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  1. #1
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    Default Fix for a triple tap in a power panel

    Saw a triple tap on a 20 amp breaker and several double taps at an inspection a few months ago. Returned today to confirm if repairs were done. Expected to see an installed auxiliary panel but a licensed electrician took the three wires from the triple tap, wire nutted them together to another 12 gauge wire and ran the single wire to the 20 amp breaker. Said that was legal. Did the same with the double taps. This sounds crazy to me but I am not a licensed electrician. So who is crazy, me or the electrician. (hope its not me!)

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  2. #2
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    Default Re: Fix for a triple tap in a power panel

    If done within the prescribed limitations of wire size, ampacity, load requirements (for the newly added conductors) box fill, etc. etc. what you described could be fine. Wire nuts, splices and connectors are allowed in the panel.

    If there are available breaker slots, and the panelboard supports another breaker, that option is also available.

    I don't do load calculations or try to figure out what the branch circuits are feeding, so it needs a sparky to make that decision.

    How do you suppose a traditional branch circuit is routed in the system? The wire runs to a junction or device, is connected or joined together, and then runs to another junction or device downstream. It's all the same concept.


  3. #3
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    Default Re: Fix for a triple tap in a power panel

    Sounds right, as Dom said.

    If the breaker keeps tripping then they would need to separate the one circuit into separate circuits on their own breaker.

    Here is an example of what I just put in my garage this past week. I installed two 50 amp 240 volt receptacles at different locations for my welder, which only needs 30 amps 240 volts, using 10-2 w/g NM cable, with both wired nutted together as you described, to one 30 amp 2-pole breaker.

    I'm only going to use the welder from one of the receptacles at a time, which receptacle depends on where in the garage.

    ~~~~~~~

    I see some eyebrows raised.

    50 amp receptacle on only a 30 amp circuit? Yep.

    The 30 amp circuit conductors are protected by a 30 breaker. The 50 amp receptacles are also protected by the 30 amp breaker. All per the code.

    IF ... if it was a 30 amp receptacle on a circuit protected by a 50 amp breaker, that would be like putting #10 (30 amp rated) conductors on a 50 amp breaker ... and would not be good.

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

  4. #4
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    Default Re: Fix for a triple tap in a power panel

    Quote Originally Posted by Jerry Peck View Post
    ~~~~~~~

    I see some eyebrows raised.

    50 amp receptacle on only a 30 amp circuit? Yep.

    The 30 amp circuit conductors are protected by a 30 breaker. The 50 amp receptacles are also protected by the 30 amp breaker. All per the code.

    IF ... if it was a 30 amp receptacle on a circuit protected by a 50 amp breaker, that would be like putting #10 (30 amp rated) conductors on a 50 amp breaker ... and would not be good.
    Rightly so eyebrows should be raised. It is a code violation. See Table 210.21(B)(3)

    There is an exception to the rule that is cited later in this post. This is not a code violation.

    Last edited by Jim Port; 07-20-2022 at 05:25 PM.
    All answers based on unamended National Electrical codes.

  5. #5
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    Default Re: Fix for a triple tap in a power panel

    Quote Originally Posted by Jim Port View Post
    Rightly so eyebrows should be raised. It is a code violation. See Table 210.21(B)(3).
    Look at 210.21 Outlet Devices. Outlet devices shall have an ampere rating that is not less than the load served and shall comply with 210.21(A) and (B).

    210.21(B) Receptacles.
    (3) Receptacle Ratings.
    Exception No. 1: (Receptacles ... blah, blah, blah, ... shall be permitted to have ampere ratings not less than the minimum branch-circuit conductor ampacity determined by 630.11(A) or (B) for arc welders.

    630.11(A) Individual Welders.

    (Rated voltage as used is "240 VAC / 60 Hz", rated primary current amperes is "25.5 A at 200 A".)

    My welder's duty cycle is 25% to 100% depending on its use; my 30 amp circuit conductors will take use at 100% duty cycle ("25% @ 200 A | 100% @ 115 A").

    I likely never even reach 25% duty cycle in my use (manual states "Avoid damage to the Welder by not welding for morethan the prescribed duty cycle time. The Duty Cycledefines the number of minutes, within a 10 minuteperiod, during which a given welder can produce aparticular welding current without overheating." and "25% Use at 200 AFor 10 continuous Minutes [means] 2-1/2MinutesWelding7-1/2MinutesResting").

    I doubt that I have ever welded "continuously" for even 1 minute. In short welds, stop, move to next location, short weld, stop, move to next location ... maybe welding a total of 2-3 minutes over that 10 minute span, at amperage low enough to fall within the 100% duty cycle allowance - i.e., I might hit the 25% duty cycle occasionally, but be within the 100% duty cycle capabilities of the welder. Worst case real life duty cycle may be 25%; worst case label duty cycle is 100%, and the code goes by the label.

    My welder: ( https://www.harborfreight.com/omnipr...put-57812.html )

    Jim, Please correct me if my calculations are incorrect, and explain where I have calculated something incorrectly. Thank you.

    I still say that my installation is code compliant - explain where it is not.

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

  6. #6
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    Default Re: Fix for a triple tap in a power panel

    Ok,

    I'm way out of my depth here, but I thought I would toss this in. What about 210.23?

    210.23(B) 30-Ampere Branch Circuits. A 30-ampere branch circuit shall be permitted to supply fixed lighting units with heavy-duty lampholders in other than a dwelling unit(s) or utilization equipment in any occupancy. A rating of any one cord-and-plug-connected utilization equipment shall not exceed 80 percent of the branch-circuit ampere rating.

    Or is that overridden by 630.11(A) which is specific to arc welders?

    Last edited by Gunnar Alquist; 07-13-2022 at 10:11 AM.
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  7. #7
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    Default Re: Fix for a triple tap in a power panel

    Quote Originally Posted by Gunnar Alquist View Post
    210.23(B) 30-Ampere Branch Circuits. ... A rating of any one cord-and-plug-connected utilization equipment shall not exceed 80 percent of the branch-circuit ampere rating.
    Ahh ... that "of the branch-circuit ampere rating" 'thing' ...

    For branch-circuit ampere ratings, which are different than overcurrent protection ratings, you go to Table 310.15(B)(16) ... (which used to be Table 310.16) ... which lists 10 AWG as having a rating of 30 amps for 60C insulation, 35 amps for 75C, or 40 amps for 90C. Most insulation out there now is rated for 90 degrees C (most individual conductors are dual rated as THHN/THWN). The conductors in NM-B (which is what I used) have conductor insulation rated for 90 degrees C.

    Thus the "branch-circuit ampere rating", for 90C rated conductor insulation, is 40 amps, with 80% of 40 amps being 32 amps. and, if run through attics (mine are not), then apply ambient derating to the 40 amps (my garage gets to 85-86F, which has no derating, but just for fun, lets go to the next step up to 87-95F which has a derating factor of 0.96), and if bundled or lack of maintaining spacing applies, derate again for that (mine do not have that issue either). Thus the 10 AWG NM-B ampere rating with a derating to 96%, is 40 amps X 0.96 = 38.4 amps, and then apply the 80% factor for 38.4 X 0.80 = 30.72 amps.

    My welder rating was 25.5 amps is well within the 210.23(B) allowance of 30.72 amps during the summer. During the winter, the garage gets below 50F, and below 50F the derating factor allows for an increase as the factor is 1.35, or 40 X 1.35 = 54 amps ... but one should always apply the derating for the lowest amperage for the highest temperature - can't count on someone "only using the circuit during the winter" (unless it is located where it is "always winter").

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

  8. #8
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    Default Re: Fix for a triple tap in a power panel

    Ok, now my head hurts.

    I thought 240.4(D) said that 14, 12, & 10 conductors (among others) could not exceed 15A, 20A, & 30A, no matter what the insulation rating was.

    Again, I am out of my depth.

    240.4 Protection of Conductors. Conductors, other than flexible cords, flexible cables, and fixture wires, shall be protected against overcurrent in accordance with their ampacities specified in 310.15, unless otherwise permitted or required in 240.4(A) through (G).

    (D) Small Conductors. Unless specifically permitted in 240.4(E) or (G), the overcurrent protection shall not exceed that required by (D)(1) through (D)(7) after any correction factors for ambient temperature and number of conductors have been applied.

    (7) 10 AWG Copper. 30 amperes


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  9. #9
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    Default Re: Fix for a triple tap in a power panel

    Gunnar,

    That's why I started with this:

    Quote Originally Posted by Jerry Peck View Post
    For branch-circuit ampere ratings, which are different than overcurrent protection ratings, .
    Overcurrent protection size of the circuit is not the same as the rating of the circuit.

    Think of it this way: the conductor rating needs to be at least as great as the overcorrent protection rating.

    The overcurrent protection rating for small conductors is as you posted (except those are maximum overcurrent protection ratings for those small conductors not suitableforthose in evety csse); however, are you allowed to use 10 AWG (30 amp) on a 15 amp breaker? Sure.

    In fact, there are cases (many more than almost every electrician will think of) where using 10 AWG on a 15 amp breaker is required if proper derating is applied. Is it ever done? I've never seen it done, but I have pointed such derating out to many contractors over the years, with the solution being as simple as unbundling 20-30 NM cables (which with 2 conductors in each is 40-60 conductors and maximum derating, which I think is derated to 35%). Combine that with derating through 130-140F attics makes 14 AWG totally useless, same for 12 AWG.

    Pulling numbers out of my mind as I don't have my codes with me: 12 AWG NM- B, for derating purposes, may be as much as 35 amps; derate to 76% for those attics equals 35 X 76% = 26.6 amps; then derate for 40 or more conductors equals 26.6 X 35% = 9.31 amp, which isn't much good for anything.

    But that is branch-circuit ampacity, overcurrent protection is the breaker or fuse size, which should be selected for branch-circuit ampacity.

    Typing on my phone, may have to edit when I get to my computer later.

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

  10. #10
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    Default Re: Fix for a triple tap in a power panel

    Jerry,

    I am going to have to take your word for it right now. For some reason, my brain is stuck in the slow lane and I cannot grasp anything more difficult than trying to figure out what I'm going to cook for dinner.

    I'll try to power through this over the weekend.

    Department of Redundancy Department
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  11. #11
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    Default Re: Fix for a triple tap in a power panel

    Gunnar, start with 310.15(B)(2) and (3). ake sure to review Table 310.15(B)(2)(a) and Table 310.15(B)(3)(a).

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

  12. #12
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    Default Re: Fix for a triple tap in a power panel

    Just to (hyuk, hyuk) help out here, not for Jerry's case but for more general application, a reminder: if we actually need the full rating of a 90 deg C conductor, not as a place to start out derating but as the actual ampacity, everything needs listing for use at that temperature rating: the receptacle or other outlet connection, the panelboard, the CB or fuseholder.


  13. #13

    Default Re: Fix for a triple tap in a power panel

    i love technical people




    http://decorbest-en.com


  14. #14
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    Exclamation Re: Fix for a triple tap in a power panel

    Quote Originally Posted by Jerry Peck View Post
    I still say that my installation is code compliant - explain where it is not.
    Response from NFPA: (the two "?" are where the response had the "R" registered symbol)

    "
    Thank you for your question on the 2017 edition of NFPA 70?, National Electrical Code?.

    Exception No. 1 permits receptacles installed exclusively for one or more arc welders to be rated not less than the minimum ampacity for the welder branch circuit conductors determined in accordance with 630.11(A) or (B). This exception provides for receptacle ratings different than those specified in Table 210.21(B)(3).
    "

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

  15. #15
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    Default Re: Fix for a triple tap in a power panel

    Quote Originally Posted by Jerry Peck View Post
    Response from NFPA: (the two "?" are where the response had the "R" registered symbol)

    "
    Thank you for your question on the 2017 edition of NFPA 70?, National Electrical Code?.

    Exception No. 1 permits receptacles installed exclusively for one or more arc welders to be rated not less than the minimum ampacity for the welder branch circuit conductors determined in accordance with 630.11(A) or (B). This exception provides for receptacle ratings different than those specified in Table 210.21(B)(3).
    "
    Thank you for the cite of the exception.

    All answers based on unamended National Electrical codes.

  16. #16
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    Default Re: Fix for a triple tap in a power panel

    Quote Originally Posted by Jim Port View Post
    Thank you for the cite of the exception.
    I gave that in post #5.

    210.21(B) Receptacles.
    (3) Receptacle Ratings.
    Exception No. 1: (Receptacles ... blah, blah, blah, ... shall be permitted to have ampere ratings not less than the minimum branch-circuit conductor ampacity determined by 630.11(A) or (B) for arc welders.

    630.11(A) Individual Welders.


    It's part of 630.11(A).



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

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