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  1. #1
    mathew stouffer's Avatar
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    Default Power for AC condensers

    150 amp service and the AC condensers were installed in 03. There are fuses in the disconnect. The feeders have been tapped then spliced. Could not find specific literature in the IRC. Jerry any thoughts No tape this time.

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  2. #2
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    Default Re: Power for AC condensers

    That can't be right. Those are spliced into SEC and should be fed to main service panel with circuit breaker protection as well as fused disconnect.


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    Default Re: Power for AC condensers

    Quote Originally Posted by mathew stouffer View Post
    150 amp service and the AC condensers were installed in 03. There are fuses in the disconnect. The feeders have been tapped then spliced. Could not find specific literature in the IRC. Jerry any thoughts No tape this time.

    Are those taps on "feeders" to a load-side panel, or on the "service entrance conductors" from the meter to the service equipment?

    If those are "feeders", is there a disconnect at the service equipment?

    In any case, are those taps listed for these conductor materials/types/AWGs.. (not a rhetorical question, I don't know).

    Last edited by Michael Thomas; 07-28-2010 at 08:07 AM.
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    Default Re: Power for AC condensers

    Well, since someone has to relocate the disconnects to allow for proper clearance, they can go ahead and re-wire the setup at the same time.


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    Default Re: Power for AC condensers

    Experience talking here. Never leave a good pair of sunglasses on top of a condensing unit.

    rick


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    Default Re: Power for AC condensers

    Those taps ,are they 10' or less? Lets look at the 2008 NEC
    Article 240.21(B)(1)

    B) Feeder Taps. Conductors shall be permitted to be tapped, without overcurrent protection at the tap, to a feeder as specified in 240.21(B)(1) through (B)(5). The provisions of 240.4(B) shall not be permitted for tap conductors.

    240.21(b)(1)>(1) Taps Not over 3 m (10 ft) Long. Where the length of the tap conductors does not exceed 3 m (10 ft) and the tap conductors comply with all of the following:

    (1) The ampacity of the tap conductors is

    a. Not less than the combined calculated loads on the circuits supplied by the tap conductors, and

    b. Not less than the rating of the device supplied by the tap conductors or not less than the rating of the overcurrent protective device at the termination of the tap conductors.

    (2) The tap conductors do not extend beyond the switchboard, panelboard, disconnecting means, or control devices they supply.

    (3) Except at the point of connection to the feeder, the tap conductors are enclosed in a raceway, which shall extend from the tap to the enclosure of an enclosed switchboard, panelboard, or control devices, or to the back of an open switchboard.

    (4) For field installations where the tap conductors leave the enclosure or vault in which the tap is made, the rating of the overcurrent device on the line side of the tap conductors shall not exceed 10 times the ampacity of the tap conductor.


    If they are longer then 10' Lets also look at the 2008 NEC
    Article 240.21(B)(2)


    2) Taps Not over 7.5 m (25 ft) Long. Where the length of the tap conductors does not exceed 7.5 m (25 ft) and the tap conductors comply with all the following:
    (1) The ampacity of the tap conductors is not less than one-third of the rating of the overcurrent device protecting the feeder conductors.

    (2) The tap conductors terminate in a single circuit breaker or a single set of fuses that limit the load to the ampacity of the tap conductors. This device shall be permitted to supply any number of additional overcurrent devices on its load side.

    (3) The tap conductors


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    Default Re: Power for AC condensers

    Quote Originally Posted by Rick Hurst View Post
    Experience talking here. Never leave a good pair of sunglasses on top of a condensing unit.

    rick
    How many scrolled back up and opened the picture after reading this?

    Not me!!!!!!!!!


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    Default Re: Power for AC condensers

    Quote Originally Posted by mathew stouffer View Post
    Jerry any thoughts

    Mat,

    Where to start ...

    Being as the taps appear to be FEEDER taps, Ken Horak addressed that part with the two sections which would be applicable depending on the tap conductor length.

    When measuring the conductor length do not just measure the liquidtight, actually measure *the conductor length*, which means the bent, twisted, and curled part adds length to the conductor length.

    Dom addressed the lack of required working space in front of the disconnects - the condenser units would need to be at least 30" apart, including the mounting pads they are on ...

    Which brings us to the mounting pads being cantilevered off the concrete pad and over/on the stone, making those pads not installed as stable as they should be.

    Rick addressed the damaging the fan blade aspect when the sunglasses ear piece slips down between the louvers ...

    Of course, even though Ken addressed the requirements for the taps, what has been opened in that can of worms (to some it is a can of worm as they do not understand what the code specifically states) is related to the location of those taps, specifically: 312.8 in the NEC: (underlining, bold and red are mine)
    - 312.8 Enclosures for Switches or Overcurrent Devices.
    - - Enclosures for switches or overcurrent devices shall not be used as junction boxes, auxiliary gutters, or raceways for conductors feeding through or tapping off to other switches or overcurrent devices, unless adequate space for this purpose is provided. The conductors shall not fill the wiring space at any cross section to more than 40 percent of the cross-sectional area of the space, and the conductors, splices, and taps shall not fill the wiring space at any cross section to more than 75 percent of the cross-sectional area of that space.

    We have been over the above section many times and there is no listing standard to which a panelboard/enclosure can be listed which provides space for that purpose.

    That means the tap ARE allowed, within the requirements Ken posted, however, the taps are just not allowed IN THERE with the overcurrent device (the main disconnect). The taps WOULD BE allowed in a wire gutter under that enclosure, i.e., the feeders could go down into a wire gutter, be tapped as shown, then run out of the wire gutter (but not back up into the main disconnect enclosure) and to the panel the feeders are supplying. Of course, though, lack of planning originally for this future addition does not make it easy to meet code when tapping off for the a/c units, but "not making it easy" is no excuse to not meet code.

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    Default Re: Power for AC condensers

    Unless the manufacturers were all seeing and all knowing how would someone expect them to be able to designate a specific area inside an enclosure just for splices and taps? Change the size of the feeders and you would change the amount of area still available for other splices. Designate the area on the right, oopps maybe the left. Darn I can't use an equivilant area at the bottom? There are too many variables to be accounted for to expect an area to be labeled "for this purpose".

    What if you were to use some of that space inadvertantly when the conductor was formed into the lug. Clearly this would be a listing and labeling issue and the equipment is no longer fit for its listed use. My gosh, the hazards that could be encountered.

    I am glad that most people can see the folly by what some propose.


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    Default Re: Power for AC condensers

    Quote Originally Posted by Jim Port View Post
    Unless the manufacturers were all seeing and all knowing how would someone expect them to be able to designate a specific area inside an enclosure just for splices and taps? Change the size of the feeders and you would change the amount of area still available for other splices. Designate the area on the right, oopps maybe the left. Darn I can't use an equivilant area at the bottom? There are too many variables to be accounted for to expect an area to be labeled "for this purpose".
    Okay, so, when you install on of those combination meter/service equipment enclosures which have the dedicated area on the left for the service entrance conductors to pass through behind the grounded metal barrier ... you choose to run the service entrance conductors up the right side?

    Are you kidding me?

    There is no space provided for that purpose because what is of concern is HOW MUCH CURRENT, HOW MANY OF WHAT SIZE CONDUCTORS, would be allowed to run through the vertical section of the panel. A manufacturer COULD say that they want to allow 200 amps maximum to run through (across the bottom of) the vertical panel section, and then install a grounded barrier (not unlike you find in the combination meter/service equipment enclosures I referenced above) and have them tested for heat rise and all the other things they are tested for. The manufacturer would need to work with UL in coming up with a standard for what they want, the panels would be tested at the maximums requested by the manufacturer, and, if those panels passed the tests (and they very well might - but no manufacturer has asked or tried) then THOSE panels would be approved for that use as space would be provided for that purpose.

    You want to run the conductors vertically up one side? Then the manufacturer would have had to include that in the standard, that would have had to have been tested, and then, sure, up to the maximum allowed by the standard and the now tested and listed labeling.

    Until then, and no manufacturer as yet requested otherwise, the code states, really quite simply, "Enclosures for switches or overcurrent devices shall not be used as junction boxes, auxiliary gutters, or raceways for conductors feeding through or tapping off to other switches or overcurrent devices, ... " and then adds " unless adequate space for this purpose is provided." for when, IF, a manufacturer decides they have a need for such a listing, and at all that expense to create the standard, create the specialized product, and have them tested.

    Until then, though, the code states "Enclosures for switches or overcurrent devices shall not be used as junction boxes, auxiliary gutters, or raceways for conductors feeding through or tapping off to other switches or overcurrent devices,"

    That really is quite simply and quite explicitly stated.

    Not sure why some electricians have trouble reading "SHALL NOT BE USED AS" and then reading the 'what they shall not be used as' part "JUNCTION BOXES, AUXILIARY GUTTERS, or RACEWAYS for ... "

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  11. #11
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    Default Re: Power for AC condensers

    I have to agree with Jim. What the code is saying is don't over-fill an enclosure with to many wires. That is why they give percentage of fill. I have made taps in panel boxes any never had any turned down as long as I made sure "adequate space for this purpose was available"


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    Default Re: Power for AC condensers

    Quote Originally Posted by James Duffin View Post
    What the code is saying is don't over-fill an enclosure with to many wires. That is why they give percentage of fill.
    That part is correct. That is what the second sentence is for - to limit conductor fill.

    as long as I made sure "adequate space for this purpose was available"
    Your "adequate space for this purpose" is for conductor fill.

    YOU cannot make adequate space for junction boxes, auxiliary gutters or raceways, only the manufacturer can, and that would have to be to a standard which does not exist as no manufacturer as deemed it necessary. The NEC quite clearly states "Enclosures for switches or overcurrent devices shall not be used as junction boxes, auxiliary gutters, or raceways for conductors feeding through or tapping off to " - not sure why you are having such a time reading what is clearly stated. I have talked with Senior Engineers at UL about this at length on various occasions over the years, they always go to UL Standard 67, the standard to which enclosures and panelboards are listed to, and it clearly states in there what the code states, and they explain why (like I did above, there would be a LOT of combinations to consider to the manufacturers would need to 'pick a maximum' number/size of conductors and current to be allowed through, etc.), no manufacturer as found a need to do so.

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    Default Re: Power for AC condensers

    The two of you are effectively looking at a STOP sign and thinking it really means 'slow' because you really do not want to come to a full stop, and besides, there are no other cars there, so why should you come to a full stop ...

    Why? Because the sign says STOP for a reason.

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  14. #14
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    Default Re: Power for AC condensers

    I have no problems reading and understanding nor do I have problems performing and getting my work approved. What matters is that an installation is safe and meets the requirements of the customer....oh yeah...an passes an electrical inspection. The real world can not afford ($) the type of tunnel vision that you sometime apply to situations. I will never talk to UL about a problem because I do not have to satisfy them.

    A good example is what is required in the 2009 code for a hot tub bonding grid. If you are installing a hot tub on an existing concrete pad, one county I work in requires you to tear up the concrete pad to install the bonding grid in the new concrete. The county next door allows you to saw-cut the existing concrete and install the #6 bare copper in the saw-cut and cement over it. Both serve the same purpose but one is just plain silly. I'm sure we'll disagree as to which one is silly!


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    Default Re: Power for AC condensers

    Quote Originally Posted by James Duffin View Post
    The real world can not afford ($) the type of tunnel vision that you sometime apply to situations.

    The real world has codes which have requirements for reasons, and that is one of those requirements, and there are reasons for the requirement.

    I am glad you came out of the closet and told us you do not care what the code says, you do it the way James Duffin says - guys like you keep home inspectors in business. We all owe James here a round of applause and we need to encourage him to "keep doing it James' way" as that will keep other local home inspectors in business.

    Fortunately, or is that unfortunately , every area is full of contractors like James above, and that will keep home inspectors in business for generations to come.

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    Default Re: Power for AC condensers

    YOU cannot make adequate space for junction boxes, auxiliary gutters or raceways, only the manufacturer can, and that would have to be to a standard which does not exist as no manufacturer as deemed it necessary
    You cannot make space for the junction boxes? The junction boxes define the space. I am not sure where this is going, but if the space exists I can fill it to the limits imposed. If the enclosure contains 200 cubic inches and I can fill it to 40% of the cross sectional area the fill ratio is the same regardless if i use #12 or 4/0.


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    Default Re: Power for AC condensers

    Lets approach this from the other direction. If no manufacturer feels no need to have the product listed "with adequate space for that purpose" why would the NEC clearly state that splices and taps are allowed. Clearly that would violate the UL listing.

    I am glad that more reasonable heads prevail instead of taking a section out of context by emphasizing the wrong part of the article.


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    Default Re: Power for AC condensers

    I would also like to thank all the ill-informed HI's for writing up defects that have no backing other than "because I think so" or misconstrueing the actual Code requirements. Keep on writing those checks.

    Its also ironic that a profession that does not "do code" relies so heavily upon it to attempt to validate their point of view, often times without the training or understanding of the subject matter.


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    Default Re: Power for AC condensers

    Quote Originally Posted by Jim Port View Post
    You cannot make space for the junction boxes? The junction boxes define the space. I am not sure where this is going, but if the space exists I can fill it to the limits imposed. If the enclosure contains 200 cubic inches and I can fill it to 40% of the cross sectional area the fill ratio is the same regardless if i use #12 or 4/0.
    Yes ... as I HAVE BEEN TELLING YOU ... to the limits allowed FOR THE CONDUCTORS WHICH TERMINATE IN that enclosure.

    NO ... as I HAVE BEEN TELLING YOU ... for conductors which use that as a junction box, raceway or auxiliary gutter and feed through that enclosure.

    You keep trying to mix the two above, and that is your problem.

    NO - *YOU* cannot *MAKE* that space into what *YOU* want it to be, that is defined by the standard to which it is tested, listed, and labeled, and THE MANUFACTURER *MAKES* that space to be whatever the standard is they are listing to, and in this case the NEITHER the standard and nor the code allows *YOU* to make that space for that use, in fact the code specifically states "shall not be used as junction boxes, auxiliary gutters, or raceways for conductors feeding through or tapping off to".

    Not comprehending what it is you do not get about "shall not be used as" and "for conductors feeding through or tapping off to".

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    Default Re: Power for AC condensers

    As I stated back in post #8:

    Quote Originally Posted by Jerry Peck View Post
    We have been over the above section many times ...

    I *KNEW* we would have to go through this all over again for a few who still refuse to "get it".

    It really is as simple as reading at first grade level: SHALL NOT BE USED FOR ... the longest words in there is only 4 letters ... those are not real big words, those words should be real easy to understand.

    I can somewhat understand you not understanding this part: for conductors feeding through or tapping off to ... it has some bigger words in it ... "conductors" ... "feeding" ... "through" ... those probably are above first grade level.

    Jeez, guys, r-e-a-d s-l-o-w-l-y if you need to:

    SHALL

    NOT

    BE

    USED

    AS

    ... then it uses some bigger words to state what it shall not be used as ...

    ... then it states the tricky part ...

    "for conductors feeding through or tapping off to"

    That means that conductors terminating IN the enclosure are okay, to the fill percentage, just like we all have said.

    That specifically states NOT for use for conductors "feeding through or tapping off to".

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    Default Re: Power for AC condensers

    Quote Originally Posted by Jim Port View Post
    Lets approach this from the other direction. If no manufacturer feels no need to have the product listed "with adequate space for that purpose" why would the NEC clearly state that splices and taps are allowed. Clearly that would violate the UL listing.

    For the same reason that the NEC specifies that not more than one neutral is allowed in one terminal ... even though the manufacturers DID NOT ADDRESS THIS FOR DECADES as not being allowed, it was not allowed because they did not specify it as being allowed.

    That space is not for the purpose of conductors feeding through, it is not allowed, the manufacturers do not allow for it, the NEC specifically states SHALL NOT BE USED FOR ... at some point the manufacturers may eventually say "Golly, I guess we need to specify NOT TO DO THAT in addition to the code saying NOT TO DO THAT because there are enough people who do not understand plain English."

    Yes, maybe it will come to that some day. It did for the one neutral conductor per terminal, but it took decades to state that.

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    Default Re: Power for AC condensers

    It would certainly have been more clear for the CMP just to say "No splices shall be allowed" if that is what they really meant. Instead they specify a percentage of fill for something that is not allowed? Why all the effort for no benefit?

    unless adequate space for this purpose is provided. The conductors shall not fill the wiring space at any cross section to more than 40 percent of the cross-sectional area of the space, and the conductors, splices, and taps shall not fill the wiring space at any cross section to more than 75 percent of the cross-sectional area of that space.

    Last edited by Jim Port; 07-29-2010 at 06:57 AM.

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    Default Re: Power for AC condensers

    I suppose it goes without saying that the deterioration and corrosion of the exterior of the combo meter/disconect enclosure needs to be addressed.

    I also take "issue" with the grounding lug/terminal being used for multiple conductors, question the emt strength & diameter for GEC protection, and size/type of equipment bond at the right.

    P.S. speaking of bad habits/practices (sun glasses, etc.), leaning the conductive, sharp edged applaince access panel cover against the unit and in contact with earth also bad and unsafe practice, for several reasons, not the least of which is should it slip, it can damage the enamel paint on the guard, damage the fins, make contact with you, etc. Other, more serious consequences could occur. When remove, suggest place in a more appropriate position, for personal protection safety, as well as avoidance of equipment damage.

    Last edited by H.G. Watson, Sr.; 07-29-2010 at 09:13 AM.

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    Default Re: Power for AC condensers

    Quote Originally Posted by H.G. Watson, Sr. View Post
    I suppose it goes without saying that the deterioration and corrosion of the exterior of the combo meter/disconect enclosure needs to be addressed.

    I also take "issue" with the grounding lug/terminal being used for multiple conductors, question the emt strength & diameter for GEC protection, and size/type of equipment bond at the right.
    That is typical of Zinsco/Sylvania/Challenger resi 3R panels & that main is a Zinsco design......

    The nicest thing I can say about the whole thing is it is less then a "professional" installation, the sealtite to those "Lemonix*" condensing units looks like a A/C service tech job...

    *Off topic but Trane/American Standard residential, & Lennox equipment sucks. (As it was said many years ago, "there is a sucker born every minute").


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    Default Re: Power for AC condensers

    Quote Originally Posted by Jim Port View Post
    Instead they specify a percentage of fill for something that is not allowed?

    The conductors shall not fill the wiring space at any cross section to more than 40 percent of the cross-sectional area of the space, and the conductors, splices, and taps shall not fill the wiring space at any cross section to more than 75 percent of the cross-sectional area of that space.
    Again, you are missing the basic words, I will repeat them to help you and others (if needed for others):
    "for conductors feeding through or tapping off to other switches or overcurrent devices"

    WHEN (that is the reason it is in there) ... WHEN ... such as the correcting of multiple tapped breakers ... WHEN you SPLICE (that is what you are doing) the two or more conductors from the multiple tap to another conductors which then goes to the breaker - THAT IS allowed as the conductors do not feed through or tap off to "other switches or overcurrent devices".

    That code section really is quite simply stated and quite simply means what it says, all you have to do is read the words and understand what the words say.

    As soon as you try to expound on trying to make it apply to something it does not, you are outside the wording of that section, which is really quite simply written.

    The difference from correcting the multiple tap and the taps to those a/c condenser units is that those taps - if installed according to the tap rules - feed the OVERCURRENT DEVICE, and that is strictly prohibited by that wording

    Again, it is all in the simple wording of what it says.

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  26. #26
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    Default Re: Power for AC condensers

    This nonsense is why a HI is required to refer this type of problem to a licensed electrical contractor. A fanatical HI can cost someone a pile of money just trying to prove a point.


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    Default Re: Power for AC condensers

    Quote Originally Posted by James Duffin View Post
    This nonsense is why a HI is required to refer this type of problem to a licensed electrical contractor. A fanatical HI can cost someone a pile of money just trying to prove a point.
    How true, and you being fanatical about trying to prove your point that what is in the code does not matter can really cost someone a pile of money when things go wrong.

    I really never can understand why some people will spend so much time trying to defend doing it wrong when the code is so clearly worded on what "shall not" be done.

    Keep on keeping on showing us how much time and effort you put into trying to defend your defenseless position.

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    Default Re: Power for AC condensers

    Quote Originally Posted by Jim Port View Post
    I would also like to thank all the ill-informed HI's for writing up defects that have no backing other than "because I think so" or misconstrueing the actual Code requirements. Keep on writing those checks.

    Its also ironic that a profession that does not "do code" relies so heavily upon it to attempt to validate their point of view, often times without the training or understanding of the subject matter.



    I also find it ironic that some guys use the code to try and validate their point of view, but fail to use the correct code! If one is using the code to validate their points, one should first determine which code is the adopted code for the area they are in. I see alot of HI automatically start quoting the electrical section of the IRC, when most places in the United States have adopted the NEC for the electrical code.


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    Default Re: Power for AC condensers

    Quote Originally Posted by Jerry Peck View Post
    312.8 in the NEC: (underlining, bold and red are mine)
    - 312.8 Enclosures for Switches or Overcurrent Devices.
    - - Enclosures for switches or overcurrent devices shall not be used as junction boxes, auxiliary gutters, or raceways for conductors feeding through or tapping off to other switches or overcurrent devices, unless adequate space for this purpose is provided. The conductors shall not fill the wiring space at any cross section to more than 40 percent of the cross-sectional area of the space, and the conductors, splices, and taps shall not fill the wiring space at any cross section to more than 75 percent of the cross-sectional area of that space.
    .
    If the passage said "Enclosures for switches or overcurrent devices shall not be used as junction boxes, auxiliary gutters, or raceways for conductors feeding through or tapping off to other switches or overcurrent devices. period. I could see your point, however there is a comma, which continues the thought. The unless modifies the entire passage that precedes it and sets the condition that you cannot have reached the maximum conductor fill in order to add a tap or a splice. The next sentence imposes the limits of fill.


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    Default Re: Power for AC condensers

    Quote Originally Posted by Jim Port View Post
    If the passage said "Enclosures for switches or overcurrent devices shall not be used as junction boxes, auxiliary gutters, or raceways for conductors feeding through or tapping off to other switches or overcurrent devices. period. I could see your point, however there is a comma, which continues the thought.
    Jim continues with:
    The unless modifies the entire passage that precedes it and sets the condition that ...
    That part is also correct. The "unless" modifies the entire passage based on "unless adequate space for this purpose is provided." and that is key, and the key part of that is "space for that purpose" and "space for that purpose" ... i.e., space for feeding through or tapping off to other overcurrent devices ... is not provided.

    ... you cannot have reached the maximum conductor fill in order to add a tap or a splice. The next sentence imposes the limits of fill.

    Almost correct. The limits of the fill are not for the taps or splices alone:
    The conductors shall not fill the wiring space at any cross section to more than 40 percent of the cross-sectional area of the space, and the conductors, splices, and taps shall not fill the wiring space at any cross section to more than 75 percent of the cross-sectional area of that space.
    The limits of fill are for: a) "The conductors shall not fill the wiring space at any cross section to more than 40 percent of the cross-sectional area of the space,"; and b) "and the conductors, splices, and taps shall not fill the wiring space at any cross section to more than 75 percent of the cross-sectional area of that space." where only b) addresses the taps AND splices AND the conductors.

    The first part, a), addresses only the conductors and allowed up to 40 percent fill.

    The second part, b) allows another 35 percent for the taps and splices where the taps and splices meet the allowable taps and splices, which add c) taps and splices which DO NOT feed through or go to other overcurrent devices and are allowed regardless; and d) taps and splices which DO feed through or go to other overcurrent devices and are allowed ONLY IF "space for that purpose is provided", and space for THAT PURPOSE is not provided.

    I've tried every way I can to explain the math:
    that: 1+1+1+1+1+1=6
    and that: 2+2+2=6
    and that:3+3=6
    and that 2+4=6
    and that 1+2+3=6
    even that 2x3=6

    I can sense that you are almost there, but I do not know very many other ways to explain that 1+1+2+2=6.

    No matter how much some want that to equal 5 or 7 ... it simply does not.

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

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    Default Re: Power for AC condensers

    The second part, b) allows another 35 percent for the taps and splices where the taps and splices meet the allowable taps and splices, which add c) taps and splices which DO NOT feed through or go to other overcurrent devices and are allowed regardless; and d) taps and splices which DO feed through or go to other overcurrent devices and are allowed ONLY IF "space for that purpose is provided", and space for THAT PURPOSE is not provided.
    So you expect someone to believe that taps going to overcurrent devices can only use the enclosure if "space is provided" but a splice or tap that does not leave that same enclosure can fill the same enclosure another 35%? Explain the logic in that, other than the fact that if you stop reading too soon it changes the context.


  32. #32
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    Default Re: Power for AC condensers

    That's not the SEC that's being tapped, it is the main power feeder.

    You three are arguing inopposite the NFPA Style manual, and misreading the article(s) which apply.


  33. #33
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    Default Re: Power for AC condensers

    That is correct, it is the main feeders. 150 amp service disconnect feeding the distribution panel on the interior of the home.


  34. #34
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    Default Re: Power for AC condensers

    I'm going to weigh in on Jim's & Jame's side.

    This nonsense is why a HI is required to refer this type of problem to a licensed electrical contractor. A fanatical HI can cost someone a pile of money just trying to prove a point. - gotta admit...I agree with this.

    BTW - neither 240.21(B)(1) or (2) apply in this case...(B)(5) applies 'outside taps' can be unlimited in length.

    This argument that taps can't be in the panel because the mfr. didn't design his panel for such and getting into the minutia of this & that word is lawyer speak for 'let's see if I can confuse the jury enough to screw someone over'.

    I belong to a prof. organization that meets with UL monthly and this discussion was taken up recently...this has nothing to do with a mfr. 'designing' space for such taps, it is whether or not the panelboard has the space for such taps...simple yes or no.

    The panel in question has plenty of space in it for such a splice.

    RE: 110.26(A)(2) - proper working space between the condensers at the disconnet...you could argue this is a valid point - however - since the disconnect [read breaker] for the feeder [where the tap was taken] is within sight of the condensors you could just as easily turn off the breaker to the feeder and thus deenergize the tap conductors...inconvenient for all the devices being turned off with the main feeder - sure, but we're talking code compliant, not convenience.

    RE:
    Which brings us to the mounting pads being cantilevered off the concrete pad and over/on the stone, making those pads not installed as stable as they should be....
    whew! isn't that a stretch and 3/4!! 1/2 the pad is on the concrete and the other 1/2 of the pad is on a crushed rock base...and somehow this installation makes these pads 'not installed as stable as they should be.?? I like that should be part. I should be the winner of an interstate lottery and retire in luxury. Could there be a base constructed differently...sure...but should there be? Why, this base is obviously doing its job just fine...which brings us back to that snide remark about fanatical HIs.

    I'm a certified electrical inspector working for a municipality. The difference between my job and HIs is that I'm required to inspect to the code while HIs get to be fanatical and cost home owner's lots of money.

    RE: "I also take "issue" with the grounding lug/terminal being used for multiple conductors" - GOOD CATCH! No one caught that item 'cept you. That actually is a valid call as those lugs are UL listed for one conductor.

    RE: "I question the emt strength & diameter for GEC protection, and size/type of equipment bond at the right." -

    1/2" EMT is good for (1) 1/0 conductor - which is big enough for a 900 kcmil svc conductor = >500A svc - so even the smallest size EMT would be plenty large enough for any GEC for this residential installation.

    RE: "doesn't look like it [EMT] has been supported properly" - another good catch - EMT needs to be secure within 3' of each end of the termination.

    BTW - not shown in the photo, but I would guess the GEC is not properly bonded to the EMT conduit where the GEC exits the EMT near the ground - this is a violation that is very common [NEC 250.64(E)].

    Like Jerry, these are my opinions. The difference is I am limited to applying code not fanatical opinion.


  35. #35
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    Default Re: Power for AC condensers

    I simply questioned the appropriateness of the use of thin-walled EMT due to its inability to resist severe physical damage, i.e. the grade level rock mulch, which requires maintenance, as we all know, on a regular basis, and in keeping with the geographical LOCATION of the O.P. as well as proximity to the service lateral installed (Article 358) ; and Yes, I was also questioning the size/type of the bonding jumper (solid copper conductor) to the raceway (emt) protection of/for the grounding electrode conductor raceway in regards to 250.64(E) as pictured in the bottom right of the cabinet enclosure and Article 358.

    Practical safeguarding, there are better alternatives which provide better damage protection at grade.

    M.S., you might find this brief article helpful regarding steel conduit. The Basics of Steel Conduit

    P.S. hard to tell colors on my monitor, was the (stranded) gec alum or copper? 18" from grade restriction outdoors.

    Last edited by H.G. Watson, Sr.; 07-30-2010 at 11:41 AM.

  36. #36
    Phil Brody's Avatar
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    Default Re: Power for AC condensers

    So there is no over current protection for the liquidtite strapped to the building, Hmmm


  37. #37
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    Default Re: Power for AC condensers

    Quote Originally Posted by Phil Brody View Post
    So there is no over current protection for the liquidtite strapped to the building, Hmmm
    Nonsense!


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    Default Re: Power for AC condensers

    Quote Originally Posted by Phil Brody View Post
    So there is no over current protection for the liquidtite strapped to the building, Hmmm
    The OCP is provided by the fused disconnects at the unit. This is no different than the main breaker protecting the service conductors above the meter.


  39. #39
    Phil Brody's Avatar
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    Default Re: Power for AC condensers

    How would the fused disconnects see a dead short prior to them ?


  40. #40
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    Default Re: Power for AC condensers

    Quote Originally Posted by Phil Brody View Post
    How would the fused disconnects see a dead short prior to them ?

    You are correct in what you say but the tap rule allows it. See excerpt below from post #6 above.

    B) Feeder Taps. Conductors shall be permitted to be tapped, without overcurrent protection at the tap


  41. #41
    Bert de Haan's Avatar
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    Default Re: Power for AC condensers

    Originally Posted by Rick Hurst
    Experience talking here. Never leave a good pair of sunglasses on top of a condensing unit.

    rick

    Quote Originally Posted by Wayne Carlisle View Post
    How many scrolled back up and opened the picture after reading this?

    Not me!!!!!!!!!
    I didn't either but that is because I saw the glasses and intended to make a smartalec comment. Rick beat me to it.


  42. #42
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    Question Re: Power for AC condensers

    Forgive me if its my glasses but looking at those pigtals coming off the main cable taps to the wire nuts: are BOTH condensers pulling through those single 10 gauge wires to the taps? If so, that ~6" pigtail could be seeing double current with no OCP, right?

    If not, I'll go back to my puzzles...

    Keep the fire in the fireplace.

  43. #43
    Phil Brody's Avatar
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    Default Re: Power for AC condensers

    Quote Originally Posted by James Duffin View Post
    You are correct in what you say but the tap rule allows it. See excerpt below from post #6 above.

    B) Feeder Taps. Conductors shall be permitted to be tapped, without overcurrent protection at the tap
    "At the Tap" once it leaves the enclosure I believe protection is need with that type conduit.


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    Default Re: Power for AC condensers

    Quote Originally Posted by Bob Harper View Post
    Forgive me if its my glasses but looking at those pigtals coming off the main cable taps to the wire nuts: are BOTH condensers pulling through those single 10 gauge wires to the taps? If so, that ~6" pigtail could be seeing double current with no OCP, right?

    If not, I'll go back to my puzzles...
    A couple of things come into play with that installation:
    - maximum rating of the overcurrent for the protection of the condenser unit, I presume the enclosures on the wall behind the condenser units have breakers or fuses which are properly rated
    - minimum circuit ampacity, I presume the conductor size of those two pieces meet minimum circuit ampacity
    - maximum rating of the overcurrent for protection of the tap conductors, this depends on if it meets the requirements of the various outside tap rules, and as I recall (I did not go back through and read all the posts) there is insufficient information there to know if it does or not.

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

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