Entering into a 3R enclosure with EMT on the top of the enclosure

Status
Not open for further replies.

MRTEASOLAR

New member
Location
Merced, CA, USA
Greetings to all,

I would like input from you all relating to entering a 3R gutter from above using only a Raintight compression connector. In your experience, is it sufficient to trust the gasket? It appears to me the gasket distorts upon tightening and my concern is water entering the enclosure. Is a meyers hub, then the raintight compression connector a good combination? Or is using a washer in conjunction with the gasket an acceptable added measure?

Is there any links to UL stating acceptable entrance to 3R enclosures from above?

Cheers!
 

thegreathoo

Member
Location
Tampa
Yes it is sufficient in my experience, you are using a listed raintight connector. There is no issue with the gasket or the gasket being on only one side of the enclosure. That is all that is needed, one gasket on a listed raintight connector. Obviously it comes down to installation whether it will hold, obviously your hole has to be covered and the gasket should seal well. If it does not, then you need a different connector or another gasket on the other side of the knockout.
 
Greetings to all,

I would like input from you all relating to entering a 3R gutter from above using only a Raintight compression connector. In your experience, is it sufficient to trust the gasket? It appears to me the gasket distorts upon tightening and my concern is water entering the enclosure. Is a meyers hub, then the raintight compression connector a good combination? Or is using a washer in conjunction with the gasket an acceptable added measure?

Is there any links to UL stating acceptable entrance to 3R enclosures from above?

Cheers!

IMO there is no good way to come into the top of a 3R cabinet with EMT. I think the RT connector is perfectly acceptable code wise, but in practice the gasket distorts so you cant tighten up at all and I hate that. I think a myers hub is technically for RMC or IMC and not listed for use with the straight threads on an EMT connector. If code were not an issue, I would throw away the gasket and just use the RT connector without it - who cares if there are a few drips of water in the trough?
 

Dennis Alwon

Moderator
Staff member
Location
Chapel Hill, NC
Occupation
Retired Electrical Contractor
You can use a wp locknut in conjunction with the hub

lns-50.jpg
 

gadfly56

Senior Member
Location
New Jersey
Occupation
Professional Engineer, Fire & Life Safety
Greetings to all,

I would like input from you all relating to entering a 3R gutter from above using only a Raintight compression connector. In your experience, is it sufficient to trust the gasket? It appears to me the gasket distorts upon tightening and my concern is water entering the enclosure. Is a meyers hub, then the raintight compression connector a good combination? Or is using a washer in conjunction with the gasket an acceptable added measure?

Is there any links to UL stating acceptable entrance to 3R enclosures from above?

Cheers!

Is it foolish to ask if there isn't some way you can come in from underneath?
 

templdl

Senior Member
Location
Wisconsin
Greetings to all,

I would like input from you all relating to entering a 3R gutter from above using only a Raintight compression connector. In your experience, is it sufficient to trust the gasket? It appears to me the gasket distorts upon tightening and my concern is water entering the enclosure. Is a meyers hub, then the raintight compression connector a good combination? Or is using a washer in conjunction with the gasket an acceptable added measure?

Is there any links to UL stating acceptable entrance to 3R enclosures from above?

Cheers!
If I have understood your question correctly have you consideere a Raintight hub as available (Myers Hub?) that are UL listed that must be installed with 4 screws and a gasket securing it in place.
As far as the use of EMT is concerned you will have to review the specs for the hub for its use with conduit. There may be a question regarding the use of EMT in an environment where a NEMA 3r enclosure is required though.
 

KDough

Member
Location
San Jose, CA
Occupation
Electrician 42 yrs / Electrical Inspector 4yrs
This is a very interesting question. I have asked this question myself and being old school you just did not enter the top of a 3R enclosure without a Myers Hub. But that was before RainTight connectors. Oh sure we used to call them raintight but they actually were not. They were just compression connectors. Now that they came out with real raintight connectors that are listed and approved to keep rain out of an enclosure it is perfectly acceptable to use a listed raintight connector to enter the top of a 3R enclosure. But as with anything else the installer has to install the listed part properly in order for is to work as it should.

If you install these raintight connectors the way you normally install a connector you will end up with a deformed gasket and they will fail. To install them properly you must tighten with the locknut and not the connector body. In doing so the gasket will stay flat with no deformation and will work as intended
 

wwhitney

Senior Member
Location
Berkeley, CA
Occupation
Retired
Bridgeport has a raintight EMT x RMC nipple connector for use in a threaded entry. I assume it could be used in a Myers hub.


Cheers, Wayne
 

tom baker

First Chief Moderator
Staff member
Well, once that fitting is available, the AHJs know about it, we will be on notice. When I say available, just because it made does not mean I can get one from my supply house.
 

KDough

Member
Location
San Jose, CA
Occupation
Electrician 42 yrs / Electrical Inspector 4yrs
No, These listed raintight connectors are readily available even Home Depot carries them. They have been out for at least ten years +. Bridgeport, Raco, T&B, Arlington .... just about every manufacturer make a listed raintight EMT connector now
 

KDough

Member
Location
San Jose, CA
Occupation
Electrician 42 yrs / Electrical Inspector 4yrs
What they did was take the old style compression connector added the gasket between the connector and the can or gutter and then added a second tapered sealing ring inside that actually pushes in between the EMT and the inside of the connector body to seal all the way around the conduit. Brilliant.
 

wwhitney

Senior Member
Location
Berkeley, CA
Occupation
Retired
Well, once that fitting is available, the AHJs know about it, we will be on notice. When I say available, just because it made does not mean I can get one from my supply house.
Bridgeport only shows them in 1/2", 3/4", and 1", so there's still an issue with larger sizes.

Cheers, Wayne
 

hillbilly1

Senior Member
Location
North Georgia mountains
Occupation
Owner/electrical contractor
Bridgeport only shows them in 1/2", 3/4", and 1", so there's still an issue with larger sizes.

Cheers, Wayne
I used some 3” last month, don’t remember the brand. First I had seen of them. Old time compression fittings had raintite on the box, whether they were listed or not, I don’t know, but I do know for a fact the manufacturer said they were raintite.
 

wwhitney

Senior Member
Location
Berkeley, CA
Occupation
Retired
I used some 3” last month, don’t remember the brand. First I had seen of them. Old time compression fittings had raintite on the box, whether they were listed or not, I don’t know, but I do know for a fact the manufacturer said they were raintite.
3" raintight EMT compression to rigid (male or female) transition couplings? That's what I posted about.

Cheers, Wayne
 

Little Bill

Moderator
Staff member
Location
Tennessee NEC:2017
Occupation
Semi-Retired Electrician
This thread is 6 years old and threads over a year old are normally closed. If anyone wishes to continue the subject, you can start a new thread.
 
Status
Not open for further replies.
Top