# More than one cable in NM connector?



## rgsgww (Jul 5, 2008)

Its ok only if the clamp is rated for more than two cables, this is done all of the time. Don't worry, its perfectly fine.


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## Ultrarunner2017 (Oct 1, 2008)

rgsgww said:


> Its ok only if the clamp is rated for more than two cables, this is done all of the time. Don't worry, its perfectly fine.


Thanks for your quick reply;
It looks as though the connectors are big enough to accomodate the two cables. Nothing appears squeezed or pinched.
I don't think it would be OK in the old metallic "Romex" connectors. I have stopped using those, even though I am always very careful not to over-tighten the screws. The NM ones are cheaper too<g>


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## hpp58 (Feb 28, 2008)

If they're rated you can use them.
I use two screw metal romex connectors all the time.


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## InPhase277 (Feb 9, 2008)

KE2KB said:


> Thanks for your quick reply;
> It looks as though the connectors are big enough to accomodate the two cables. Nothing appears squeezed or pinched.
> I don't think it would be OK in the old metallic "Romex" connectors. I have stopped using those, even though I am always very careful not to over-tighten the screws. The NM ones are cheaper too<g>


I have never checked the rating for any style of NM connector, but I have put in thousands upon thousands of both metal clamps and plastic hit-locks with two cables and never had a problem, either electrically or from an inspector.


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## Ultrarunner2017 (Oct 1, 2008)

Thanks for your help guys;
I have not worked with multiple cable metallic connectors, just the ones for single cables. I guess it's pretty simple. The rating / capacity should be stated on the package.
I just bought two packages of five NM type, but not sure if they are rated for more than one cable. I was planning to use them for single cables though.


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## Stubbie (Jan 7, 2007)

Almost all metallic clamps are rated for more than one cable..as an example 

Application: Indoors Only. Fits NM Cable: #14/2, #12/2, #12/3, AWG or 2 #14/2 AWG or Flex Cord .300 to .560 inches diameter 3/8" (1/2ko). Type: Twin Screw. In a dry location, use to connect nonmetallic sheathed cable to a steel outlet box or other metal enclosure. Miscellaneous: 3/8" size fits 1/2" knockout.


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## Ultrarunner2017 (Oct 1, 2008)

Stubbie said:


> Almost all metallic clamps are rated for more than one cable..as an example
> 
> Application: Indoors Only. Fits NM Cable: #14/2, #12/2, #12/3, AWG or 2 #14/2 AWG or Flex Cord .300 to .560 inches diameter 3/8" (1/2ko). Type: Twin Screw. In a dry location, use to connect nonmetallic sheathed cable to a steel outlet box or other metal enclosure. Miscellaneous: 3/8" size fits 1/2" knockout.


The ones I have been using have the top half of the clamp bend downward, instead of upward as the one shown. Are the clamps reversible?

For the non-metallic ones, is there a specification that says they are good for more than one cable? The ones I bought at HD yesterday don't list any cable occupancy specs.


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## theatretch85 (May 17, 2008)

KE2KB said:


> The ones I have been using have the top half of the clamp bend downward, instead of upward as the one shown. Are the clamps reversible?
> 
> For the non-metallic ones, is there a specification that says they are good for more than one cable? The ones I bought at HD yesterday don't list any cable occupancy specs.


There should be something on the outside of the package that indicates what you can put in the connector safely. 

Take a look at the link below, it shows the 3/4" version of the Arlington romex connector which indicates "1 or 2" cables:
http://www.foxelectricsupply.com/co...tDetail.asp?qsCatID=25007&qsProductNo=ARLNM95

Hope this helps!


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## Ultrarunner2017 (Oct 1, 2008)

theatretch85 said:


> There should be something on the outside of the package that indicates what you can put in the connector safely.
> 
> Take a look at the link below, it shows the 3/4" version of the Arlington romex connector which indicates "1 or 2" cables:
> http://www.foxelectricsupply.com/co...tDetail.asp?qsCatID=25007&qsProductNo=ARLNM95
> ...


Thanks for the link. I'll try those next. Today, I rewired some very old BX in my basement, and used this one for the NM cable.









I like them, but the Arlington looks simpler, since you don't need to use any tools to close them.


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## Leah Frances (Jan 13, 2008)

I would just like to curse the heart of the electrician who wired my breaker panel. Every single knockout had at least two NM running through them. That combined with the bird's nest inside the box made tracing the circuits a  - because, of course, none of them were properly labeled. 

Is there any reason not to knock out more knock-outs (other than the minor cost of the NM connectors)?


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## handyman78 (Dec 29, 2007)

Leah Frances said:


> Is there any reason not to knock out more knock-outs (other than the minor cost of the NM connectors)?


Probably just saving time in having to do this as well as the labor/effort to run single cables per knockout. My original 150a Murray panel which I just replaced was put in in 1971. The electrician used the larger knockouts like 1" or so and placed about 3 or 4 cables in each. My guess is that it was entirely legal at the time as it was inspected & approved by a reputable certified agency in my county.


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## Leah Frances (Jan 13, 2008)

And this was after I removed about 10 feet of decommissioned circuits that were just left tangled up in the box. All of the NM connectors on the right side are doubled up.


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## kbsparky (Sep 11, 2008)

Leah Frances said:


> ....Is there any reason not to knock out more knock-outs (other than the minor cost of the NM connectors)?


Not enough knockouts, in many cases... :whistling2:


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## Ultrarunner2017 (Oct 1, 2008)

The electrician who installed my new panel (200A CH), he not only doubled up on connectors / knockouts, but also used several shared neutrals in runs from the panel to J-boxes just above it to connect with wiring that would not reach the new panel.
He used 14/3 or 12/3 cable then split the circuits in the J-box.
I believe, but I am not sure he has these circuits on opposite legs. I need to check this out next time I go in there.


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## rgsgww (Jul 5, 2008)

KE2KB said:


> The electrician who installed my new panel (200A CH), he not only doubled up on connectors / knockouts, but also used several shared neutrals in runs from the panel to J-boxes just above it to connect with wiring that would not reach the new panel.
> He used 14/3 or 12/3 cable then split the circuits in the J-box.
> I believe, but I am not sure he has these circuits on opposite legs. I need to check this out next time I go in there.



Hopefully he did keep track of the wires. Theres nothing wrong with mini mwbc extending to j-boxes above the panel to feed short lines.


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