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  1. #1
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    Default Too Many wires in a conduit.

    All the branch wires from this panel in the garage are stuffed into this conduit.
    It looks like there are too many wires in here. What type of Problems can arise under this condition?

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    Default Re: Too Many wires in a conduit.

    Ken,

    It is not correct, but first a question - how long is the piece of conduit? That's not shown.

    And I'll make a guess at the length - 8 ft ceiling, top of panel is about 1 ft down, conduit goes through ceiling into attic a sticks up maybe 6 in for a total length of 1-1/2 to 2 ft ... is that about right.

    Jerry Peck
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    Default Re: Too Many wires in a conduit.

    I wouldn't call that out.


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    Default Re: Too Many wires in a conduit.

    Quote Originally Posted by Roy Lewis View Post
    I wouldn't call that out.
    Roy,

    You probably see that all the time?

    I always thought it was a "Florida" electricians thing, that other electricians knew better ... now I see that either a Florida electrician moved up there, or the practice was much more widespread than I thought it was.

    Jerry Peck
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    Default Re: Too Many wires in a conduit.

    Quote Originally Posted by Jerry Peck View Post
    Ken,

    It is not correct, but first a question - how long is the piece of conduit? That's not shown.

    And I'll make a guess at the length - 8 ft ceiling, top of panel is about 1 ft down, conduit goes through ceiling into attic a sticks up maybe 6 in for a total length of 1-1/2 to 2 ft ... is that about right.
    Not sure how long, but your guess sounds about right. After it enters the basement the wires are exposed

    Ken Amelin
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    Default Re: Too Many wires in a conduit.

    Quote Originally Posted by Jerry Peck View Post
    Ken,

    It is not correct, but first a question - how long is the piece of conduit? That's not shown.

    And I'll make a guess at the length - 8 ft ceiling, top of panel is about 1 ft down, conduit goes through ceiling into attic a sticks up maybe 6 in for a total length of 1-1/2 to 2 ft ... is that about right.
    Quote Originally Posted by Ken Amelin View Post
    Not sure how long, but your guess sounds about right. After it enters the basement the wires are exposed
    The main things would be conduit fill and each NM cable is not secured to the enclosure.

    If the length is 24 inches or less, then derating does not apply, that would be the main issue (overheating) if longer than 24" as the code allows for 'bundling'/'lack of maintaining spacing' for up to 24".

    I always put it in my reports even though I knew it would never be addressed ... *I* did not want to be the tone to address it as some point in the future simply because *I* didn't put it in my reports. I think it is prudent to put things like that in your report, even though you are likely well aware that those things will never be corrected.

    Jerry Peck
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    Default Re: Too Many wires in a conduit.

    Each cable does not need to be secured to the enclosure if installed as shown. They do need to be secured near the top of the sleeve. There are specific requirements beside the panel being surface mounted to be met before an installation like that is allowed by code. One is a minimum sleeve length.

    All answers based on unamended National Electrical codes.

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    Default Re: Too Many wires in a conduit.

    Quote Originally Posted by Ken Amelin View Post
    All the branch wires from this panel in the garage are stuffed into this conduit.
    It looks like there are too many wires in here. What type of Problems can arise under this condition?
    The fill percentage for short nipples, less than 24 inches long, is different than a longer conduit but there is a limit. That limit is 60%. I will bet you a dollar to the hole in a doughnut that fill is over 60%.

    US NEC Chapter Nine.
    Notes to Tables
    "(4) Where conduit or tubing nipples having a maximum length not to exceed 600 mm (24 in.) are installed between boxes, cabinets, and similar enclosures, the nipples shall be permitted to be filled to 60 percent of their total cross-sectional area, and 310.15(B)(3)(a) adjustment factors need not apply to this condition."

    That is especially true when you remember that cables which are not round are calculated as if they are round by using the largest dimension of their cross section as the diameter of the circular dimension.
    "A multiconductor cable, optical fiber cable, or flexible cord of two or more conductors shall be treated as a single conductor for calculating percentage conduit fill area. For cables that have elliptical cross sections, the cross-sectional area calculation shall be based on using the major diameter of the ellipse as a circle diameter."

    If I understand the situation correctly there is another problem in addition to the fill of that conduit. I believe that the US NEC requires that cables leaving a conduit do that through a fitting designed for the purpose. Passing out through a connector capped with a bushing would not seen to be compliant with:

    300.16 Raceway or Cable to Open or Concealed Wiring.
    (A) Box, Conduit Body, or Fitting. A box, conduit body, or terminal fitting having a separately bushed hole for each conductor shall be used wherever a change is made from conduit, electrical metallic tubing, electrical nonmetallic tubing, nonmetallic-sheathed cable, Type AC cable, Type MC cable, or mineral-insulated, metal-sheathed cable and surface raceway wiring to open wiring or to concealed knob-and-tube wiring. A fitting used for this purpose shall contain no taps or splices and shall not be used at luminaire outlets. A conduit body used for this purpose shall contain no taps or splices, unless it complies with 314.16(C)(2).
    If a box was installed at the end of that nipple with all of the cables attached using cable connectors that would make a pretty neat job of it. You could then remove all the sheaths from the Type NM (Romex) cable and run the conductors down into the panel cabinet for termination. That would also bring the conduit fill back under 60%.

    --
    Tom Horne

    Last edited by THOMAS HORNE; 08-01-2019 at 12:33 PM. Reason: Left out a reference

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    Default Re: Too Many wires in a conduit.

    Observation: Too Many wires in a conduit, or nipple.
    Recommend: A licensed electrical contractor take the appropriate steps to increase cable clearance.

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    Cool Re: Too Many wires in a conduit.

    Quote Originally Posted by Ken Amelin View Post
    All the branch wires from this panel in the garage are stuffed into this conduit.
    It looks like there are too many wires in here. What type of Problems can arise under this condition?
    I don't see anything wrong with the wires running in the raceway. It's a pretty neat panel. I did notice that the service entrance neutral is not color coded Now I see the white stripe...ma bad

    Last edited by mary theresa craig; 08-07-2019 at 02:40 AM.

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    Default Re: Too Many wires in a conduit.

    Quote Originally Posted by Ken Amelin View Post
    All the branch wires from this panel in the garage are stuffed into this conduit.
    It looks like there are too many wires in here. What type of Problems can arise under this condition?
    If you're a code inspector you may fail this, but to answer your question, no problems are likely. The consideration is strictly thermal. Electrically, it is impossible to put more current through the bunch than the main breaker will allow.
    A case can be made that at max current the wires will run hotter than if less packed, and if the PVC were long enough it might become an issue - even then, only at the extreme. Statistically, and realistically, that would be a difficult argument to make.


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    Default Re: Too Many wires in a conduit.

    Electrically, it is impossible to put more current through the bunch than the main breaker will allow.
    You are relating to ampacity of all to the ampacity rating of the main?

    Trying to follow your reasoning for that?

    Jerry Peck
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    Default Re: Too Many wires in a conduit.

    NEC Ch. 9 Table 1 maximum fill for conduit is 40% when it contains more than 2 conductors. There are many other places in the NEC speaking to this. You can adjust the capacity of the conductor in Table 310.15(B)3a multiply by 80% to 35% When you have over 4 conductor.


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    Default Re: Too Many wires in a conduit.

    Quote Originally Posted by Phillip Condreay View Post
    NEC Ch. 9 Table 1 maximum fill for conduit is 40% when it contains more than 2 conductors. There are many other places in the NEC speaking to this. You can adjust the capacity of the conductor in Table 310.15(B)3a multiply by 80% to 35% When you have over 4 conductor.
    Read Note 4 of the notes to tables right at the front of Chapter 9. You will find that in nipples between enclosures which do not exceed 24 inches in length the fill increases to 60%.

    US NEC Chapter Nine.
    Notes to Tables
    "(4) Where conduit or tubing nipples having a maximum length not to exceed 600 mm (24 in.) are installed between boxes, cabinets, and similar enclosures, the nipples shall be permitted to be filled to 60 percent of their total cross-sectional area, and 310.15(B)(3)(a) adjustment factors need not apply to this condition."

    The photos do not show what is at the top of that nipple but if it is just a bushed connector I do not think it meets the requirements of 300.16 viz.

    "300.16 Raceway or Cable to Open or Concealed Wiring.
    (A) Box, Conduit Body, or Fitting. A box, conduit body, or terminal fitting having a separately bushed hole for each conductor shall be used wherever a change is made from conduit, electrical metallic tubing, electrical nonmetallic tubing, nonmetallic-sheathed cable, Type AC cable, Type MC cable, or mineral-insulated, metal-sheathed cable and surface raceway wiring to open wiring or to concealed knob-and-tube wiring. A fitting used for this purpose shall contain no taps or splices and shall not be used at luminaire outlets. A conduit body used for this purpose shall contain no taps or splices, unless it complies with 314.16(C)(2)."

    If a box were installed at the end of that nipple with all of the cables attached using cable connectors that would make a pretty neat job of it. You could then remove all the sheaths from the Type NM (Romex) cable and run the conductors down into the panel cabinet for termination. That would also bring the conduit fill back under 60%.

    --
    Tom Horne


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    Default Re: Too Many wires in a conduit.

    @Tom Horne,

    You keep citing an article that does not always apply. There are specific conditions where the cables are not required to be clamped to the enclosure and are allowed as shown. Other conditions do apply.

    All answers based on unamended National Electrical codes.

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    Default Re: Too Many wires in a conduit.

    For an article 300 section to not apply it would have an exception and/or a reference to a section for a specific section which covers the condition were it does not apply. That section would have language such as "Not with standing article 300.16..." If you know of an exception or another section which allows coming out of EMT with cables that do not comply with 300.16 then please refer to it for the sake of all of out educations.

    No matter how common a practice is it can still be a code violation. For years it was very common practice use the reduced sizes of Service Entry Conductors for dwellings on feeders that supplied only a portion of the dwelling. Recent changes in the wording of the code have made it more clear that that practice is not compliant with the exception that allows reducing the size of dwelling feeders. The other practice along the same line was the use of 4/? service entry cable to bring power to each of 2 service disconnecting means where each served only a Portion of the dwelling supplied through those 2 separate service disconnects. The practice had been ongoing for more than 2 decades even in the face of a request for formal interpretation which was answered in the negative.

    Please give us something to hang our hat on when the electrical inspector says that is a violation of 300.16. I've been there. I bought the T shirt and the hat. I have no interest in going there again.

    --
    Tom Horne

    Last edited by THOMAS HORNE; 08-08-2019 at 08:11 AM. Reason: To separate sections

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    Default Re: Too Many wires in a conduit.

    All answers based on unamended National Electrical codes.

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    Default Re: Too Many wires in a conduit.

    Quote Originally Posted by THOMAS HORNE View Post
    You could then remove all the sheaths from the Type NM (Romex) cable and run the conductors down into the panel cabinet for termination.
    You have said that a couple of times, but I have not found anything in the code which allows that practice.

    I know some do it, but NM cable is listed as NM cable ... "cable" ... not single conductors. Once the cable is stripped off and the conductors are run down in a raceway, it is no longer being used as NM cable, it is being used as single conductors - which it is not.

    Please provide a code section or listing information which allows you to strip the outer sheath off NM cable and use it as individual conductors.

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    Default Re: Too Many wires in a conduit.

    Quote Originally Posted by Jerry Peck View Post
    You have said that a couple of times, but I have not found anything in the code which allows that practice.

    I know some do it, but NM cable is listed as NM cable ... "cable" ... not single conductors. Once the cable is stripped off and the conductors are run down in a raceway, it is no longer being used as NM cable, it is being used as single conductors - which it is not.

    Please provide a code section or listing information which allows you to strip the outer sheath off NM cable and use it as individual conductors.
    Interesting comment Jerry, but aren't all the conductors in every panel nothing but stripped NM cable? I would like to rephrase your question and ask not where the code says you can use it, but I would ask where in the code it says you can't use it.

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    Default Re: Too Many wires in a conduit.

    Quote Originally Posted by Ken Amelin View Post
    Interesting comment Jerry, but aren't all the conductors in every panel nothing but stripped NM cable?
    "in a panel" and "in a raceway" are different animals.

    One, "in a panel", the stripped back sheath and conductors are already in their final enclosure where they are terminated.

    The other, "in a raceway" is 'part of the circuit in which NM cable ... CABLE ... is the wiring method', except that it is no longer "Nonmetallic" (NM) "Sheathed" "Cable" as it is no longer being used as a "cable", and there is no "sheath" over the conductors, "nonmetallic" or otherwise.

    Quote Originally Posted by Ken Amelin View Post
    I would like to rephrase your question and ask not where the code says you can use it, but I would ask where in the code it says you can't use it.
    - Part I. General
    - - 334.1 Scope. This article covers the use, installation, and construction specifications of nonmetallic-sheathed cable.
    - - 334.2 Definitions.
    - - - Nonmetallic-Sheathed Cable. A factory assembly of two or more insulated conductors enclosed within an overall nonmetallic jacket.
    - - (Jerry's comment: Once the jacket is removed outside the enclosure it is terminated in, it is no longer a cable and no longer meets the definition of nonmetallic-sheathed cable.)

    - Part II. Installation
    - - 334.10 Uses Permitted. Type NM, Type NMC, and Type NMS cables shall be permitted to be used in the following, except as prohibited in 334.12.
    - - (Jerry's comment: Once the jacket is removed outside the enclosure it is terminated in, it is no longer nonmetallic-sheathed cable, thus it is not covered by Uses Permitted.)

    - Part III. Construction Specifications
    - - 334.100 Construction. The outer cable sheath of nonmetallic-sheathed cable shall be a nonmetallic material.
    - - 334.116 Sheath. The outer sheath of nonmetallic sheathed cable shall comply with 334.116(A), (B), and (C).
    - - - (A) Type NM. The overall covering shall be flame retardant and moisture resistant.
    - - - (B) Type NMC. The overall covering shall be flame retardant, moisture resistant, fungus resistant, and corrosion resistant.
    - - - (C) Type NMS. The overall covering shall be flame retardant and moisture resistant. The sheath shall be applied so as to separate the power conductors from the communications conductors.
    - - (Jerry's comment: Strip off the outer sheath before the enclosure where the NM cable terminates and you no longer meet 334.116(A), (B), and (C).)

    Once you remove the outer sheath outside the enclosure it is terminating in you no longer have nonmetallic sheathed cable as the wiring method, you have single conductors which are not identified or listed for any use (no longer listed for any electrical use ... I suppose you could use them as heavy duty twist-ties, a bit awkward, but should work for that).

    Think a little bit about the above, go back up to 334.116(C) if you need to ... now strip off that outer sheath ... still have any doubts as to what I am saying about stripping off the outer sheath?

    Oh ... you don't mean NM cable any more, do you? You meant to say 'I am only specifically referring to Type NM only, not the other types of NM cable.' ... Really? I suspect you are thinking that way, but I doubt you will admit to it here and followup stating 'yeah, I meant Type NM ONLY, not ALL NM cable'.

    Being sarcastic? No.

    Incredulous that one would think that way? YES!

    Jerry Peck
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    Default Re: Too Many wires in a conduit.

    Think of it this way:

    Would you consider it okay to sand a section if CPVC 'a little smaller' so you could fit it through a too-small hole?

    You would be jumping all over me if I said 'show me the code where it says that is not allowed'.

    You would consider it one of those things which are so obvious that the code doesn't need to tell you to 'point the barrel of the hand gun away from yourself before pulling the trigger'.

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    Default Re: Too Many wires in a conduit.

    Quote Originally Posted by Jerry Peck View Post
    You have said that a couple of times, but I have not found anything in the code which allows that practice.

    I know some do it, but NM cable is listed as NM cable ... "cable" ... not single conductors. Once the cable is stripped off and the conductors are run down in a raceway, it is no longer being used as NM cable, it is being used as single conductors - which it is not.

    Please provide a code section or listing information which allows you to strip the outer sheath off NM cable and use it as individual conductors.
    Jerry

    It is customary to quote the whole suggestion and not just half of it when you are trying to refute an idea that someone has put forward viz.

    "If a box were installed at the end of that nipple with all of the cables attached using cable connectors that would make a pretty neat job of it. You could then remove all the sheaths from the Type NM (Romex) cable and run the conductors down into the panel cabinet for termination. That would also bring the conduit fill back under 60%."

    Now taken as a whole what is wrong with what I said? Is it that the individual conductors are not marked with their type and listing? I'll buy that completely but I have purchased type NM cable were that was not the case. I cannot tell you which brand or even why they did it but I have seen Type NM cable with individually marked conductors in the jacket. But OK I'll give you that is a rather rare case. So if I were faced with unmarked conductors I would put barrier strips in the back of the box; your not going to say that I haven't assured you that the box is large enough for the space required for all of those conductors are you?; and change over to individual listed single conductors for the current carrying conductors. I'd also save some effort by installing a Equipment Grounding Conductor bus bar in the upper box or trough and bringing a single green coded wire, sized for the panelboard main breaker, down into the panelboard cabinet.

    What can I say gals and guys? It just looks wrong to me. See my answer to another post for what section I have been referred to that does, I think, prohibit the installation as shown.

    Also let me apologize again for my gross misapplication of 300.16.

    --
    Tom Horne

    Last edited by THOMAS HORNE; 08-08-2019 at 07:27 PM.

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    Default Re: Too Many wires in a conduit.

    Quote Originally Posted by Jim Port View Post
    I don't see how your example applies to NM cables being terminated in the Cabinet of a Panelboard.

    That said I do see that you were right in saying that 300.16 did not apply. I was completely misreading it. I was wrong!

    The section that someone on the Mile Holt NEC forum board pointed me to which does seem to apply would be 312.5(C) Exception: viz.

    "312.5 Cabinets, Cutout Boxes, and Meter Socket Enclosures.
    Conductors entering enclosures within the scope of this article shall be protected from abrasion and shall comply with 312.5(A) through (C).

    (C) Cables. Where cable is used, each cable shall be secured to the cabinet, cutout box, or meter socket enclosure.
    Exception: Cables with entirely nonmetallic sheaths shall be permitted to enter the top of a surface-mounted enclosure through one or more nonflexible raceways not less
    than 450 mm (18 in.) and not more than 3.0 m (10 ft) in length, provided all of the following conditions are met:
    (a) Each cable is fastened within 300 mm (12 in.), measured along the sheath, of the outer end of the raceway.
    (b) The raceway extends directly above the enclosure and does not penetrate a structural ceiling.
    (c) A fitting is provided on each end of the raceway to protect the cable(s) from abrasion and the fittings remain accessible after installation.
    (d) The raceway is sealed or plugged at the outer end using approved means so as to prevent access to the enclosure through the raceway."

    Is anybody going to help me out by telling me what an approved means is "to prevent access to the enclosure through the raceway."

    "(e) The cable sheath is continuous through the raceway and extends into the enclosure beyond the fitting not less than 6 mm (1⁄4 in.).
    (f) The raceway is fastened at its outer end and at other points in accordance with the applicable article.
    (g) Where installed as conduit or tubing, the cable fill does not exceed the amount that would be permitted for complete conduit or tubing systems by Table 1 of Chapter 9 of this Code and all applicable notes thereto.

    Informational Note: See Table 1 in Chapter 9, including Note 9, for allowable cable fill in circular raceways. See 310.15(B)(3)(a) for required ampacity reductions for multiple cables installed in a common raceway
    ."

    The underlining is mine.

    What I see in the OPs photograph is that the raceway shown does penetrate a structural ceiling. That is what I think is this installations fatal flaw. The cable fill has been exceeded radically. I'd even be willing to bet a dollar to the hole in a doughnut that some of those conductors are now carrying more than they can carry if they were properly derated.

    By the way I have seen this type of thing done but I had only seen it were it was used to get the cables above the height were they would be subject to physical damage, above the suspended ceilings of manufactured buildings and warehouses being converted to offices.

    --
    Tom Horne


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    Default Re: Too Many wires in a conduit.

    Quote Originally Posted by THOMAS HORNE View Post
    It is customary to quote the whole suggestion and not just half of it when you are trying to refute an idea that someone has put forward viz.
    Tom,

    It is common, at least on this board, to only quote what one is referring to so that readers do not have to read through an entire quoted post to read one part of it.

    It's worked that way here for a very long time (with a few exceptions, there are some who quote an entire long post while they are only referring to a couple of lines in it ... makes it vary cumbersome for readers when that is done.

    - - - Updated - - -

    Quote Originally Posted by THOMAS HORNE View Post
    "If a box were installed at the end of that nipple with all of the cables attached using cable connectors that would make a pretty neat job of it. You could then remove all the sheaths from the Type NM (Romex) cable and run the conductors down into the panel cabinet for termination. That would also bring the conduit fill back under 60%."

    Now taken as a whole what is wrong with what I said? Is it that the individual conductors are not marked with their type and listing? I'll buy that completely but I have purchased type NM cable were that was not the case.
    Tom,

    That is part of it.

    Even if the inside conductor were labeled individually within the outer sheath, removing the outer sheath makes it no longer NM cable as the wiring method, as I posted with the code sections.

    Jerry Peck
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    Default Re: Too Many wires in a conduit.

    Quote Originally Posted by Jerry Peck View Post
    Tom,

    That is part of it.

    Even if the inside conductor were labeled individually within the outer sheath, removing the outer sheath makes it no longer NM cable as the wiring method, as I posted with the code sections.
    Jerry

    I buy that it would no longer be NM cable. If the individual conductors were listing marked as whichever conductor type they are; say THHN; then if you read what I was suggesting it does not need to remain NM if that NM cable has been connected to a box, which is sized for the number of conductors, and continues through that box and the conduit between that box and the panel as THHN. I freely admit that NM cable with individually listing marked conductors is probably rather rare but I have encountered it more than once.

    As I said if the wire is not listing marked I would connect it to listing marked individual conductors by using barrier strips with sems screws. That way the inspector would not need to be concerned about solid wire terminating under the screw without a crimp on terminal. Yes I would use listed barrier strips.

    --
    Tom Horne


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    Default Re: Too Many wires in a conduit.

    Tom,

    One does not change the conductors in "NM cable" to "not NM cable conductors" by removing the outer sheath, regardless what the conductors are, are not, individually marked as.

    You make that change in a junction box by cutting the NM cable off there and attaching to individually listed and labeled conductors with the appropriate wire connectors.

    Remember, NM cable is: a) manufactured as a cable; has an outer nonmetallic sheath.

    Make a cable on site by putting conductors inside some type of sheath does not make that "cable" nor does it make it "NM" anything.

    Conversely, stripping off the outer sheath does not make the conductors in NM cable into individual conductors ... but it does make the NM cable no longer NM cable when it is outside the enclosure it terminates in.

    Are you saying you could remove the outer sheath from NM-S? That IS a type of NM cable?

    Jerry Peck
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    Default Re: Too Many wires in a conduit.

    Quote Originally Posted by Jerry Peck View Post
    Tom,

    Are you saying you could remove the outer sheath from NM-S? That IS a type of NM cable?
    NO I'm not. It wouldn't matter what type the cable is UNLESS the individual conductors are type marked as individual conductors such as THHN. That sometimes occurs when a cable manufacturer makes both cable and listed single conductors in the same facility. I imagine that occurs when there is an imbalance between stock on hand and the present level of demand for each type of product but it could be just for efficiency so that the manufacturer would not need to make 2 different types of individual wires. In the cases were the individual wires are listed type marked conductors ONLY you could run those wires in conduit without the cable sheath because the listed and type marked individual conductors do not stop being listed individual conductors when the cable sheath is removed from around them.

    I acknowledge that this is not true of the majority of Non Metallic cable. But I also assert that it is true of some. The use of individually listed conductors is far more common in the manufacture of Metal Clad (Type MC) cable than it is for Non Metallic (Type NM). If I strip the jacket off of most NM cable I will no longer have listed cable and I also will not have listed wires. My point is that is not universally true. Some cables are made with individual listed wires and the wires are appropriately marked to reflect there individual listed status. You keep saying that taking unmarked wires out of cable does not make them listed wires and that is true. But the reversed condition is also true in that removing individually listed and labeled conductors from a cable does not void their Listing and Labeling. Those listed and labeled conductors can still be used in any manner which is appropriate to the Listing and Labeling of the wires.

    --
    Tom Horne


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    Default Re: Too Many wires in a conduit.

    Quote Originally Posted by THOMAS HORNE View Post
    You keep saying that taking unmarked wires out of cable does not make them listed wires and that is true. But the reversed condition is also true ...
    No, that last part is not true as has been described.

    But this would be as long as ...

    ... in that removing individually listed and labeled conductors from a cable does not void their Listing and Labeling. Those listed and labeled conductors can still be used in any manner which is appropriate to the Listing and Labeling of the wires.
    ... as long as the individually labeled and listed conductors were completely removed from the outer sheath, end to end, and were no longer 'part of an installed labeled and listed cable assembly'.

    As long as the conductors are 'part of a labeled and listed cable assembly', then no, then individual listed and labeled conductors are not allowed to have the outer sheath stripped off a length of the cable and those individually listed and labeled conductors are not to be treated as individual conductors.

    Go back to the code sections for NM cable construction that I posted - you should be able to clearly see why.

    Jerry Peck
    Construction/Litigation/Code Consultant - Retired
    www.AskCodeMan.com

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    Default My post adds zero to the discussion but...

    Two different electricians worked on this panel, and the guy who worked on the right portion was older.


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    Default Re: Too Many wires in a conduit.

    You guys crack me up! All sheathing Weather it be non metallic,metallic Flex ,metallic rigid... Is required to be continuous all the way to its enclosure where it then terminates through a clamp which secures The Wire to the enclosure. If the sheathing is removed before the wire enters the enclosure well guess what , you're running new wire or you're installing a junction box and accessible junction box. PS if all the sheathing was removed before the wire was even put your the Raceway I would not want to be the one wiring that panel box


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    Default Re: Too Many wires in a conduit.

    Quote Originally Posted by mary theresa craig View Post
    PS if all the sheathing was removed before the wire was even put your the Raceway I would not want to be the one wiring that panel box
    IF ... a big IF ... the individual conductors were properly marked, labeled, and listed as individual conductors and were removed from the outer sheath BEFORE the wires were pulled into a raceway WHICH WENT ALL THE WAY from Point A to Point B, then that would not be any different than if THHN/THWN conductors were installed in a raceway ... hopefully the electrician pulling the wires in keeps them paired together and labeled.

    One advantage of NM cable is that, in the enclosure, all the conductors of that circuit (the NM cable) can easily be traced back to the NM sheath sticking through the clamp, making it easy to identify the grounded conductor and hot conductor of the same circuit.

    But starting out as NM cable and ending up as ... well ... 'not NM cable' going through a raceway (because they are not individual conductors) is not good.

    Keep in mind the construction of NM cable, and the reasons for such construction, and none say that the outer sheath may be removed at any given point if the electrician feels like it.

    Jerry Peck
    Construction/Litigation/Code Consultant - Retired
    www.AskCodeMan.com

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    Default Re: Too Many wires in a conduit.

    You don't get to change wiring methods by stripping the sheath off of NM-B cable.

    Wiring methods need to be complete end to end. If the conduit isn't attached to a box on the non-panel end to, it is not a conduit (or tube) wiring method but is just a sleeve, and you can't change wiring methods in a sleeve. This is made pretty clear several places, 300.3 (A) is one

    Occam's eraser: The philosophical principle that even the simplest solution is bound to have something wrong with it.

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    Default Re: Too Many wires in a conduit.

    Bill,

    I thought he would 'get it' when I posted this earlier in the thread:

    Quote Originally Posted by Jerry Peck View Post
    - Part III. Construction Specifications
    - - 334.100 Construction. The outer cable sheath of nonmetallic-sheathed cable shall be a nonmetallic material.
    - - 334.116 Sheath. The outer sheath of nonmetallic sheathed cable shall comply with 334.116(A), (B), and (C).
    - - - (C) Type NMS. The overall covering shall be flame retardant and moisture resistant. The sheath shall be applied so as to separate the power conductors from the communications conductors.
    .
    .
    .
    Think a little bit about the above, go back up to 334.116(C) if you need to ... now strip off that outer sheath ... still have any doubts as to what I am saying about stripping off the outer sheath?

    Oh ... you don't mean NM cable any more, do you? You meant to say 'I am only specifically referring to Type NM only, not the other types of NM cable.' ... Really? I suspect you are thinking that way, but I doubt you will admit to it here and followup stating 'yeah, I meant Type NM ONLY, not ALL NM cable'.
    But apparently not (apparently did not grasp that stripping the outer sheath from NM-S would create an issue).

    Your section hits the nail ... er ... the single conductors ... on the head - single conductors are to be in a raceway, and a raceway is required to be complete, end to end, enclosure to enclosure, junction box to junction box, before the conductors are pulled in - and that protection sleeve is not a raceway (it is not complete enclosure to enclosure, junction box to junction box, etc).

    Quote Originally Posted by Bill Kriegh View Post
    You don't get to change wiring methods by stripping the sheath off of NM-B cable.

    Wiring methods need to be complete end to end. If the conduit isn't attached to a box on the non-panel end to, it is not a conduit (or tube) wiring method but is just a sleeve, and you can't change wiring methods in a sleeve. This is made pretty clear several places, 300.3 (A) is one


    Jerry Peck
    Construction/Litigation/Code Consultant - Retired
    www.AskCodeMan.com

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    Default Re: Too Many wires in a conduit.

    I missed this part of the discussion somehow, but the NEC makes exceptions to articles, in other articles, all through the book.

    Quote "For an article 300 section to not apply it would have an exception and/or a reference to a section for a specific section which covers the condition were it does not apply. That section would have language such as "Not with standing article 300.16..." If you know of an exception or another section which allows coming out of EMT with cables that do not comply with 300.16 then please refer to it for the sake of all of out educations."

    How about we try 312.5(C) exception

    Which is WHY YOU BUY THE ELECTRONIC VERSION AND SEARCH ALL THE RELATED STUFF or, study your behind off like we did "back when". I'm not going to look it up, but I believe there were drawings of exactly this type of installation in a prior NEC or handbook issue.

    Occam's eraser: The philosophical principle that even the simplest solution is bound to have something wrong with it.

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    Default Re: Too Many wires in a conduit.

    Quote Originally Posted by Bill Kriegh View Post
    How about we try 312.5(C) exception
    These are frequently what stops that exception from be applicable: (bold and underlining are mine)

    312.5 Cabinets, Cutout Boxes, and Meter Socket Enclosures.
    - (C) Cables. Where cable is used, each cable shall be secured to the cabinet, cutout box, or meter enclosure.
    - - Exception: blah, blah, blah provided that all of the following conditions are met:
    - - - (2) The raceway extends directly above the enclosure and does not penetrate a structural ceiling.
    - - - (4) The raceway is sealed or plugged at the outer end end using approved means so as to prevent access to the enclosure through the raceway.

    One of those conditions is this:
    - - - (5) The cable sheath is continuous through the raceway and extends into the enclosure beyond the fitting not less than 6 mm (1/4 in.).

    I said:
    Quote Originally Posted by Jerry Peck View Post
    Ken,

    It is not correct, but first a question - how long is the piece of conduit? That's not shown.

    And I'll make a guess at the length - 8 ft ceiling, top of panel is about 1 ft down, conduit goes through ceiling into attic a sticks up maybe 6 in for a total length of 1-1/2 to 2 ft ... is that about right.
    Ken replied:
    Quote Originally Posted by Ken Amelin View Post
    Not sure how long, but your guess sounds about right. After it enters the basement the wires are exposed
    That tells me that the 'raceway went through the ceiling'. Was it sealed or plugged? Don't know, but I not never found one sealed when I've seen them like that ... unless you count the 'stuffed full of cables' as 'plugging the raceway' ... but based on the photos, one could get maybe one more, two max, cables down through that raceway, so, no, it was not 'plugged', but ... even if it was 'chocked full of cables and no more cables will fit, does that meet this "prevent access to the enclosure through the raceway" - water could leak down through the raceway and into the enclosure, insects could get down through the raceway and into the enclosure, rodents could ... okay, maybe rodents couldn't, but they can get into such small and tiny places where one would think they could not get.

    Jerry Peck
    Construction/Litigation/Code Consultant - Retired
    www.AskCodeMan.com

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