Question about running nm cable

[Jdsmith830]

We are having a house built. The main service panel is on the outside of the house. From that panel we are feeding two sub-pannels inside of the house. The contractor is installing an 1 1/4" PVC connector in the center top of each sub-pannel then pulling 20 to 25, 14/2, 12/2 nm cables through the 1 1/4" connector inorder to get the cables to the breakers. Is there any code problems with this.

 

[dnem]

We are having a house built. The main service panel is on the outside of the house. From that panel we are feeding two sub-pannels inside of the house. The contractor is installing an 1 1/4" PVC connector in the center top of each sub-pannel then pulling 20 to 25, 14/2, 12/2 nm cables through the 1 1/4" connector inorder to get the cables to the breakers. Is there any code problems with this.

Check all the conditions listed in 312.5(C)x

David

 

[kkwong]

Look in 312.5 (C) (I think)

Dnem beat me....

 

[raider1]

This would not be legal. Take a look at 312.5(C) as David pointed out.

Check all the conditions listed in 312.5(C)x

I don't think the Exception would apply to the OP's situation due to the fact that it appears that only a PVC conector is being installed, so you wouldn't have at least an 18" section of nonflexible raceway.

Chris

 

[lpelectric]

We are having a house built. The main service panel is on the outside of the house. From that panel we are feeding two sub-pannels inside of the house. The contractor is installing an 1 1/4" PVC connector in the center top of each sub-pannel then pulling 20 to 25, 14/2, 12/2 nm cables through the 1 1/4" connector inorder to get the cables to the breakers. Is there any code problems with this.

I would think there would be a problem in regard to conduit fill. :smile: See 300.17, 352.22 and also look at Table 1 of Chapter 9 where it says over 2 conductors must not fill to more than 40% of conduit. Then see note #4 to this Table that allows an increase to 60% for nipples not longer than 24". :smile:

 

[lpelectric]

Also see 312.5 (C)(g) since it's a conduit system:smile:

 

[Jdsmith830]

thanks for the advice

thanks for the advice

It did not seem right to me but I could not find the art. to support my concern. Thanks.

 

[infinity]

Are the subs surface mounted?

 

[220/221]

We are having a house built. The main service panel is on the outside of the house. From that panel we are feeding two sub-pannels inside of the house. The contractor is installing an 1 1/4" PVC connector in the center top of each sub-pannel then pulling 20 to 25, 14/2, 12/2 nm cables through the 1 1/4" connector inorder to get the cables to the breakers. Is there any code problems with this.

I don't know about the code issues but he aint gonna fit 25 12/2's in a 1 1/4" PVC. That is one FAT bundle o wires.

 

[Jdsmith830]

the 1 1/4" conectors are not surface mounted

the 1 1/4" conectors are not surface mounted

These panels are recessed in the wall. I found the article in the code which pertains to this installation it is 312.5 (c) exception. When t I told the contractor he would have to change the conduit to not less than 18" and only 40% fill, he complained saying that every contractor in the area installs the NM cable using only a connector. I told him to bad he stills needs to make it right according to NEC.

 

[raider1]

These panels are recessed in the wall.

Then the exception to 312.5(B) can't be used. The exception is for surface-mounted enclosures, not recessed enclosures.

Chris

 

[dnem]

Then the exception to 312.5(B) can't be used. The exception is for surface-mounted enclosures, not recessed enclosures.

Chris

You're right about the surface mounted spec being code but if we look at real life application, there are many inspectors thruout the country that waive the surface mounted requirement if all of the other conditions in 312.5(C)x are met. . I know that paragraph 2 of 90.4 is obviously intended to be used in situations covered by specific code wording, such as 230.2(C)(3), but in the real world it is common practice in many places to waive the surface mounted specification of 312.5(C)x.

Another example is white phasing tape at "termination" [200.6(B)(3)] or green phasing tape where "accessible" [250.119(A)(1)] for a black insulated 6 gauge wire has has gone on for decades and has continued to this day even tho the 1999 code set the cutoff point at larger than 6AWG.

David

 

[raider1]

You're right about the surface mounted spec being code but if we look at real life application, there are many inspectors thruout the country that waive the surface mounted requirement if all of the other conditions in 312.5(C)x are met. . I know that paragraph 2 of 90.4 is obviously intended to be used in situations covered by specific code wording, such as 230.2(C)(3), but in the real world it is common practice in many places to waive the surface mounted specification of 312.5(C)x.

Another example is white phasing tape at "termination" [200.6(B)(3)] or green phasing tape where "accessible" [250.119(A)(1)] for a black insulated 6 gauge wire has has gone on for decades and has continued to this day even tho the 1999 code set the cutoff point at larger than 6AWG.

David

I personally don't see why it should be allowed to install an 18" length of PVC conduit out of the top of a recessed panel and have the NM cable fed into the conduit. There is no reason that you can't install NM connector into the top of the recessed enclosure and attached the cables properly. The exception for the use of a conduit on a surface mount panel makes sense due to a couple of factors including, protection from physical damage and the requirement in 334.10(3).

As for the requirement for #6 wire to be identified by a continious white or grey color, my 1978 NEC requires #6 or smaller to be identified by a continious white or grey color.

I enforce the code as written and don't try to pick and choose what to enforce and what not to enforce, or change the rules to make them fit what I want to do.

Chris

 

[M. D.]

"Shot down in a blaze of glory."

9-11 Log #3091 NEC-P09 Final Action: Reject
(312.5)

____________________________________________________________

Submitter: Joseph A. Hertel, Safety and Buildings

Recommendation: Revise as follows:
Cabinets, cutout boxes, and meter socket enclosures [NEC 312.5]. (1) Cables
[NEC 312.5(C)] Substitute the following wording for 312.5(C) Exception
(intro):
Exception: Cables with entirely nonmetallic sheaths shall be permitted to
enter an enclosure through one or more nonflexible raceways of not less than a
fitting and not more than 10 ft in length, provided all of the following
conditions are met:
Delete 312.5(C) Exception paragraph (b).
Substitute the following wording for 312.5(C) Exception paragraph (c):
A fitting is provided on each end of the raceway to protect the cable(s) from
abrasion.

Substantiation: The required 18 in. length prevents use of this wiring method
in many instances. Reducing the length to that of a fitting would not create a
hazard. This method is becoming quite common where panels are placed in an
exterior location.
(b) A fitting or raceway used in this manner would have the same
characteristics if it was attached to the sides or bottom of the enclosure.
(c) The current language requires that the fittings remain accessible after
installation. This method is used in multifamily dwellings to bring the branch
circuits into a cabinet and the end of the raceway is not accessible after the
gypsum wall covering is installed. There is no real need for the accessibility
since modifications to the branch circuitry of multifamily dwellings are rarely
encountered.

Panel Meeting Action: Reject
Panel Statement: With respect to the three modifications proposed by the
submitter, the panel provides the following response:
1) The 18 inch minimum raceway length was chosen as a distance long
enough to provide reasonable containment of the enclosed cables without
specifying a length so long as to require mandatory derating of the cables.
Removal of this length requirement would create the possibility that the
enclosure will no longer perform its intended containment function (A95 ROP
? 9-66a).
2) The exception was written to allow such installations only at the top of the
enclosure as the panel noted this limitation would assure that the outer raceway
termination wouldn?t be readily accessible (A98 ROC ? 9-44).
3) The current language not only requires the fitting to remain accessible, but
also requires that the enclosure be surface-mounted.
Adequate closure of the enclosure is dependent upon adequate closure of the
raceway. No fittings are designed and evaluated to close openings around
multiple cables as anticipated by the proposal. The lack of suitable fittings
presents the possibility that excess dust, debris, rodents or other pests could.......

​

​

 

[dnem]

I personally don't see why it should be allowed to install an 18" length of PVC conduit out of the top of a recessed panel and have the NM cable fed into the conduit. There is no reason that you can't install NM connector into the top of the recessed enclosure and attached the cables properly. The exception for the use of a conduit on a surface mount panel makes sense due to a couple of factors including, protection from physical damage and the requirement in 334.10(3).

They allow more than 18". . They allow 10'.

As for the requirement for #6 wire to be identified by a continious white or grey color, my 1978 NEC requires #6 or smaller to be identified by a continious white or grey color.

I was going by memory. . I have a fantastic memory. . The only problem is that it's short.

I enforce the code as written and don't try to pick and choose what to enforce and what not to enforce, or change the rules to make them fit what I want to do.

Did you ever see the Mike Holt video where he had a panel of inspectors from thruout the country and every single guy on the panel said the surface mounted spec wasn't enforced in his jurisdiction ? . Even Mike himself said the surface mounted spec didn't make any sense.

David

 

[raider1]

Here is my point.

As an inspector, I am required to enforce the NEC as written. My own feelings and opinions about what code sections I agree with and what code sections I don't agree with shouldn't interfere with me performing my job. If I don't agree with a code section or want to change a code section then I will submit a code change purposal.

Chris