334.30 requirements

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I sat for my first journeyman license at a test under the 1965 NEC.

Back then, NM was in 336, and the support rule was in 336-5:
1965 NEC
336-5. Supports. Nonmetallic sheathed cable shall be secured by approved staples, straps, or similar fittings, so designed and installed as not to injure the cable. Cable shall be secured in place at intervals not exceeding 4 1/2 feet and within 12 inches from every cabinet, box or fitting, except that in concealed work in finished buildings or finished panels for prefabricated buildings where such supporting is impracticable, the cable may be fished between points of access.
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The key phrase is essentially identical to today's 2014 NEC 334.30
 
al hildenbrand said:
I sat for my first journeyman license at a test under the 1965 NEC.

Back then, NM was in 336, and the support rule was in 336-5:


The key phrase is essentially identical to today's 2014 NEC 334.30
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Curious, what were you taught or what did you think the rule required back in 1968 under the 1965 code cycle. Do you know what they are teaching journeyman today on the subject?
 
peter d said:
Even with loops (of a reasonable length) being made, is anyone really observing problems with this? :huh:
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No -- I don't think it is an issue. The issue is the interpretation. I did get turned down because I had a staple 13" from the recessed can but that was 30 years ago. It was 24" trusses with the can's jb out toward the middle. I laughed and told him I wasn't going to change a staple for 1". It passed....LOL
 
david said:
We do not dismiss quickly generations of our piers understanding of a particular section no more than we dismiss hastily an electrician’s point of view.
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But you will dismiss the people who write the code when it is not what you want to believe.
 
Thanks for posting the ROP, Bob. I would like to think I had a little backing for all those years I enforced service loops at recessed cans at the end of my bayonet. I see it as code compliant, and taking care of the next guy so that the wire can be pulled out and examined or added to without a well trained ferret. :)

ETA: I will likely continue to recommend installing the chime transformer connected to the furnace as well, and I know that is forbidden by code. Tradition marches on. :D
 
david said:
Curious, what were you taught or what did you think the rule required back in 1968 under the 1965 code cycle. Do you know what they are teaching journeyman today on the subject?
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I apprenticed at the side of my old Master, Paul Denny, and he taught me that it was about the length of the NM. The teaching was entirely hands on, with verbal back and forth, as I was his only employee. I read the NEC on my own.

I don't know what today's journeymen are taught.

Frankly, I hadn't paid attention to the actual language of the printed words of 334.30 until this thread. . . I'm still pulling rope and I still feel my first Master's guidance. Your raising this question, David, has been an eye opener.
 
iwire said:
But you will dismiss the people who write the code when it is not what you want to believe.
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Bob,
Not quickly,
334.30 (B) Unsupported Cables. Nonmetallic-sheathed cable shall be permitted to be unsupported where the cable:
(1) Is fished between access points through concealed spaces in finished buildings or structures and supporting is impracticable.
(2) Is not more than 1.4 m (41/2 ft) from the last point of cable support to the point of connection to a luminaire or other piece of electrical equipment and the cable and point of connection are within an accessible ceiling.

“Section 334.30(B)(2) permits short, unsupported lengths of nonmetallic-sheathed cable for luminaire and equipment connections.” NFPA 70 / 2008 handbook

I / we would first have to get a comment on the section as a whole is the thrust of 334.30 staple placement or limiting unsecured lengths of NMB?
 
Perhaps we are not talking about the same situation. IMO, 334.30(C) requires at least 12" for boxes that are integral with a device. This is could be in areas such as trailers where the receptacle and box is an integral unit. There must be the 12" loop in order for the box to be worked on properly. Also, there are recessed cans where the box is integral with the fixture enclose as in some wac fixtures. Here you need at least a 12" loop-- we just did some of these and there is no way to service them without the loop.

The way I read the proposal was that the submitter was trying to get the proposal for fixtures as well. There was no need so the cmp said that it was already in place. They are not clear about the specifics. Halo recessed cans do not need a service loop as the box is accessible thru the opening. IMO, there is no allowance for more than 12" of cable between the staple and the box. In that same section 334.30, by many people's interpretation, we could leave large loops of wire between the 4'6" distance between staples. Seriously, if you were an inspector would you allow 3' loops between staples?

I can say this with certainty, NC will not allow it- although some inspectors may- I had our state engineering dept look at this thread and he agrees with me...FWIW

This can be easily rectified if the cmp had written: "measured along the cable."
 
Dennis Alwon said:
Perhaps we are not talking about the same situation. IMO, 334.30(C) requires at least 12" for boxes that are integral with a device. This is could be in areas such as trailers where the receptacle and box is an integral unit. There must be the 12" loop in order for the box to be worked on properly. Also, there are recessed cans where the box is integral with the fixture enclose as in some wac fixtures. Here you need at least a 12" loop-- we just did some of these and there is no way to service them without the loop.

The way I read the proposal was that the submitter was trying to get the proposal for fixtures as well. There was no need so the cmp said that it was already in place. They are not clear about the specifics. Halo recessed cans do not need a service loop as the box is accessible thru the opening. IMO, there is no allowance for more than 12" of cable between the staple and the box. In that same section 334.30, by many people's interpretation, we could leave large loops of wire between the 4'6" distance between staples. Seriously, if you were an inspector would you allow 3' loops between staples?

I can say this with certainty, NC will not allow it- although some inspectors may- I had our state engineering dept look at this thread and he agrees with me...FWIW

This can be easily rectified if the cmp had written: "measured along the cable."
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Yes I would on lights. 3' bent back on itself or a U-loop is less than 18" either way from staple to can. Even 14/2 is stiff enough to hold that cable length indefinitely. iow, if I position that in a ceiling half way between the drywall below and subfloor above, one would have to be incredibly unobservant to smack the cable with a power tool.

Frequently what I do is leave a loop then put a second staple or support within 12" of the can, so that there is workable cable length if needed if one removes a staple. I dont pull banjo strings (straight line distance) to the fixture or fan that makes installing anything in the future impossible without a hidden splice or interconnect device, which many electricians hate.

As before, that 334.30(C) requires a 12" service loop but B prohibits it makes zero sense. The only time where they possibly arent permitted is in exposed construction where the NM must closely follow the surface of the building.
 
FWIW I do a lot of residential work, and I see a lot of others work as well. I don't leave loops and I don't see them being left in my area.
 
JFletcher said:
As before, that 334.30(C) requires a 12" service loop but B prohibits it makes zero sense. The only time where they possibly arent permitted is in exposed construction where the NM must closely follow the surface of the building.
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IMO, you are not understanding the difference between (B) and (C). They are talking about different scenarios.

Anyway, you can't just allow a 4' loop for a recessed can that does not need a service loop and then not allow it anywhere else with your reasoning of the code. That's my opinion... Obviously, we are going to agree to disagree.
 
Dennis Alwon said:
I am using the 4' because nm must be stapled every 4'-- so the rule for a staple 12" from a box is assinine if 4' is allow to be looped.
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Every 4 1/2 feet.

334.30 Securing and Supporting. Nonmetallic-sheathed
cable shall be supported and secured by staples, cable ties,
straps, hangers, or similar fittings designed and installed so
as not to damage the cable, at intervals not exceeding 1.4 m
(4 1⁄2 ft) and within 300 mm (12 in.) of every outlet box,
junction box, cabinet, or fitting. Flat cables shall not be
stapled on edge.
 
Dennis Alwon said:
I am using the 4' because nm must be stapled every 4'-- so the rule for a staple 12" from a box is assinine if 4' is allow to be looped.
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I agree, I see it as asinine too.

BUT, the CMP clearly stated it's allowed.

Please go back and look at the ROP I posted, the panel statement is aimed at all of 334.30, not just one of the subsections.
 
iwire said:
I agree, I see it as asinine too.

BUT, the CMP clearly stated it's allowed.

Please go back and look at the ROP I posted, the panel statement is aimed at all of 334.30, not just one of the subsections.
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Bob, both I and our state engineer read it independently and disagree with you as to what the cmp is saying. I believe their response is to (C) where it is allowed to have more than 12" under the scenario where the box is part of the luminaire and you need the service loop.

Anyway, we will, of course bring it up at our annual meeting for whatever it is worth
 
Dennis Alwon said:
Bob, both I and our state engineer read it independently and disagree with you as to what the cmp is saying. I believe their response is to (C) where it is allowed to have more than 12" under the scenario where the box is part of the luminaire and you need the service loop.

Anyway, we will, of course bring it up at our annual meeting for whatever it is worth
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Dennis, you and your state engineer are looking at the "Recommendation" but rather focusing on a simile in the "Substantiation". The Proposal submitted by Steve Carle is for (look at the ROP) 334.30. The Proposal is NOT for 334.30(C).

To be clear, the Substantiation opens with a simile, "Just like. . . a service loop. . . in 334.30(C)." This simile compares the service loop described in 334.30(C) to the result of the Proposed NEW phrasing of 334.30.

The Panel Statement is about the Proposed NEW phrasing of 334.30. That is because the Recommendation is to CHANGE the phrasing of 334.30.

And the Panel Statement says, "The loop proposed by the submitter is not prohibited in the current language of this section and 334.30 only requires that the cable be supported within 12 in. of the outlet box, junction box, cabinet, or fitting."

Dennis, to claim that the CODE MAKING Panel Statement is about 334.30(C) to the exclusion of the general rule of 334.30 is glaringly wrong.
 
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Dennis Alwon said:
Bob, both I and our state engineer read it independently and disagree with you as to what the cmp is saying. I believe their response is to (C) where it is allowed to have more than 12" under the scenario where the box is part of the luminaire and you need the service loop.

Anyway, we will, of course bring it up at our annual meeting for whatever it is worth
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Respectfully I think you are both trying not to read what it says.
 
Again I ask - is this really a big problem that has a documented, verifiable hazard? :?:? Or is it just good fodder for forum debates?
 
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