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Thread: tap tap tap!

  1. #1
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    tap tap tap!

    A client of mine who is a solar contractor has installed the system depicted below. His approved drawing calls for a line side tap. The inspector says this is a supply side tap. It's on the line side of the panel but the supply side of the MB. What is the correct answer?

    If that is a supply side tap, does moving the tap to the line side of the MB make it a line side tap? Note that there is already a tap ahead of it to another panel.

    He used those taps that bite into the wire. If those are removed, can the insulation be repaired with tape (vinyl or rubber) and stay compliant? If not, could he leave them in place and just disconnect the tap wires and be compliant?

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  2. #2
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    Based on the diagram, the "panel B main breaker, which is not physically in panel B, is a service disconnect, with the main breaker in panel A also being a service disconnect. (Are they grouped?)
    That makes the PV connection a load side tap supplying the panel B bus but not located at the opposite end of the bus from the MB. Probably a violation, depending on the details of bus B rating, MB rating PV rating and sum of branch breakers.

    Sent from my XT1585 using Tapatalk

  3. #3
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    That's a load side connection, so it doesn't match the approved drawings.

    Is panel B itself MLO? If so, then the NEC requires the feeder downstream of the PV tap, and the bus in panel B, to be rated at least the sum of the Panel B service disconnect breaker size and 125% of the inverter output current.


    Cheers, Wayne

  4. #4
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    Quote Originally Posted by Coppersmith View Post

    He used those taps that bite into the wire. If those are removed, can the insulation be repaired with tape (vinyl or rubber) and stay compliant? If not, could he leave them in place and just disconnect the tap wires and be compliant?
    cup-L-taps, or similar ilk, can be removed, and the damaged
    insulation repaired as any other nicked insulation would be.

    or i suspect you could leave them on, removing the tap, and
    just torquing them down. i'd remove them and use 2 layers of
    half lapped scotch 33, and move on.
    ~New signature under construction.~
    ~~~~Please excuse the mess.~~~~

  5. #5
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    Quote Originally Posted by Coppersmith View Post
    A client of mine who is a solar contractor has installed the system depicted below. His approved drawing calls for a line side tap. The inspector says this is a supply side tap. It's on the line side of the panel but the [load] side of the MB. What is the correct answer?

    If that is a supply side tap, does moving the tap to the line side of the MB make it a line side tap? Note that there is already a tap ahead of it to another panel.


    Click image for larger version. 

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    Terminology seems off the mark in your post. 'Line' and 'supply' are synonyms here. In the above quote I changed one instance of 'supply' to 'load' because that's what your diagram indeed shows (a tap on the load side of the MB, not the supply side]. In the other instances of 'supply' some clarification might be in order. What exactly did the inspector call which?

    He used those taps that bite into the wire. If those are removed, can the insulation be repaired with tape (vinyl or rubber) and stay compliant?
    In my opinion yes.

    If not, could he leave them in place and just disconnect the tap wires and be compliant?
    I'd be a bit more concerned about exposed live parts inside those than conductor insulation repaired with tape. Still calls for tape around open holes, in my opinion.

  6. #6
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    Quote Originally Posted by jaggedben View Post
    Terminology seems off the mark in your post. 'Line' and 'supply' are synonyms here.
    After a bit of research I agree. I was using the terminology the solar contractor told me. I also reviewed the drawing and found the engineer said "supply side" and showed a diagram where the taps are between the meter and the panel main. He doesn't show the separate main breaker before the panel.

    Quote Originally Posted by GoldDigger View Post
    Based on the diagram, the "panel B main breaker, which is not physically in panel B, is a service disconnect, with the main breaker in panel A also being a service disconnect.
    Quote Originally Posted by wwhitney View Post
    That's a load side connection, so it doesn't match the approved drawings.
    So if we move the tap above the "service disconnect" (which would be right after the meter), does that make it line/supply side?

    Quote Originally Posted by GoldDigger View Post
    (Are they grouped?)
    No they are not, but pre-exisiting so not an issue I hope.

  7. #7
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    Quote Originally Posted by Coppersmith View Post
    So if we move the tap above the "service disconnect" (which would be right after the meter), does that make it line/supply side?
    Yes.

  8. #8
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    Are these something useful?>>>
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    ~RJ~

  9. #9
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    Quote Originally Posted by romex jockey View Post
    Are these something useful?>>>
    Click image for larger version. 

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    ~RJ~
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    Derek

  10. #10
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    Quote Originally Posted by jumper View Post
    What are they?
    They appear to be replacements for the tops of the lugs inside the meter can that allow the attachment of a tap conductor. I've never seen the tap done inside the meter can but I can't think of a reason you couldn't do it.

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