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Listed Rain Tight Hubs and Fittings

13115 Views 44 Replies 17 Participants Last post by  donl
Recently our local AHJ has decided the use of Myers type hubs and the Factory supplied hub on the top of panels and metering devices are only listed for GRC or IMC. In addition, we are being informed any field penetrations into the top of any rain tight enclosure is also in violation of the listing for the enclosures.

For my entire career in the electrical industry (+27 years) it has been common practice to install a listed rain tight EMT connector or PVC terminal adapter into these hubs then install EMT or PVC in-lieu-of GRC or IMC where the installation allows for the conduit type. Additionally, it has also been common practice to knock out an opening, install a threaded rain tight hub and exit the enclosure through the top with which ever raceway method you choose assuming it is installed per the NEC.

Installing GRC or IMC in some instances will almost be impossible for the type of work we do. I would like to hear others thoughts, ideas, and or suggestions. Product manufacturers are definitely encouraged to give me your feedback and suggestions.
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Recently our local AHJ has decided the use of Myers type hubs and the Factory supplied hub on the top of panels and metering devices are only listed for GRC or IMC. In addition, we are being informed any field penetrations into the top of any rain tight enclosure is also in violation of the listing for the enclosures.

For my entire career in the electrical industry (+27 years) it has been common practice to install a listed rain tight EMT connector or PVC terminal adapter into these hubs then install EMT or PVC in-lieu-of GRC or IMC where the installation allows for the conduit type. Additionally, it has also been common practice to knock out an opening, install a threaded rain tight hub and exit the enclosure through the top with which ever raceway method you choose assuming it is installed per the NEC.

Installing GRC or IMC in some instances will almost be impossible for the type of work we do. I would like to hear others thoughts, ideas, and or suggestions. Product manufacturers are definitely encouraged to give me your feedback and suggestions.
NOPE.

Install a nipple. Then transition to PVC -- if that's what's best.

He's busting your %$#@ over the fact that a Meyers hub is listed for GRC/IMC compression threads.

As for the rest, it sounds like the AHJ does not know his business.

All across America, top side penetrations are common as dust.

BTW, this very topic has been recently beaten to death at ET.

Scroll through the back threads. You won't have to go far.
 

· Old Grumpy Bastard
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Welcome aboard @DMack!

Only things I have seen approved for entering the top of rain tight enclosures are Meyers hubs, conduit hub, or pvc hubs.

Many guys use a rigid nipple and a pvc female adapter to connect to that nipple.
 

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This is a ****ing stupid bullcrap issue created at Mike Holts and they should be embarrassed.
When it comes right down to it it should have been listed with the thread pitch as they are the same. The people in the know are way to smart for that though. This is why you need to get involved in your local town and get on a board or two, so you can mention how ****ing stupid this type of stuff is.
 

· Small Potatoes
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We've been doing the ridged nipple and female PVC adapter set up for several years since the first time we got knocked down for installing a PVC TA into a hub.

It looks like chit, but meets the code.

I think I'll develope a plastic hub and get it listed for PVC. :brows:
 

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We've been doing the ridged nipple and female PVC adapter set up for several years since the first time we got knocked down for installing a PVC TA into a hub.

It looks like chit, but meets the code.

I think I'll develope a plastic hub and get it listed for PVC. :brows:
Are you talking about coming out of the top of a meter with a meter hub as well? If so, do you have pictures?
 

· Small Potatoes
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Are you talking about coming out of the top of a meter with a meter hub as well? If so, do you have pictures?
The hub on top of a meter pan that screwas on with four screws. We use a 6 inch 2" ridged nipple and then a 2 inch femal PVC adapter.

I don't have any pictures, but next time we do one I'll try to get some.

We did a 40KW generator a while back and my guys used a NEMA 3 trough, punched 2 in. holes in the top and used Meyers hubs. I went out to the job and had a feeling it was going to be a problem. Sure enough the inspector said something about them not being approved for the application, but he let go.

Edit: Thinking further about this, I think my guy used the hubs you use for meter pans on the trough. Not Meyers hubs.
 

· Can't Remember
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The idea being if a plastic ta can be screwed into a hub then how about the SE connector, straight threads on each not tapered. Looking for a solution for both. In much of what I do, the utility owns the meter socket up all the way to the pole, but it would be nice not to have to deal with this at the next inspection.
 

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The idea being if a plastic ta can be screwed into a hub then how about the SE connector, straight threads on each not tapered. Looking for a solution for both. In much of what I do, the utility owns the meter socket up all the way to the pole, but it would be nice not to have to deal with this at the next inspection.
I see.

The PVC meter hubs in Canada don't have threads, you glue the pipe directly into it.

Would they ever make a hub with straight threads? It would be hard to tell apart and it wouldn't work for rigid pipe.
 

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These kinds of violations seem to come down when inspectors attend seminars or code update classes.

Something that may have been fine for years, is now a glaring violation because someone looked up the listing and then preached about it in a code update class.
Yup.

It pisses me off that I can't use strong metal 2-hole straps to support my PVC risers. Instead, I have to use soft, brittle, easily breakable PVC straps which after a few years in the sun will crack.

But the listing... :rolleyes:
 
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