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RandomS
09-02-2008, 03:53 PM
I am replacing an existing fiberglass double-gang electrical box with a PVC triple-gang old-work box (a Carlon B355R box: http://carlon.com/Brochures/7F61.pdf). The new triple-gang box has internal plastic cable clamps of the type that apply constant pressure to the NM cable sheathing to hold the cable in place. You can see these clamps pretty clearly in Carlon's brochure.

With new cable, these clamps seem to work pretty well. It's easy to pull the cable through the clamp, and it holds the sheathing tightly and safely (to my eye). However, I have to bring the existing NM cables (which are 14/2 of circa 1986 vintage, in good shape) into this box, and of course they already have the sheathing stripped back. The sheathing just barely reached into the old box, and the new box is deeper. The different geometry means that the sheathing on the old wires doesn't reach the new box's cable clamps (by about an inch). Instead, the clamps would clamp on each individual wire's insulation, even biting into the insulation a bit (the plastic clamps have sharp edges). And of course the individual wires don't want to come through the clamp properly centered, they want to sneak around the sides and generally misbehave. This seems like bad news to me.

Any advice on dealing with this?

Chris75
09-02-2008, 04:16 PM
If the sheathing is not long enough, then I would just add some sheathing from a new piece of wire.

Bob NH
09-02-2008, 05:13 PM
If the sheathing is too ragged to get new sheathing in place you might add some tape held in place by shrink-tubing.

I would like to see the new sheathing overlap the old. If you can slip sheathing over the wire then it probably is a bit loose and those plastic tabs don't really clamp effectively. Even with new sheathing over the cable I would add shrink tubing to keep it in place.

Alectrician
09-02-2008, 05:35 PM
90% of the time in rework I tear out the clamps with needlenose.

The cable is stapled to the stud. Unless a leprechaun gets in there and pulls the cable out, it's not going anywhere.

As long as the sheath is in the box, you're good.

RandomS
09-03-2008, 08:21 AM
Alectrician, I think you have an excellent point. And that suggestion certainly is easy to implement! I can use the clamps where new cable comes into the box, and remove the clamps on the old wiring openings.

One follow-up question: Once the clamp is removed, it leaves a pretty big opening. Would it be better to bring two of the old cables in through the same (nearest) opening, thus maximizing the amount of sheathing in the box, or is it better to use separate openings for each cable? (I wouldn't clamp two cables in the same clamp, but now we're talking about unclamped openings.)

jwelectric
09-03-2008, 08:34 AM
Just what is the purpose of having the box in the first place?

Could it have anything to do with confinement of any type of arc that could occur?

What is being told to an untrained person is to just forget about the confinement requirement that the box is installed for in the first place or to just jury rig something that might fool someone looking in but does nothing for containment of an arc or the protection of the conductors contained therein.

Then we wonder just how some of the installations were achieved the way they were.

Please people if you are not going to tell someone how to do something correctly then just donít tell them anything.

RandomS
09-03-2008, 08:49 AM
jwelectric, that's a great point about confinement. In light of that, how best to bring the old wiring (with the sheathing already stripped) into the box, while maintaining the integrity of the box? Replace the missing sheathing with shrink tubing, as suggested earlier?

This is why these forums are so helpful!

jwelectric
09-03-2008, 10:15 AM
jwelectric, that's a great point about confinement. In light of that, how best to bring the old wiring (with the sheathing already stripped) into the box, while maintaining the integrity of the box? Replace the missing sheathing with shrink tubing, as suggested earlier?

This is why these forums are so helpful!

You have only two code compliant options.

1- replace the nonmetallic cable
2- move the box to where the existing cable enters the box

The idea of trying to replace the sheathing is bogus as anything I have ever heard in my entire life. The sheathing is required to be continuous from start to finish and repair is not allowed in any circumstance.

Anything short of these two methods is nothing short of dumb, stupid, crazy or any other adjective one would like to describe the installation. One that comes to mind to describe those things that have been stated so far sounds like some type of male to female bonding that is aimed toward the sky or some other upward direction.

RandomS
09-03-2008, 11:09 AM
I hear you.

With that in mind, how do you replace a box with one of these old-work boxes? I'm assuming that most of the time, replacing all of the cables entering the box is not a practical option, and neither is moving the box (which wouldn't help anyway -- cables enter from both top and bottom).

jwelectric
09-03-2008, 11:40 AM
I hear you.

With that in mind, how do you replace a box with one of these old-work boxes? I'm assuming that most of the time, replacing all of the cables entering the box is not a practical option, and neither is moving the box (which wouldn't help anyway -- cables enter from both top and bottom).

Again experience comes into play here. A different type of box could solve your problem or even the installation of another box either above or below could solve your problem.

What you CANĒT do is add sheathing to the cable or any other type of junk such as heat shrink or tape to make it look a little better.

When I bid this type of work I will include the proper method of installation in the bid then it is up to the person paying the bill to decide if they want me doing their work or not.

What I will not do is some of the junk that has been posted here and neither should you.

If there is conductors entering the bottom of the box then simply add a receptacle under the switch and use that box for some of the joints with a new cable from the receptacle up.

Chris75
09-03-2008, 01:05 PM
The idea of trying to replace the sheathing is bogus as anything I have ever heard in my entire life. The sheathing is required to be continuous from start to finish and repair is not allowed in any circumstance.



No its not, I called southwire on this, they say its not required and tape is perfectly fine, so at least I did my part of the homework. :rolleyes:

jwelectric
09-03-2008, 01:19 PM
No its not, I called southwire on this, they say its not required and tape is perfectly fine, so at least I did my part of the homework. :rolleyes:

Hey I called the fellow down at the local service station and he said...............

I think that you would be better to call someone responsible for testing the cable than someone that manufactures the stuff. All that Southwire is interested in is sales.

Do some more homework and see what UL or NEMA has to say about damaged cable.

RandomS
09-03-2008, 02:22 PM
I can bring the old cable into the new box with the sheathing intact. I just can't do it through the new box's internal cable clamp -- it won't reach. What I can do is make a hole just big enough for the sheathing to pass through, right next to the clamp. There won't be any more of an opening in the box than there would be if I used the cable clamp (which after all, is far from airtight).

The obvious downside is that the old cable won't be secured to the box. Given that it's stapled to the stud a few inches outside the box, how big a deal is this actually? What is the scenario where this would cause a problem?

maintenanceguy
09-03-2008, 03:29 PM
NEC requires 1" of sheathing to be inside the box. Frankly, any sheathing showing within the box would satisfy me.

How about ignoring the integral cable clamps, making a 1/2" knockout and using a standard romex connector. That gets you an extra 1/2".

Or, the right way would be to install a box above and below this box and use them as splice boxes to get new wire to your replacement box. A box near the ceiling and one near the baseboard painted or wallpapered to match (but not covered over and concealed) wouldn't even be noticed.

Chris75
09-03-2008, 04:27 PM
Do some more homework and see what UL or NEMA has to say about damaged cable.

Since you mentioned it, show me the text where its a problem.

Chris75
09-03-2008, 04:34 PM
NEC requires 1" of sheathing to be inside the box. Frankly, any sheathing showing within the box would satisfy me.



Its not 1", its 1/4"

jwelectric
09-03-2008, 07:25 PM
Since you mentioned it, show me the text where its a problem.

See UL Standard 719 for complete details to the action needed for the sheathing of NM cable

NEMA 3.13.1 calls for replacement in their NEMA Standards Publication RV-2 which can be found on the NEMA site

RandomS
09-04-2008, 02:24 PM
Thanks to everyone who has contributed to answering my question. Here's what I think I'll do:

I believe the old cables are well supported by being stapled to the stud close to the box. Therefore, I'll put holes in the new box just large enough for the old cables' sheathing to pass, in a position where just as much sheathing will be inside the new box as was inside the old box (at least 1/4"). The clamp in that position will remain closed.

The new cables will simply be installed via the internal clamps, as usual.

maintenanceguy
09-04-2008, 03:12 PM
Its not 1", its 1/4"

I immediately went to the book to prove you wrong.

After a little searching I found 314.17.

Turns out I was wrong. I stand corrected.

Alectrician
09-04-2008, 04:55 PM
Anything short of these two methods is nothing short of dumb, stupid, crazy or any other adjective one would like to describe the installation.

If you think that clamp closes the gap, you are smoking crack. That clamp is about an inch long and the cable is about 3/8 thick. Draw a picture and do the math. The gap in the opening is exactly as big with or without the clamp. Have you ever actually worked in the field?

And, there is NOTHING wrong with slipping sheathing over wires.

Guys like JW are just wound way too tightly and do not allow themselves to think freely.

Here is a compromise. Don't cut the clamp all the way out. Cut it short enough to function but still allow the sheath to be seen. This remanufacturing/altering of listed products of course is highly illegal and dangerous and will likely resuly in a firey death of your entire family.




OP. I run as many wires as I can thru one opening. It makes the make up cleaner/neater.

Chris75
09-04-2008, 07:01 PM
If you think that clamp closes the gap, you are smoking crack. That clamp is about an inch long and the cable is about 3/8 thick. Draw a picture and do the math. The gap in the opening is exactly as big with or without the clamp. Have you ever actually worked in the field?

And, there is NOTHING wrong with slipping sheathing over wires.

Guys like JW are just wound way too tightly and do not allow themselves to think freely.




I agree, I used to dislike 220, but then I realized I was just brainwashed by mike holts code forum. ;):D

jwelectric
09-05-2008, 08:35 AM
So based on the last two replies I suppose that the letter of the codes can be thrown out the window when it is being done by someone other than a licensed person.

Right is Right and wrong is wrong no matter who is making the installation so if you decide to do as these idiots are telling you then more power to the lot to you.

If you decide that you want to make a professional installation then do it the right way.

The choice is yours and the battle will be between you and your insurance company should they ever need to do a pay off due to a jury rigged installation.

Bob NH
09-05-2008, 12:15 PM
The choice is yours and the battle will be between you and your insurance company should they ever need to do a pay off due to a jury rigged installation.

I suspect that, at least with respect to homeowners, "The insurance won't pay" argument does not apply. I would like to see a citation from a real policy.

I have carefully examined my homeowners insurance policy, which is the contract between me and the company, and there is nothing in it about not paying for loss or injury resulting from work not done to code or without a permit, whether done by myself or others.

There may be something in a business policy but nothing in a homeowners policy that I have ever seen.

I am also familiar with provisions of professional policies such as "Errors and Omissions" policies that cover engineers and architects. They explicitly cover the consequences of errors and omissions, with some provisions that depend on the policy.

I'm calling your bet. Show 'em or I collect the pot.

jwelectric
09-05-2008, 01:54 PM
I'm calling your bet. Show 'em or I collect the pot.


It will not be a matter of the insurance paying off or not as in most states the insurance will pay off.

It is a matter that the insurance company can and has counter sued for the loss due to an illegal installation or one that has not been documented by an inspection.

Come back

Alectrician
09-05-2008, 02:38 PM
Right is Right and wrong is wrong

That is exactly what your problem is.

Nothing in life is black and white. Everything is open to interpetation and judgement.

Just because it's the law doesn't make it right. I have proven that to you but of course did not get a response. Radicals can never win a debate because they are stuck on one thing. They do not allow anything in that doesn't fit their criteria.



I agree, I used to dislike 220, but then I realized I was just brainwashed by mike holts code forum.

Aw come on Chris. NOBODY dislikes me. I'm the nicest guy in the world ;)

You may dislike my opinions or disagree with how I present them but there is no way anyone could not love me ;)

Bob NH
09-05-2008, 02:55 PM
It will not be a matter of the insurance paying off or not as in most states the insurance will pay off.

It is a matter that the insurance company can and has counter sued for the loss due to an illegal installation or one that has not been documented by an inspection.

Come back

The homeowner's insurance company may sue the pro who installed something contrary to code, but they would have to show that it caused the loss.

In that case the installers insurance company should defend him and pay any judgement.

jwelectric
09-05-2008, 05:17 PM
The homeowner's insurance company may sue the pro who installed something contrary to code, but they would have to show that it caused the loss.

In that case the installers insurance company should defend him and pay any judgement.

The insurance has also been known to sue the homeowner when noncompliant, non-permitted and non-inspected installations have been made.

Chris75
09-05-2008, 05:26 PM
Mike, all I can say is I have proven you wrong more than once on this site, so you can feel any way you want towards me, I am a PROFESSIONAL electrician, but I also live in the real world, not la-la land. :rolleyes:

Bob NH
09-05-2008, 06:35 PM
The insurance has also been known to sue the homeowner when noncompliant, non-permitted and non-inspected installations have been made.

Please provide the case citation and verdict. I am very interested in any case where a homeowner's insurance company as sued the homeowner insured by the company. The legal basis should be interesting.

codeone
09-05-2008, 07:26 PM
ive noticed alot of different thoughts on this issue some of them very adamate. But you do have to admit that by cutting the clamps off you are altering the ul listing of the box and by drilling other holes in the box you are doing the same. Also you are not making a code compliant instullation. Most likely a code official would turn you down if you had the required permit and inspections. How you resolve the issue is always best if you try to be compliant for everybodys sake.
Weather you try to do things right by code or not is a matter of conscience. But a good Electrician will always try to do a code compliant job.Because the code is for a reasonably safe system not a cheap way to do things.

jwelectric
09-05-2008, 07:41 PM
Mike, all I can say is I have proven you wrong more than once on this site, so you can feel any way you want towards me, I am a PROFESSIONAL electrician, but I also live in the real world, not la-la land. :rolleyes:


I have never said that I am perfect and yes I do buy pencils with erasers on them but when it comes to telling someone to slide a piece of PVC sheathing where there was fabric sheathing is far from professional.

To even suggest replacing a piece of sheathing over the conductors is nothing short of criminal and there is nothing professional about it except those who want to be remembered as a professional %$&#*@

Bob NH
09-05-2008, 09:58 PM
3M and many others have heatshrink tubing and wrap-around repair kits for ranges of voltages exceeding 1000 Volts. Many meet UL 224 requirements for cable jacketing. They can certainly be used safely to replace or repair jacketing on NM cable without risk of burning the house down.

http://www.intertech-eng.com.au/public/editor_images/Solution_Guide.pdf

http://www.electriciantalk.com/showthread.php?t=31

http://www.ablewire-cable.com/tables/165.html

http://www.dsgcanusa.com/products/product_lowvoltage.htm

http://www.portplastics.com/pec/heatshrink/sumisleeve.html

http://ulstandardsinfonet.ul.com/tocs/tocs.asp?doc=s&fn=0224.toc

http://www.alcomet.net/pdf/heatshrink.pdf

Alectrician
09-06-2008, 01:06 AM
To even suggest replacing a piece of sheathing over the conductors is nothing short of criminal

What can POSSIBLY happen?

Use your imagination and stretch it to the limit. I could be wrong but I am drawing a blank on this one.

Chris75
09-06-2008, 06:31 AM
What can POSSIBLY happen?

Use your imagination and stretch it to the limit. I could be wrong but I am drawing a blank on this one.


I'm not going to argue this one anymore, Mike is entitled to his opinion. I think I will start this thread on Mike Holts forum just for giggles.

jwelectric
09-06-2008, 06:39 AM
3M and many others have heatshrink tubing and wrap-around repair kits for ranges of voltages exceeding 1000 Volts. Many meet UL 224 requirements for cable jacketing. They can certainly be used safely to replace or repair jacketing on NM cable without risk of burning the house down.


What can POSSIBLY happen?

Use your imagination and stretch it to the limit. I could be wrong but I am drawing a blank on this one.

Budweiser makes one hell of a beer can and with a couple of hose clamps it makes a real good coupling for EMT also.

We all know that duck tape will hold a hood on at 200MPH so why not use a little duck tape to hold electrical things in place.

Just where did Joe go? No wonder he deleted the whole forum if this is the type of advice that was being given out by the members.

Just what do you teach your children? Is not right, right and wrong, wrong?

jwelectric
09-06-2008, 06:51 AM
I'm not going to argue this one anymore, Mike is entitled to his opinion. I think I will start this thread on Mike Holts forum just for giggles.


I just looked and didn't find your post. Are you going to post a link here to it?

Well are ye or ain’t ye

Three hours later and still not done. Are you scared to make the post?

Alectrician
09-06-2008, 11:12 AM
Heh heh.....Can't answer the question huh? The question wasn't about beer cans or duct tape. Try again. Use your imagination but stick to cable sheath.





Just what do you teach your children? Is not right, right and wrong, wrong?

I teach my children to think for themselves. All I can offer is guidance.

Right is relative, NOT absolute. Dude, I barely made it thru high school and I know that much. If you have any ability to read and comprehend you would have at least acknowledged the points I've made showing this to be true.

Here is another question to skirt. Jesus is right according to Christians, Allah is right according to Muslims. Which is actually right?

jwelectric
09-06-2008, 11:44 AM
Heh heh.....Can't answer the question huh? The question wasn't about beer cans or duct tape. Try again. Use your imagination but stick to cable sheath.






I teach my children to think for themselves. All I can offer is guidance.

Right is relative, NOT absolute. Dude, I barely made it thru high school and I know that much. If you have any ability to read and comprehend you would have at least acknowledged the points I've made showing this to be true.

Here is another question to skirt. Jesus is right according to Christians, Allah is right according to Muslims. Which is actually right?

There is nothing that you have said that comes clsoe to being code compliant therefore nothing to address.

I sure hope that as you teach your children to think for theirself you also teach them right from wrong.

I hope that you can answer the second question for yourself. If you can't then may the Great Spirit have mercey on your soul.

jwelectric
09-06-2008, 11:45 AM
I think I will start this thread on Mike Holts forum just for giggles.

four hours and still waiting

Chris75
09-06-2008, 11:47 AM
four hours and still waiting

Get you panties out of a bunch, I had to go on a trouble call, seems like someone added some sheath and caught the wall on fire, guess you were right after all. :rolleyes:

jwelectric
09-06-2008, 12:03 PM
Get you panties out of a bunch, I had to go on a trouble call, seems like someone added some sheath and caught the wall on fire, guess you were right after all. :rolleyes:


Hope that no one was hurt by this hack type of installation :):p

Chris75
09-06-2008, 12:31 PM
Hope that no one was hurt by this hack type of installation :):p

Mike, you know I respect you, I just dont see the same view on this matter, but thats fine also.

jwelectric
09-06-2008, 12:44 PM
After some discussion with the electrical inspector and homeowner we have decided that a little black tape and some heat shrink could fix this problem. (http://i3.photobucket.com/albums/y63/jwelectric/needsheathing.jpg)

On the interior of the building we will slip a little sheathing over the conductors and all is well.

What do you all think?

jwelectric
09-06-2008, 12:44 PM
Mike, you know I respect you, I just dont see the same view on this matter, but thats fine also. I know but it is not as much fun as debating the points of the intent of the NEC

Alectrician
09-06-2008, 04:11 PM
You're a funny guy Mike. You dodge questions better than McCain and Obama combined.



I hope that you can answer the second question for yourself.

Of course I can but I was asking you. It was a rhetorical question anyway. I know exactly how you think.



After some discussion with the electrical inspector and homeowner we have decided that a little black tape and some heat shrink could fix this problem.

Yeah....that is exactly what we were talking about. An inch of sheath to extend into a plasic JB. You're funny dude.


BTW..... unprotected SE cable is one of those code compliant but dangerous things. We don't even do that in the wild west. We have more common sense than to run power lines within reach of children and landscapers :cool:

The book says it's right but common sense says it's wrong.

BigLou
09-06-2008, 04:20 PM
Just what is the purpose of having the box in the first place?

Could it have anything to do with confinement of any type of arc that could occur?



Mike,
I am not an electrician not even close. Last time I checked an arc can get to over 5k degrees am I supposed to believe that a plastic box is going to confine a 5000 degree arc in any meaningful way ?

Lou

BigLou
09-06-2008, 04:28 PM
I suspect that, at least with respect to homeowners, "The insurance won't pay" argument does not apply.

This is generally correct, they will however gladly sue any body they don't insure if they think they are at all to blame.

http://library.findlaw.com/1999/Jun/1/127907.html

jwelectric
09-06-2008, 05:48 PM
Mike,
I am not an electrician not even close. Last time I checked an arc can get to over 5k degrees am I supposed to believe that a plastic box is going to confine a 5000 degree arc in any meaningful way ?

Lou


Hey Lou
I'm no engineer but that is exactly the reason for having enclosures aroung joints, splices ect.........

Edited to add;
An arc flash can reach as high as 32000 degrees

jwelectric
09-06-2008, 08:34 PM
This is generally correct, they will however gladly sue any body they don't insure if they think they are at all to blame.

http://library.findlaw.com/1999/Jun/1/127907.html

as well as the ones they do insure if they are the blame

drick
09-07-2008, 08:21 PM
as well as the ones they do insure if they are the blame

Only if it was intentional. Insurance covers stupidity when it comes to a homeowner. Same holds true for the licensed guys. Their insurance pays when they screw up.

jwelectric
09-08-2008, 07:59 AM
Only if it was intentional. Insurance covers stupidity when it comes to a homeowner. Same holds true for the licensed guys. Their insurance pays when they screw up.

Believe it or not, installations such as described in this thread would be intentional and also noncode compliant and opens that door.