panel chases

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Jim W in Tampa

Senior Member
Location
Tampa Florida
renosteinke said:
I don't like the practice, for two reasons: there is the protection the cables need against abrading against the end of the pipe, and there is no effective strain relief for the cables (a tug gets transmitted direct to the wire connections).

That said ... I'm guilty of setting the stage for exactly this sort of thing. That is, I install such a chase for possible future additional wires. Did I say 'possible?' So far, the chases have nearly always been used, as things were added.

I suppose that such chases could be made kosher with the addition of a gutter on top, and the use of cable clamps.

If used with a box and cover at other end it is legal.It does have me rethinking if that is just as bad as a chimney
 

iwire

Moderator
Staff member
Location
Massachusetts
I find it funny so many are worried about a the NMs burning when PVC burns just as well.

I see no special issue about fire here.
 

Jim W in Tampa

Senior Member
Location
Tampa Florida
iwire said:
I find it funny so many are worried about a the NMs burning when PVC burns just as well.

I see no special issue about fire here.
Bob,what i see as problem is that large 2 inch chimney and not that 1/2 inch romex connector half full with wire.I do agree both will burn.
Main problem is its a mis use of male adapter and not fastening the wire.
 

Ebow

Member
The fire issue looks to be suppressed by the fire rated foam in the top of the two inch. This works well, I have seen it. Also if the foam in applied into the top of the pipe a couple of inches it will work on the strain issue also to a large degree. Ever try to pull a wire out of that stuff when you could not pull straight up or down? Besides that when the panel is all made up with the nice bends that keep the wires to the outer edges of the panel, then all nice and zip tied together pulling on one wire is not likely to cause strain on its connection.
There is another issue that is possible but you can not see it in the OP picture.

Gene
_________________________________
Remember - Speed Kills and it may not always be you.
 

Dennis Alwon

Moderator
Staff member
Location
Chapel Hill, NC
Occupation
Retired Electrical Contractor
Ebow said:
The fire issue looks to be suppressed by the fire rated foam in the top of the two inch.

This is true but if you use fire rated foam I believe you are subject to derating your NM cables. art. 334.80
 

Jim W in Tampa

Senior Member
Location
Tampa Florida
Ebow said:
The fire issue looks to be suppressed by the fire rated foam in the top of the two inch. This works well, I have seen it. Also if the foam in applied into the top of the pipe a couple of inches it will work on the strain issue also to a large degree. Ever try to pull a wire out of that stuff when you could not pull straight up or down? Besides that when the panel is all made up with the nice bends that keep the wires to the outer edges of the panel, then all nice and zip tied together pulling on one wire is not likely to cause strain on its connection.
There is another issue that is possible but you can not see it in the OP picture.

Gene
_________________________________
Remember - Speed Kills and it may not always be you.

That still does not permit the use of the MA and foam is not a listed fastener.
 

Ebow

Member
OK Jim, maybe I am lost here. But is not a length of pvc with a MA, lock ring, and bushing the same as a RMC nipple with a lock ring and bushing? I mean I see this install all the time and do not understand how it is the mis-use of a MA. Tell me something I do not know and I will be glad for the knowledge.

Gene
__________________________________
Remember - Speed Kills and it may not always be you.
 

Jim W in Tampa

Senior Member
Location
Tampa Florida
Ebow said:
OK Jim, maybe I am lost here. But is not a length of pvc with a MA, lock ring, and bushing the same as a RMC nipple with a lock ring and bushing? I mean I see this install all the time and do not understand how it is the mis-use of a MA. Tell me something I do not know and I will be glad for the knowledge.

Gene
__________________________________
Remember - Speed Kills and it may not always be you.

Its simple,the MA is not listed as a connector for romex.
 

Ebow

Member
Thanks Jim, I understand that. Just makes me wonder why something that falls under a violation is an accepted practice. I have only seen one fail and it was cited for modification of the enclosure by increasing the 1 1/2" factory KO to 2". The installation of two 2" by 2 1/2" reducing washers to cover the half moon openings of the 1/2" KO's was all he required.
I guess I am going to have to dig into it a little more in depth and see how it is allowed to pass.

Gene
_____________________________________
Remember - Speed Kills and it is not always you.
 

benaround

Senior Member
Location
Arizona
Ebow, I've been going round and round with this myself.

312.5(C) basiclly says, each cable shall be ' secured ' to the panel , right ?

334.30 last sentence says, sections of cable protected ----by raceway

shall not be required to be ' secured ' within the raceway.

I have posted this in 2-3 threads with out any comments for or against, if

this means it's ok to not use romex connectors when using PVC pipe as in

the OP ?? What do you think ?
 

jwelectric

Senior Member
Location
North Carolina
benaround said:
Ebow, I've been going round and round with this myself.

312.5(C) basiclly says, each cable shall be ' secured ' to the panel , right ?

334.30 last sentence says, sections of cable protected ----by raceway

shall not be required to be ' secured ' within the raceway.

I have posted this in 2-3 threads with out any comments for or against, if

this means it's ok to not use romex connectors when using PVC pipe as in

the OP ?? What do you think ?

Is not 334.30 addressing the Securing and Supporting of the cable along its length and not addressing the connections to the box?
 

benaround

Senior Member
Location
Arizona
Bulldog,

It sure seems that way Mike. I'm looking for an answer to this, I'm not stating

an opinion. Little backround: About 3-4 weeks ago in a similar thread to this

one, regarding NM cables in a raceway connected to a panel, I posted "that

I did not think it was ever a code compliant method ". Other members posted

back " I'm not following you Frank, what about 334.30 ? ". So I read it and

thought maybe this is one of those sections that goes by 'Charlies' Rule" and

had been discussed and I missed it.

So hear is my take on this, Basic rule you need rx connectors, if you have a

'surface mounted' panel and follow 312.5(C)excpt. (a)-(g) a raceway can be

used, without rx connectors of course. Lastly a flush mount panel can not

have a raceway as described above period. Do you agree with that ? Thanks
 

jwelectric

Senior Member
Location
North Carolina
benaround said:
benaround said:
So hear is my take on this, Basic rule you need rx connectors, if you have a
'surface mounted' panel and follow 312.5(C)excpt. (a)-(g) a raceway can be
used, without rx connectors of course. Lastly a flush mount panel can not
have a raceway as described above period. Do you agree with that ? Thanks

Yes I agree with you completely.

I also disagree with the practice of installing a metal box with a short piece of conduit to install a receptacle on a basement wall as this is a violation of 314.17(B) unless there is a box on both ends of the pipe.

NM cable is allowed to be installed in a raceway system in which case the raceway would be connected to the box on both ends and the cable would be contained within.

What I was hoping for with this thread was some debate as to the why these sections of code require a cable to be secured to a box or panel (312.5(C)ex and 314.17(B) )when a short piece of pipe is used to install the cable such as in the picture.
 

jwelectric

Senior Member
Location
North Carolina
Does anyone have access to the ROP or ROC from the 1993, 1996, 1999, 2002 code cycles as I think these will have some information concerning this type of installation, please.
 
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