provide NEMA 4x stats.  Then the problem can be fixed with a simple gasket that should come with the stat.  Thanks for all your help.

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