Bushings for PVC

Status
Not open for further replies.
300.4(G) is your answer. Just out of curiosity the title of your post says PVC and you referenced the section for HDPE:?

Pete
 
352.46 Bushings. Where a conduit enters a box, fitting, or
other enclosure, a bushing or adapter shall be provided to
protect the wire from abrasion unless the box, fitting, or
enclosure design provides 352.46 Bushings. Where a conduit enters a box, fitting, or
other enclosure, a bushing or adapter shall be provided to
protect the wire from abrasion unless the box, fitting, or
enclosure design provides equivalent protection..
Click to expand...

In my opinion yes unless the inspector feels that a typical MA provides equivalent protection.

I think many MAs have very sharp edges compared to a bushing.
 
remillard said:
Sorry Pete, my mistake, if we are installing PVC with conductors smaller than #4 example 1/2"to 1".
Is it still required that we install a bushing on the male PVC connector?
Click to expand...

The answer is yes unless, as Bob pointed out, the inspector feels that the MA will not damage the conductor.

Pete
 
Wow ! That opened a whole box of worms for me.
I have always let 300.4(G) be my guide for all conduits. Odd that we have ***.46 for RGS and IMC and PVC but not for EMT.
Are we saying a 1/2" RGS, or PVC conduit with MA needs a bushing but a 1/2" EMT with a connector does not ?
 
augie47 said:
Wow ! That opened a whole box of worms for me.
I have always let 300.4(G) be my guide for all conduits. Odd that we have ***.46 for RGS and IMC and PVC but not for EMT.
Are we saying a 1/2" RGS, or PVC conduit with MA needs a bushing but a 1/2" EMT with a connector does not ?
Click to expand...

Apparently so. As an inspector I have never thought much about it unless it was 4awg or larger. Wonder if I should be:?
 
pete m. said:
Apparently so. As an inspector I have never thought much about it unless it was 4awg or larger. Wonder if I should be:?
Click to expand...

I have always done likewise. I always thought bushings were a good idea on RGS or IMC of any size but never enforced it except for #4 or larger.
Guess I should learn to read the book after 50 years :)

I can't, however, see any logic in requiring a bushing on a 3/4 PVC with a male adapter and not on a 3/4 EMT with a connector.
 
You bring a good point about the EMT connectors. A half-sharp pocket knife ran around the interior edge on a PVC MA will get rid of the sharp edge and then it would be just as good as any EMT connector I have came across.

Pete
 
pete m. said:
You bring a good point about the EMT connectors. A half-sharp pocket knife ran around the interior edge on a PVC MA will get rid of the sharp edge and then it would be just as good as any EMT connector I have came across.

Pete
Click to expand...

Sounds like you need to sharpen your pocket knife to full-sharp. ;)
 
My question is why do most PVC MA's have a fairly sharp edge in the first place.

Maybe so they can also sell bushings.

Most EMT fittings have smooth edges or even a non metallic bushing as a part of the fitting.

GRC and IMC makes sense to use bushings as the cut edge is often sharp.

Then there is the rule that assumes that conductors 4 AWG and larger are subject to more abrasion no matter what kind of fitting is used for terminations:?. I play along with the game but never understood why the rules are what they are in some cases.
 
Cavie said:
.....bushings or adaptors are required........ PVC MA=male adapter.
Click to expand...

A bushing or adapter shall be provided to protect the wire from abrasion.......

A male adapter that has a sharp edge does not protect the conductors from abrasion IMHO.

Chris
 
raider1 said:
A bushing or adapter shall be provided to protect the wire from abrasion.......

A male adapter that has a sharp edge does not protect the conductors from abrasion IMHO.

Chris
Click to expand...

Yep. I use a solid metal bushing to pull the conductors, the pull string/rope can cut into the male PVC adapter easily and damage it or the conductors on the pull, and then replace it with a cheapo plastic one for inspection.
 
iwire said:
Interesting.

I am not saying you are wrong but if we do read it that way when would a bushing for PVC conduit be required by this section?
Click to expand...

I'm thing they had a couple of options in mind. A pvc bushing on the inside and a pvc coupling on the out side or a pvc ma and locknut. Also a pvc bushing on the inside and a pvc LB on the outside?
 
I think they are most likely referring to a PVC box adapter. Either way, nobody uses bushings on MA's around here unless the wire is #4 or larger.
 
remillard said:
According to Article 353.46, is it neccessary to use bushings when using male pvc adapters when terminating PVC to a box or enclosure?
Click to expand...

iwire said:
In my opinion yes unless the inspector feels that a typical MA provides equivalent protection.

I think many MAs have very sharp edges compared to a bushing.
Click to expand...

raider1 said:
I agree and require bushings for PVC MA's.

Chris
Click to expand...

remillard said:
Sorry Pete, my mistake, if we are installing PVC with conductors smaller than #4 example 1/2"to 1".
Is it still required that we install a bushing on the male PVC connector?
Click to expand...

Seems we had some differing opinions about this in an earlier thread.
Look here.
 
jumper said:
Yep. I use a solid metal bushing to pull the conductors, the pull string/rope can cut into the male PVC adapter easily and damage it or the conductors on the pull, and then replace it with a cheapo plastic one for inspection.
Click to expand...

Same here. The trick is to remember to put on the plastic bushing BEFORE you terminate! :dunce:
 
Status
Not open for further replies.
Top