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Thread: wire size

  1. #66
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    Default Re: wire size

    Quote Originally Posted by H.G. Watson, Sr. View Post
    JP: (1) When was this revelation? You were still carring on about this on 8/20/09 continuing to claim that painting was the only effective permanent means! I pointed out to you IN THE NEC (NOT the handbook) where permanent means was defined as taping for identification, using ADHESIVE LABELS, TAGING OR OTHER permanent means.

    See: http://www.inspectionnews.net/home_i...html#post89241


    See: http://www.inspectionnews.net/home_i...html#post97486


    JP: (2) The Handbook is NOT consensus developed, is NOT written by the CMPs it is compiled by the editiors and is NOT to be used to determine the INTENT of the NEC. Try reading the introduction, it specifically warns AGAINST what you are now asserting (regarding the use of the Handbook).

    BK: (3) We don't have to look to the "handbook", we can find it in the CODE itself AND the LISTINGS for the TAPE itself.

    I'm quite tired of these "king of the hill" "last word" and these edicts from the self-proclaimed super duper code inspector/litigation consultant wannabe. You never admit you don't have a leg to stand on, or when you're just plain obviously and outright wrong. Twist warp and be whatever. Those that know, know when you've placed your foot and mouth where the thumb is; most don't BOTHER reading through to see when you totally hang yourself. Sadly those that don't can't tell your head is up your backside or when you're being otherwise creative with a lower orifice.
    PROMISES PROMISES. WHEN WAS YOUR REVELATION THAT "MARKING WITH PAINT OR A MARKER WAS THE ONLY EFFECTIVE PERMANENT MEANS" POSITION WAS WRONG JERRY PECK?

    WHERE WAS IT TO BE NOTICED THAT YOU CHANGED YOUR POSITION?

    Were we to assume this when you didn't take the "last word" on the aforementioned and linked topic string?

    I'm not taking any position on this thread except what I have actually stated. You are NOT invited to interpret what I do or say, frankly you aren't QUALIFIED to do so.

    Inspection Referral SOC

  2. #67
    Marc France's Avatar
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    Default Re: wire size

    JP.,

    I will speak in two langunes here.,

    Je l'observation été celui-ci et me laisse vous dire de mon côté français le code suis de l'exchat le même comme le code de NEC exposé pour remarquer les conducteurs et nous utilisons la bande colorée, perament des marqueurs et d'autres moyens pour rencontrer(respecter) le code.

    Maintenant parlant d'upsizing le conducteur dû la chute de tension nous faisons avec mal fondé et fondé et des conducteurs de base je allready a traité avec cela dû je travaille(marche) sur quelques parking luminaire et la distance peut aller tout à fait un peu {cela non trop commun pour se lever 1 kilomètre ou plus}

    I been watching this one and let me tell you from my French side the code is about the excat the same as the NEC code stated for remarking the conductors and we use color tape , perament markers and other means to meet the code.

    Now speaking about upsizing the conductor due the voltage drop we do with ungrounded and grounded and grounding conductors I allready dealt with that due I work on quite few parking lot luminaire and the distance can go quite a bit { it not too common to get up 1 kilometer or more }

    Merci,Marc


  3. #68
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    Default Re: wire size

    Did we ever get an answer to this question?

    Over the past week or so my curiosity has been peaked with the true identity of HG Watson Sr. He or she does not exist outside of this discussion board, I'm starting to think that HG is the alter ego of a troubled person.

    Phoenix AZ Resale Home, Mobile Home, New Home Warranty Inspections. ASHI Certified Inspector #206929 Arizona Certified Inspector # 38440
    www.inspectaz.com

  4. #69
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    Default Re: wire size

    Check a profile.

    Try PM.

    Try ASKING.
    SP learned a long time ago with his EW wannabe status. P.E. Ph.D. trumps a nobody.

    DH = ?? and head in ...????

    Sponsor has a nice graphic, shows up on every page (Head in...)

    http://www.costofbusiness.com/


  5. #70
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    Default Re: wire size

    Quote Originally Posted by Marc France View Post
    Now speaking about upsizing the conductor due the voltage drop

    Marc,

    Yes, that would be "upsizing", but that is not what is being discussed.

    I don't know French, but I did post it clearly in English for those who read and understand English, do you?

    Your post makes me wonder whether or not you understood English as written in my posts.

    Regarding the NEC and re-identifying conductors ... re-identifying a black, red, or other ungrounded conductor color to white for grounded conductor has been allowed to not be "permanent", it was the reverse, re-identifying a white conductor for ungrounded conductor use which required "permanent" re-identification, and specified "by painting" "or other effective means", and even the tape manufacturers stated that tape was not "permanent", however ... the code changes likely to go into effect in the 2011 NEC changes re-identifying white conductors to an ungrounded conductor use color to specifically include "tape", and thus, what that was found out to be virtually a "done deal", then my argument for insisting that "permanent" meant, as the code wording said "painting" has dropped by the wayside because the code will (in the 2011 NEC) accept non-permanent tape re-identification of white conductors.

    Currently, though, the requirement and wording STILL specifically specify and state "permanent" and "by painting", although that is on its way out, so I have accepted that.

    It seems, however, that Bill and H.G., seem to not have grasped that I have accepted that change here in 2009 when that change WILL NOT BE EFFECTIVE UNTIL 2011. While NOT BEING EFFECTIVE UNTIL 2011, that is the way the code is going, looser with a less stringent requirement, by it own wording change, so if taping *will be* (it is not yet) considered "safe enough" in 2011, then it must therefore be "safe enough" now, even though no allowed by the 2008 NEC. It is simply acknowledging that if it is going to be considered "safe enough" in 2011, then it must be "safe enough" now.

    Which is no different than when we inspect older homes where codes have changed and things done "back then" have been deemed "not safe enough" and changed, and thus were not "safe enough" back then, only no on knew it, but we do today, so we address it today and advise our clients of that knowledge today.

    "Safety" does not know "time" nor does it read code books to know what is allowed when, if something is no longer considered "safe enough" now, then we can be assured that an OLD INSTALLATION is even less than "safe enough".

    Being as it works both ways, determining that something WILL BE CONSIDERED "safe enough" in 2 years is a good indication that it is considered "safe enough" now.

    I know I've just stated the same thing in a couple of different ways, but there are a few people here who seem to have a problem with English, so I figured I would try a few different wordings to see if it helps them understand what is being written. Seems that some PhD/PE people have difficulty reading and understanding English ... and it seems that some PhD people think that PhD means something other than Piled Higher and Deeper and that by that Piled Higher and Deeper PhD they are therefore smarter, even though they come across is being less than smart.

    Jerry Peck, Construction / Litigation Consultant
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  6. #71
    Marc France's Avatar
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    Default Re: wire size

    Quote Originally Posted by Jerry Peck View Post
    Marc,

    Yes, that would be "upsizing", but that is not what is being discussed.

    I don't know French, but I did post it clearly in English for those who read and understand English, do you?

    Your post makes me wonder whether or not you understood English as written in my posts.
    Je comprends vraiment ce que vous dites ici et je suis assez bon avec l'anglais et très bien parlé en français

    I do understand what you are saying here and I am pretty good with engish and very well spoken in French



    Regarding the NEC and re-identifying conductors ... re-identifying a black, red, or other ungrounded conductor color to white for grounded conductor has been allowed to not be "permanent", it was the reverse, re-identifying a white conductor for ungrounded conductor use which required "permanent" re-identification, and specified "by painting" "or other effective means", and even the tape manufacturers stated that tape was not "permanent", however ... the code changes likely to go into effect in the 2011 NEC changes re-identifying white conductors to an ungrounded conductor use color to specifically include "tape", and thus, what that was found out to be virtually a "done deal", then my argument for insisting that "permanent" meant, as the code wording said "painting" has dropped by the wayside because the code will (in the 2011 NEC) accept non-permanent tape re-identification of white conductors.

    Currently, though, the requirement and wording STILL specifically specify and state "permanent" and "by painting", although that is on its way out, so I have accepted that.
    Ok je peux voir votre point de vue cependant si vous êtes conscients combien d'états adopteront le nouveau code tout de suite ? ? IMO non très vite et belive moi les états ont quelques changements le long de la voie. Le plus commencera à l'adopter après 2012 pas avant que l'histoire ne répète comme 2008 NEC le cycle de code.


    Ok I can see your point of view however if you are aware how many states will adopt the new code right away ?? IMO not very fast and belive me the states have some changes along the way. most will start adopting it after 2012 not before the history will repeat just like 2008 NEC code cycle.


    I know I've just stated the same thing in a couple of different ways, but there are a few people here who seem to have a problem with English, so I figured I would try a few different wordings to see if it helps them understand what is being written. Seems that some PhD/PE people have difficulty reading and understanding English ... and it seems that some PhD people think that PhD means something other than Piled Higher and Deeper and that by that Piled Higher and Deeper PhD they are therefore smarter, even though they come across is being less than smart.
    Je laisserai cette partie ouverte et laisserai d'autres membres répondre ici à celui-ci.

    I will leave this part open and let other members here reply this one.

    Merci,Marc


  7. #72
    Cobra Cook's Avatar
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    Wink Re: wire size

    Danelle I hope all of the bull-s--t that has been posted with your question about a 12 wire on a 15 amp circuit has not con"fused" you too much. It is a good question and it is ok to do that, it will not hurt any thing and in most cases it will not help any thing. Just remember that it is still a 15 amp circuit so do not start replacing your 15 amp receptacles with 20 amp receptacles. Most house hold wiring is done in 12 now anyway for the receptacle circuits and the lighting is in 14 but not in all cases. most good electrical contractors just use 12 for both. The problem that could exist in your place is, was part of the circuit in 14? If so just make sure to keep the breaker or fuse at 15 amps only.


  8. #73
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    Default Re: wire size

    Quote Originally Posted by Marc France View Post
    Ok I can see your point of view however if you are aware how many states will adopt the new code right away ?? IMO not very fast and belive me the states have some changes along the way. most will start adopting it after 2012 not before the history will repeat just like 2008 NEC code cycle.
    Marc,

    I understand what you are saying, but my point is that if the nationally respected association which produces the National Electrical Code reduces a standard to a lower level after determining that the lower level is 'safe enough', then it was inherently 'safe enough' from day one (because 'safety' does not read the code, nor even care what it says). If all those people who are a lot smarter than me say 'Hey, we didn't REALLY MEAN "permanent" when we said "permanent", we were just kidding, non-permanent tape really is okay, really.' ... then I am listening to them.

    Jerry Peck, Construction / Litigation Consultant
    Construction Litigation Consultants, LLC ( www.ConstructionLitigationConsultants.com )
    www.AskCodeMan.com

  9. #74
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    Default Re: wire size

    Quote Originally Posted by Jim Port View Post
    After reading that view it still seems clear, as others have said, that the EGC would need to be upsized to correlate with the increased size of the ungrounded conductors.

    The only point of ambiguity that I could see was if a larger conductor size were run and it was not for voltage drop issues, but as a matter of using what was on hand. Since this would not fit either the condition of for proper circuit operation, nor for VD, I could see how someone could take the stance that there is no need to upsize the EGC in this instance. I believe it was Ken that takes the opposing opinion.
    I would like to change my view about the ambiguity of the need to upsize the grounding conductor. According to 250.122(B) this is no condition based on voltage drop or for the practical operation of the circuit. It is very clear to me that I should have read Rollies post #9 more closely.

    Quote Originally Posted by Rollie Meyers View Post
    Here is something from the 2008 NEC section 250.122(B)

    "(B) Increased in Size. Where ungrounded conductors are
    increased in size, equipment grounding conductors, where
    installed, shall be increased in size proportionately according
    to the circular mil area of the ungrounded conductors."

    This is unchanged from the 2002 & 2005 editions.

    This is a big issue when over sizing conductors, & in some cases would disallow the use of NM & UF cables.
    Instead of being swayed by this.

    Quote Originally Posted by Jerry Peck View Post
    And the INTENT of the NEC on this issue is as the Handbook states:
    From the 2008 NEC Handbook:
    - Equipment grounding conductors on the load side of the service disconnecting means and overcurrent devices are sized based on the size of the feeder or branch-circuit overcurrent devices ahead of them. Where the ungrounded circuit conductors are increased in size to compensate for voltage drop or for any other reason related to proper circuit operation, the equipment grounding conductor must be increased proportionately.

    Bill, Ken, and sometimes Rollie,

    Say what you want to, but the Handbook is used to find the INTENT of the NEC by knowledgeable inspectors and experts, heck, WHEN CONVENIENT FOR YOU ... you guys have also tried to use the Handbook to make the code support you ... and now you are trying to degrade the Handbook because IT DOES NOT support your opinion.
    Seems to me the Handbook authors did not read the actual wording of what the Code requires and instead applied artifical conditions that cannot be supported by the Code. Looks like INTENT took us in the wrong direction.


  10. #75
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    Default Re: wire size

    I can't believe it, over 24 hours and no replies.

    Do I get a prize for getting in the last word? What was the previous record?


  11. #76
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    Default Re: wire size

    word


  12. #77
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    Default Re: wire size

    I'm still waiting on a full reply from NFPA.

    So far I have received this: "I have forwarded your question to our electrical code liaison."

    Before replying to the musings of others, I will wait to reply with the reply from NFPA.

    Jerry Peck, Construction / Litigation Consultant
    Construction Litigation Consultants, LLC ( www.ConstructionLitigationConsultants.com )
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  13. #78
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    Default Re: wire size

    The following is why I expect no formal NFPA response to Jerry's request. This is a partial copy of the NFPA comittee rules governing interpretations. Please note 6.1.2 and 6.1.4 (C)

    Note that the following is © NFPA and is used for informational purposes only

    Responses to requests for interpretation are provided by NFPA staff on an informal basis. This allows a timely response that in almost all cases adequately addresses the need for information. A request for an interpretation may, however, be processed on a more formal basis if so desired. This involves balloting the responsible NFPA technical committee, and requires an extended processing time and may not result in an answer if consensus cannot be established. This is referred to as a "Formal Interpretation", and it is used in only limited cases. Refer to Section 6 of the NFPA Regulations Governing Committee Projects.


    Section 6 Formal Interpretations.
    6.1 General. Formal Interpretations are for the purpose of providing
    formal explanations of the meaning or intent of the TC on
    any specific provision or provisions of any Document.
    6.1.1 Limitations. A statement, written or oral, that is not processed
    in accordance with Section 6 of these Regulations shall
    not be considered the official position of NFPA or any of its TCs
    and shall not be considered to be, nor be relied upon as, a Formal
    Interpretation.
    NOTE: This Formal Interpretation procedure does not prevent
    any Chair, Member, or the Staff Liaison from expressing
    a personal opinion on the meaning or intent of the TC on any
    provision of any such Document, provided that: (a) the person
    rendering the opinion orally or in writing clearly states that the
    opinion is personal and does not necessarily represent the position
    of the TC or the Association and may not be considered to
    be or relied upon as such; and (b) written opinions are rendered
    only in response to written requests and a copy of the request and
    the response is sent to the Staff Liaison.
    6.1.2 Nature of Formal Interpretations. Requests for Formal Interpretations
    shall be clearly worded so as to solicit a Yes or No
    answer from the TC and TCC.
    6.1.3 Editions to be Interpreted. Interpretations shall be rendered
    only on the text of the current or immediate prior edition
    of the Document.
    6.1.4 Reasons for Not Processing. A request for an Interpretation
    shall not be processed if it:
    (a) Involves a determination of compliance of a design, installation,
    or product or equivalency of protection
    (b) Involves a review of plans or specifications, or requires
    judgment or knowledge that can only be acquired as a result of
    on-site inspection
    (c) Involves text that clearly and decisively provides the requested
    information

    250.122(B) is one of the most clear and decisive passages in the NEC.


  14. #79
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    Default Re: wire size

    Thank you BK. You said what I was thinking.

    I was mislead by not reading exactly what was written in the Code book articles as posted. I never delved deeper because the Handbook text seemed to agree with what I remembered from a previous edition of the actual code.


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    Default Re: wire size

    Quote Originally Posted by Jerry Peck View Post
    I am delaying responding with additional posts about the "upsizing" issue until I receive a response back from my inquiry to the NFPA about it, which I will post here.

    It will either show:
    1) That I am correct and you ... along with Bill and Ken are wrong, or
    2) That I am wrong and that Bill and Ken are correct.

    Either way, I have asked the question of NFPA and will post their response.

    While I fully expect the response to be the same as the Handbook, I will post the response WHICHEVER WAY IT COME BACK.

    If I am wrong, I am wrong.

    If I am not wrong, then you are (as you seem to have chimed in and sided with Bill and Ken).

    We shall see who is correct and I will post it here for all to see ... like it or not.
    Here is their response - got it today:

    ~~~~~~~~~~~~~~
    From: Cloutier, Mark [mailto:mcloutier@NFPA.org]
    Sent: Tuesday, December 22, 2009 10:19 AM
    To: codeman@AskCodeMan.com
    Cc: jcarpenter@iaei.org; Johnston, Michael; Henderson, Carol
    Subject: RE: NEC 250.122 (Log #29202)MC

    To: Jerry Peck
    Date: 12/22/09

    This is in reply to your email concerning the National Electrical Code®. The NFPA electrical staff cannot approve a particular design or arrangement, comment on workmanship issues, review or perform calculations for compliance. Issues of compliance are the responsibility of the Authority Having Jurisdiction, but I can provide some general remarks.

    Section 250.122(B) requires an equipment grounding conductor (EGC) on the load side of an overcurrent device to be increased in size wherever the associated ungrounded conductors are increased in size. The increase in size of the EGC must be done proportionately according to the circular mil area of the ungrounded conductors. Once the ungrounded conductors are increased in size for whatever reason deemed necessary, 250.122(A) is no longer applicable and the requisite requirements of 250.122(B) are required.

    Mark Cloutier
    NFPA Senior Electrical Engineer

    Important notice! This correspondence is not a Formal Interpretation issued pursuant to NFPA Regulations. Any opinion expressed is the personal opinion of the author, and does not necessarily represent the official position of the NFPA or its Technical Committees. In addition, this correspondence is neither intended, nor should be relied upon, to provide professional consultation or services.
    ~~~~~~~~~~~~~~~~~~~

    The response DOES NOT coincide with the statements in the NEC Handbook, which is what I based my statements on, therefore the Handbook and I are both wrong.

    As I said, like it or not, I will post the answer.

    I posted the answer, you will probably like it.

    Jerry Peck, Construction / Litigation Consultant
    Construction Litigation Consultants, LLC ( www.ConstructionLitigationConsultants.com )
    www.AskCodeMan.com

  16. #81
    Roger Frazee's Avatar
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    Default Re: wire size

    Thought I would reply to see if we can beat mike holts record of 85 posts on this argument of 250.122(b).

    But since I replied I'm sorry but I am having a difficult time understanding why "for any reason".. makes sense....as to the intent of the cmp's language. Are we saying if I need to run a 40 amp feeder and I don't have any # 8 nm on the truck that I would not be able to run # 6 nm because it doesn't have a # 8 egc?? Using Kens calculation method I would need an egc equal to 1.59 x 10380cm = 16504cm = # 8 awg egc.

    I could swear that in earlier codes prior to 2002 the language was "upsized for reasons like voltage drop" if that is correct why the language change / Or / if a language change why would the intent change ?

    The reply from nfpa states "deemed necessary" .. isn't it a stretch to say that means for any reason??

    Why would the intent be to say a # 10 awg doesn't cut it for a 40 amp circuit on #6 unless there is a reason to force the egc to be upsized? Otherwise if I later install a 50 amp breaker for more load capacity on the # 6 I can now have a # 10 egc...?????

    IMO the language is not reflecting the intent and causing confusion. I would like to think that the intent has to be based on some reason to force an egc upsize. If I need a 40 amp circuit and I can't install it on 8 awg because the distance is too great for Vd reasons then if I have to place a fatter wire on the 40 amp breaker to adjust for VD in the ungrounded conductors then I would likewise have to upsize my egc to insure the low impedance for opening the protective device so it would not burn through on fault.

    Am I to think that if I install a 40 amp range branch circuit on 6 awg with 10 awg ground nm-b because I don't have any # 8 on the truck I am in violation of 250.122(B) ? Surely this isn't the intent.....

    MY thinking has always been table 250.122 is for sizing the egc when there aren't any reasons or applications deemed necessary to change the size of the egc.

    250.122(A) says in no case shall the egc be larger than the ungrounded conductors or words to that effect. Isn't that saying that there must be the possibility of reasons that might require upsizing the egc?


  17. #82
    Roger Frazee's Avatar
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    Default Re: wire size

    I dug out my old paper back nec's ... 1999 250.122(b) Adjustment for voltage drop. When conductors are adjusted in size to compensate for voltage drop, equipment grounding conductors, where installed, shall be adjusted proportionately according to circular mil area.

    Ok so there was only one reason to upsize the egc in 1999 so new language is now saying ' for any reason' ?? Why would fatter wire on a 40 amp branch circuit that has no reason or purpose 'deemed necessary' require a larger EGC ...?

    Last edited by Roger Frazee; 12-23-2009 at 09:05 AM. Reason: spellin

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    Default Re: wire size

    JP-
    I received the same exact email from the same exact person yesterday also.
    I ran into technical difficulties when trying to post it yesterday, hence my deleted post.


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    Default Re: wire size

    Quote Originally Posted by Roger Frazee View Post
    IMO the language is not reflecting the intent and causing confusion. I would like to think that the intent has to be based on some reason to force an egc upsize.

    Roger,

    I agree, and so does the Handbook, but ... the code and the response do not agree.

    Jerry Peck, Construction / Litigation Consultant
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    Default Re: wire size

    Quote Originally Posted by ken horak View Post
    JP-
    I received the same exact email from the same exact person yesterday also.
    I ran into technical difficulties when trying to post it yesterday, hence my deleted post.

    Ken,

    I disagree with that response, as does the Handbook, but ... the response does repeat what the code itself says, so ...

    ... I've got to go with that response.

    When I posted it, I had to remove all that extra font garbage which gets put in there, is that what happened when you tried to post it?

    Jerry Peck, Construction / Litigation Consultant
    Construction Litigation Consultants, LLC ( www.ConstructionLitigationConsultants.com )
    www.AskCodeMan.com

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    Default Re: wire size

    JP-
    Yep that was one issue, the other was my laptop was doing some screwy things at the time. I was going to repost it from home with the desktop,but didn't get a chance prior to your posting it.


  22. #87
    Kevin Kayden's Avatar
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    Default Re: wire size

    Hello;

    As a first post here, hopefully people will be understanding about reigniting the big debate over a probably unheard of technical point (I tried to search), but I did have one more question regarding the Equipment Grounding Conductor.

    According to NEC 250.122(A), it states, "equipment grounding conductors ... but in no case shall be required to be larger than the circuit conductors supplying the equipment." Does that mean that since the EGC is not "required" to be larger than the circuit conductor, it could be if somebody decided to do it anyway? As a ridiculous example, say a 2AWG EGC for a 15 amp circuit.

    Further, according to 250.122(B), it states, "shall be increased in size proportionately according to the circular mil area of the ungrounded conductors." Since only 250.122(B) would now be considered with oversized current carrying conductors, does that mean that the EGC MUST be oversized in only that ratio, and could not be larger than the circuit conductor under any circumstances? And thus, for that 15 amp circuit, it could not be larger than the circuit conductor, since it must be "proportionately?"


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    Default Re: wire size

    Keep in mind the NEC is the Minimum requirement allowed.
    Thus oversizing your Grounding conductor is not a problem at all. The issue comes when one decides to increase in size the ungrounded conductors ( for what ever reason).


    The use of the word Proportionately is the code making panels way of saying increase the size of the grounding conductor by the same proportion you increased the ungrounded conductor.This is the minimum requirement. If you chose to use a larger grounded conductor thats no big deal.
    The code is telling you that you do not need to have a larger grounded conductor then the ungrounded conductor, but it can be if you so desire.


  24. #89
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    Default Re: wire size

    Quote Originally Posted by ken horak View Post
    Keep in mind the NEC is the Minimum requirement allowed.
    Yes, sometimes when you're following their rules I forget that. Thanks for the help.


  25. #90
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    Default Re: wire size

    There have been many good responses why using a larger cable is not a good idea, even though it is not an inherent safety risk. The lower voltage drop occurs because larger a larger diameter wire has less resistance than a smaller wire.

    On a pedantic note, a larger diameter wire has a larger capacitance than a smaller one. If used in AC applications, the larger wire will incur a power loss from the AC generator needing to drive the increased capacitance. For typical AC installations, the power savings from the lower impedance will be much greater than the loss from driving the increased capacitance; hence larger diameter wires can save power (and therefore money). However, for very long AC runs, the loss due to capacitance can be significant. This is why many long-distance power transmission systems (e.g., underwater power cables) now use HVDC (High Voltage Direct Current).

    On the other hand, if the cable is intended for DC applications, capacitance is a non-issue and larger diameter wires can be very desirable. For example, when designing a low voltage DC outdoor lighting network, wire length is severely limited because of voltage drop. Larger diameter wires can extend the effective wire length from the transformer.

    Last edited by Robert L. Ayers; 01-25-2010 at 02:35 PM.

  26. #91
    Join Date
    Oct 2009
    Location
    michigan
    Posts
    421

    Default Re: wire size

    All well said in this thread.
    Whenever, as an electrician, I installed larger conductors for such as but not limited to: Volt-drop, #of conductors in a raceway, etc,
    I would tag the conductor in the panel stating '20 amp max' for example.
    I wish this would become a code requirement....what U fellas think of that idea?
    Bob Smit, County Electrical Inspector


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