PVC Male Adapter to hub

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tonybolin

Member
Hello

My inspector informed me that PVC male adapters are not rated to thread into hubs.

The print specified PVC mast, where do I find this rating
 

kwired

Electron manager
Location
NE Nebraska
Hello

My inspector informed me that PVC male adapters are not rated to thread into hubs.

The print specified PVC mast, where do I find this rating

I believe you need to look at UL white book. This topic comes up time to time on this forum and it has been mentioned many times that typical myers hubs or other hubs of the bolt on type are intended for tapered threaded raceways only. This generally limits their use to RMC and IMC that is threaded and not the use of raceway fittings that typically have non tapered threads.

I do believe I have seen PVC "cement in" meter socket hubs in catalogs but must admit I can't ever recall seeing or using one. Most inspectors are either not aware or not enforcing this, or have accepted some reason to allow it, as it is seen a lot.
 

infinity

Moderator
Staff member
Location
New Jersey
Occupation
Journeyman Electrician
None of these- PVC terminal adapters, EMT connectors and SE cable connectors are listed for use in hubs. So how is it that 90% of all services around here use one of those three wiring methods? You can thank Mark Ode from UL. He wrote an article not too long ago about how only IMC and RMC are code complaint in hubs. Seems like the guys who wrote the standard are to blame when you violate just about every residential service out there. :rant:

Here's the article, guess your EI read it. ;)

http://www.ecmag.com/?articleID=11585&fa=article
 

kwired

Electron manager
Location
NE Nebraska
None of these- PVC terminal adapters, EMT connectors and SE cable connectors are listed for use in hubs. So how is it that 90% of all services around here use one of those three wiring methods? You can thank Mark Ode from UL. He wrote an article not too long ago about how only IMC and RMC are code complaint in hubs. Seems like the guys who wrote the standard are to blame when you violate just about every residential service out there. :rant:

Here's the article, guess your EI read it. ;)

http://www.ecmag.com/?articleID=11585&fa=article

FWIW I will give my opinion.

When it comes to water tightness the inside of the raceway is also considered a wet location. What difference does it make if you get an occasional drop of water through those threads when you may get a few tablespoons of condensation inside the raceway every night when conditions are right for it? This has been my opinion about the stupid raintight EMT fittings they came out with a few years ago. Before those I always used EMT fitting in Myers hubs. You know how many of these EMT fittings I have installed and come back to within 1 year and the gasket has deteriorated from sunlight and the fitting leaks more than the old standard compression fitting did? Not to mention you about have to take the fitting completely apart to successfully insert the raceway most of the time. Those things are a joke.

Next is the reliability of equipment grounding. If you turn the fitting in until it is wrench tight why should there be a bonding issue? How many times do we thread RMC or IMC into a fitting until it is tight and then have to back it off to get the right deflection of a bend? Whether acceptable or not it is done, and likely is not as good of a bond as an EMT fitting that is tight in the hub.
 

infinity

Moderator
Staff member
Location
New Jersey
Occupation
Journeyman Electrician
FWIW I will give my opinion.

When it comes to water tightness the inside of the raceway is also considered a wet location. What difference does it make if you get an occasional drop of water through those threads when you may get a few tablespoons of condensation inside the raceway every night when conditions are right for it? This has been my opinion about the stupid raintight EMT fittings they came out with a few years ago. Before those I always used EMT fitting in Myers hubs. You know how many of these EMT fittings I have installed and come back to within 1 year and the gasket has deteriorated from sunlight and the fitting leaks more than the old standard compression fitting did? Not to mention you about have to take the fitting completely apart to successfully insert the raceway most of the time. Those things are a joke.

Next is the reliability of equipment grounding. If you turn the fitting in until it is wrench tight why should there be a bonding issue? How many times do we thread RMC or IMC into a fitting until it is tight and then have to back it off to get the right deflection of a bend? Whether acceptable or not it is done, and likely is not as good of a bond as an EMT fitting that is tight in the hub.

I agree. I find it hard to swallow that UL would write a standard that doesn't include millions of proven installations. :rant:
 
FWIW I will give my opinion.

When it comes to water tightness the inside of the raceway is also considered a wet location. What difference does it make if you get an occasional drop of water through those threads when you may get a few tablespoons of condensation inside the raceway every night when conditions are right for it? This has been my opinion about the stupid raintight EMT fittings they came out with a few years ago. Before those I always used EMT fitting in Myers hubs. You know how many of these EMT fittings I have installed and come back to within 1 year and the gasket has deteriorated from sunlight and the fitting leaks more than the old standard compression fitting did? Not to mention you about have to take the fitting completely apart to successfully insert the raceway most of the time. Those things are a joke.

Next is the reliability of equipment grounding. If you turn the fitting in until it is wrench tight why should there be a bonding issue? How many times do we thread RMC or IMC into a fitting until it is tight and then have to back it off to get the right deflection of a bend? Whether acceptable or not it is done, and likely is not as good of a bond as an EMT fitting that is tight in the hub.
:thumbsup:
 

GerryB

Senior Member
Hello

My inspector informed me that PVC male adapters are not rated to thread into hubs.

The print specified PVC mast, where do I find this rating

You said he informed you. Do you mean when you took out the permit and before you actually did the job, or does he reject every service he inspects?
 

texie

Senior Member
Location
Fort Collins, Colorado
Occupation
Electrician, Contractor, Inspector
In the olden days we did not have sealing washers, so using a myers hub was standard practice for this. The problem I have with sealing washers is they are so cheesy they do a poor job. You often see them all mangled and squished out. How is that better than a non compliant hub and PVC MA? One of those mysteries of the trade and the listing folks that don't know what it is like in the field.
 

Dennis Alwon

Moderator
Staff member
Location
Chapel Hill, NC
Occupation
Retired Electrical Contractor
I spoke with a UL guy about this and his opinion was that it would be water tight however the manufacturers only paid to have it tested with rigid for some reason.
 
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