Rigid galvanized coupling to liquid tight flex connections

Until the inside of an outdoor raceway becomes a "dry location" what difference is all this going to make?
The conductors we select must be suitable for wet locations for this reason so what difference does it make whether or not the threads are tapered or not?

Jap>
 
I dare someone to cut open a ul listed grc threaded coupling...
Npt is very visible!
If we could just start calling threads either npt or machine... it may get much more simple.
 
rambojoe said:
I dare someone to cut open a ul listed grc threaded coupling...
Npt is very visible!
If we could just start calling threads either npt or machine... it may get much more simple.
Click to expand...
As previously mentioned, Listed coupling have NPS straight threads they are not NPT tapered.
This means a proper length tapered conduit will eventually jam as it is threaded into a coupling providing a secure grounding connection, but not necessarily a watertight one.
 
jim dungar said:
As previously mentioned, Listed coupling have NPS straight threads they are not NPT tapered.
This means a proper length tapered conduit will eventually jam as it is threaded into a coupling providing a secure grounding connection, but not necessarily a watertight one.
Click to expand...
Well im clear on what it is... and how it works... sorry i started skipping to the end.
4 pages... wow
There are a few that should cut one in half...
You dont need a weatherman to know which way the wind blows.
 
electrofelon said:
So whoever wrote the standard is a clueless moron(s) because they didn't think about all the threaded things that these would get screwed into.
Click to expand...
If grasshopper chooses the wrong parts, is it the supplier’s fault for offering the selection?
 
jap said:
Until the inside of an outdoor raceway becomes a "dry location" what difference is all this going to make?
The conductors we select must be suitable for wet locations for this reason so what difference does it make whether or not the threads are tapered or not?

Jap>
Click to expand...
One thing is if the straight thread fitting in straight thread coupling happens to loosen up by just a degree or two of rotation, bonding is more compromised than it would be for tapered thread into straight coupling that had been made up wrench tight as there is still going to be some significant wedging of the taper into the straight fitting where the straight to straight is pretty loose with little backing out. This is a reason the RMC/IMC sections don't allow "running threads" where a union type fitting needs to be used. Running threads is straight threads until you get to where the die was still on the pipe when you stopped threading.
 
ramsy said:
If grasshopper chooses the wrong parts, is it the supplier’s fault for offering the selection?
Click to expand...
What parts are available or who chooses them is irrelevant to my point. The product standard should have been written by someone who actually has at least some practical electrical experience and would thus know they need to be screwed into hubs and other female threads.
 
kwired said:
One thing is if the straight thread fitting in straight thread coupling happens to loosen up by just a degree or two of rotation, bonding is more compromised than it would be for tapered thread into straight coupling that had been made up wrench tight as there is still going to be some significant wedging of the taper into the straight fitting where the straight to straight is pretty loose with little backing out. This is a reason the RMC/IMC sections don't allow "running threads" where a union type fitting needs to be used. Running threads is straight threads until you get to where the die was still on the pipe when you stopped threading.
Click to expand...

Good point.
I sometimes need to be reminded most don't pull an EGC like I generally always do.

Jap>
 
electrofelon said:
What parts are available or who chooses them is irrelevant to my point. The product standard should have been written by someone who actually has at least some practical electrical experience and would thus know they need to be screwed into hubs and other female threads.
Click to expand...
The product standards are consensus standards and anyone can submit a proposed change just like with the NEC. However, I don't know exactly how that process works with a UL standard.
 
electrofelon said:
The product standard should have been written by someone who actually has at least some practical electrical experience and would thus know they need to be screwed into hubs and other female threads.
Click to expand...
The product standards I have look at (mostly UL 514B) have two different product categories. A "connector" is for terminating a wiring method to an enclosure. It may consist of straight or tapered threads, in which case it is usually provided with a locknut (if the threads are non-standard, then it must be provided with a locknut). I don't think the product standards use this term, but a "male adapter" is a fitting to connect to a female threaded hub or fitting. It typically does not come with a locknut (not sure if it is prohibited to provide one) and is marked on the product container to the effect that it is OK to use with a hub or female threaded fitting.

For PVC, the distinction is very clear. A box connector has not threads and is designed to glue into a coupling. While a male adapter is designed to any female threaded fitting or hub.

Cheers, Wayne
 
Isaiah said:
The contractor ran 3/4” LFMC into a 3/4 GRC coupling -
Our client is saying this is an ‘illegal’ connection because the coupling is NOT listed for flex conduit. Where is this stated the NEC?


Sent from my iPhone using Tapatalk
Click to expand...
Since there does exist a listed changeover fitting wouldn't it be easiest to get the right fitting and change it?
 
jeffelectric1992 said:
Since there does exist a listed changeover fitting wouldn't it be easiest to get the right fitting and change it?
Click to expand...

Of course it would except the conduit and cable has already been ran to the equipment and terminated. Quite a lot of rework


Sent from my iPhone using Tapatalk
 
You must log in or register to reply here.
Top