Pvc into top of nema 3 enclosure

[electrofelon]

Is only the male adapter tapered? Most females look straight to me but you never know.

I dont really like the tapered/non tapered argument. Although it seems intuitive, do you have any evidence that mixing tapered and non tapered is the reason? I have never seen that stated by any authority. Note RGS couplings are non tapered.

 

[Joethemechanic]

342.28 Reaming and Threading
All cut ends shall be reamed or otherwise finished to remove rough edges. Where conduit is threaded in the field, a standard cutting die with a taper of 1 in 16 (3/4 in. taper per foot) shall be used.
Informational Note: See ANSI/ASME B1.20.1-2013, Standard for Pipe Threads, General Purpose (Inch).

 

[letgomywago]

I think it's another example of how out of touch most of the codes and standards people are, that it didn't occur to anybody that people will want to put PVC TA's into these things

Tell arlington you want it and maybe they'll get it listed. They already have a one box with metal gem box in it and a romex connector good for 13 small romexes.

 

[letgomywago]

I got two PL due for review on September 7. I think I will write two more; one to outlawing rigid use underground, one mandating PVC use only underground. I can't count how many times I have found rigid rusted out completely underground. Plus, when you use PVC, you have to pull a green grounding wire. That will reduce the impedance and make it a better installation.

The rigid 6inches underground to feed a shed in a dry desert location I feel is in now way dangerous.

 

[don_resqcapt19]

Tell arlington you want it and maybe they'll get it listed. They already have a one box with metal gem box in it and a romex connector good for 13 small romexes.

Not sure there is anything in the product standard that would permit the conduit hub to be listed for use with PVC. I think this is a case where the product standard would have to be changed first.

 

[electrofelon]

Not sure there is anything in the product standard that would permit the conduit hub to be listed for use with PVC. I think this is a case where the product standard would have to be changed first.

So any idea who's idea it was to create a product standard that only allowed RMC? Maybe this goes back a long ways before PVC was used much?

 

[wwhitney]

Not sure there is anything in the product standard that would permit the conduit hub to be listed for use with PVC. I think this is a case where the product standard would have to be changed first.

Again, if the PVC male adapter is listed to be used with the threaded metal hub, why does the threaded metal hub need to be listed for the PVC male adapter?

An analogous situation would be classified circuit breakers. A panelboard will list certain breakers that can be used with it, but if a third party tests and lists their own breaker to used with that panelboard, you can use them, even though the panelboard hasn't listed those third party breakers.

So as the PVC male adapter has been listed to be used with threaded metal hubs, that suffices.

Cheers, Wayne

 

[electrofelon]

Again, if the PVC male adapter is listed to be used with the threaded metal hub, why does the threaded metal hub need to be listed for the PVC male adapter?

An analogous situation would be classified circuit breakers. A panelboard will list certain breakers that can be used with it, but if a third party tests and lists their own breaker to used with that panelboard, you can use them, even though the panelboard hasn't listed those third party breakers.

So as the PVC male adapter has been listed to be used with threaded metal hubs, that suffices.

Cheers, Wayne

I think I agree with you here, as long as it was a case of them just not being investigated for the use. If they had been investigated for the use but denied for some reason, then we would have to ask why there is a conflict where one investigation found them okay but the other did not.

 

[wwhitney]

I think I agree with you here, as long as it was a case of them just not being investigated for the use.

That is literally what the quoted language in post #28 from the DWTT UL category information says.

Cheers, Wayne

 

[don_resqcapt19]

Again, if the PVC male adapter is listed to be used with the threaded metal hub, why does the threaded metal hub need to be listed for the PVC male adapter?

An analogous situation would be classified circuit breakers. A panelboard will list certain breakers that can be used with it, but if a third party tests and lists their own breaker to used with that panelboard, you can use them, even though the panelboard hasn't listed those third party breakers.

So as the PVC male adapter has been listed to be used with threaded metal hubs, that suffices.

Cheers, Wayne

Yet the UL Guide Information for the hub says otherwise and the guide information is a 110.3(B) listing and labeling instruction. Where there is a conflict between listing and labeling instructions, it becomes a 90.4(B) issue and only YOUR AHJ knows the answer.

 

[don_resqcapt19]

I think I agree with you here, as long as it was a case of them just not being investigated for the use. If they had been investigated for the use but denied for some reason, then we would have to ask why there is a conflict where one investigation found them okay but the other did not.

They have not been investigated (tested) for the use because there is no provision in the listing standard that provides for that investigation.

 

[don_resqcapt19]

So any idea who's idea it was to create a product standard that only allowed RMC? Maybe this goes back a long ways before PVC was used much?

Maybe no one has submitted a proposal to make a change in the listing standard. As currently written the hubs can't even be used with IMC even though the threads are identical to those of RMC.
There is a process to submit proposals to change listing standards. I have not tried it, but it does not appear to be near as easy as submitting a PI to change the NEC.

 

[wwhitney]

Yet the UL Guide Information for the hub says otherwise and the guide information is a 110.3(B) listing and labeling instruction.

The phrase "has only been investigated with X" does not mean the same as "may only be used with X." The "has only been investigated with X" language is agnostic on other uses. It just says that manufacturer of the hub has only done certain testing in getting the hub listed.

So I don't see any 110.3(B) violation. However, 110.2 does require that all the equipment be approved by the AHJ. An AHJ could reasonably choose not to approve a part being used in a way that never been investigated.

But the listing standard for the PVC male adapter you quoted says that they are intended for use with threaded metal hubs. So the combination has been considered by the listing standard for the PVC male adapter. That's a good reason to approve it under 110.2.

If you contrast this situation with say an EMT connector, I'm guessing its listing standard doesn't say anything about being intended for use with threaded metal hubs. In that case the combination has not been considered as part of the listing of either part, so the idea of not approving the combination makes more sense.

Cheers, Wayne

 

[electrofelon]

If you contrast this situation with say an EMT connector....


Cheers, Wayne

Of course it would be idea to take care of the whole mess, to include other components such as EMT connectors, bell boxes, etc....

 

[don_resqcapt19]

The phrase "has only been investigated with X" does not mean the same as "may only be used with X." The "has only been investigated with X" language is agnostic on other uses. It just says that manufacturer of the hub has only done certain testing in getting the hub listed.

So I don't see any 110.3(B) violation. However, 110.2 does require that all the equipment be approved by the AHJ. An AHJ could reasonably choose not to approve a part being used in a way that never been investigated.

But the listing standard for the PVC male adapter you quoted says that they are intended for use with threaded metal hubs. So the combination has been considered by the listing standard for the PVC male adapter. That's a good reason to approve it under 110.2.

If you contrast this situation with say an EMT connector, I'm guessing its listing standard doesn't say anything about being intended for use with threaded metal hubs. In that case the combination has not been considered as part of the listing of either part, so the idea of not approving the combination makes more sense.

Cheers, Wayne

That listing standard says pretty much the same as the one for the conduit hubs....the connector has only been investigated for use with a locknut and has not been investigated for use in fittings having female threads.
The same as LFMC connectors....where at least 95% of the ones I have installed or my crew has installed have been threaded into fittings or equipment having female threads.
For the most part things like this are just ignored by the AHJ, but when they are not, it is totally up to the AHJ.

 

[wwhitney]

For the most part things like this are just ignored by the AHJ, but when they are not, it is totally up to the AHJ.

Agreed when the listing standards for both sides of the connection are silent on the combination.

Disagree in cases like the OP, where the listing standard for one side of the connection explicitly has considered the combination. (Thanks for digging up that info from the listing standard.)

Cheers, Wayne

 

[tortuga]

Maybe no one has submitted a proposal to make a change in the listing standard. As currently written the hubs can't even be used with IMC even though the threads are identical to those of RMC.
There is a process to submit proposals to change listing standards. I have not tried it, but it does not appear to be near as easy as submitting a PI to change the NEC.

Don I nominate you to try it
Seems like this would also take care of the age old EMT fittings into bell boxes issue as well.

 

[don_resqcapt19]

Don I nominate you to try it
Seems like this would also take care of the age old EMT fittings into bell boxes issue as well.

I don't have to worry about the real world anymore...just the play one on these forums

 

[wwhitney]

Seems like this would also take care of the age old EMT fittings into bell boxes issue as well.

Seems simple enough to me--EMT connectors are just for putting in holes in sheet metal enclosures. If you want to go into a threaded hub, you need something like this:

Bridgeport

BETTER WAYS TO GET THE JOB DONE RESOURCES Related products Bridgeport Compliance Documents ASK US ABOUT BRIDGEPORT

www.bptfittings.com

Or you can use a rigid nipple and an EMT to rigid transition coupling.

Cheers, Wayne

 

[electrofelon]

Seems simple enough to me--EMT connectors are just for putting in holes in sheet metal enclosures. If you want to go into a threaded hub, you need something like this:

Bridgeport

BETTER WAYS TO GET THE JOB DONE RESOURCES Related products Bridgeport Compliance Documents ASK US ABOUT BRIDGEPORT

www.bptfittings.com

Or you can use a rigid nipple and an EMT to rigid transition coupling.

Cheers, Wayne

True.......or......we could get rid of the listing nonsense so we don't have to worry about 1 out of 20 inspectors that call it or have to chase down an oddball fitting that no one stocks.