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-   -   Arcfault breakers in subpanel (https://www.askmehelpdesk.com/showthread.php?t=525926)

  • Nov 14, 2010, 06:47 PM
    leftyspc
    Arcfault breakers in subpanel
    I am turning a small small room into part of a greatroom adition. A dozen lines run over the trusses. By adding a sub panel I will open up space in main and will not need junktion boxes. Questionn is will I need to arcfault all these old curcits to stay in code
  • Nov 14, 2010, 09:30 PM
    stanfortyman

    No, you are not running new circuits so arc faults should not be required.
  • Nov 15, 2010, 08:32 AM
    donf

    If, you are moving circuits from the main panel into the sub panel, yes, you will need to install AFCI breakers.

    You are in effect changing the circuit design.
  • Nov 15, 2010, 10:24 AM
    stanfortyman
    Quote:

    Originally Posted by donf View Post
    If, you are moving circuits from the main panel into the sub panel, yes, you will need to install AFCI breakers.

    You are in effect changing the circuit design.

    Can you confirm this Don?
    How do you feel this is changing the circuit design?

    I know of only very rare instances where a panel change would require AFCI breakers on existing circuits.
  • Nov 15, 2010, 10:45 AM
    donf

    Stan,

    To me, if you take an existing circuit out of the main service panel to create a sub-panel feed, then you have a new circuit design.

    If you then take an existing circuit and place it into a sub-panel you have physically changed its design and should therefore upgrade the circuit.

    AFCI are for the safety of the user by preventing a fire.

    Am I being to critical? If so, I will defer to you.
  • Nov 15, 2010, 11:22 AM
    stanfortyman

    All I will say is I completely disagree. The circuit design is not being changed at all, just it's point of origin.
  • Nov 15, 2010, 11:22 AM
    donf

    Stan,

    I did a rudimentary straw pole of local electricians (4) and the local city inspector (not available until 4:00 P.M.).

    Anyway two of the four electrical companies said yes, but only iuse AFCI breakers for any of the circuits go to bedrooms. (Virginia is still on the 2005 Code. The Commonwealth will change to 2008 when the next Building Codes are adopted.)

    One company said, "No" no breaker change required.

    One company said:"For $1,859 +/-, to R&R the panel and meter base.

    The reasoning, was that if the panel is out of space, and you remove some circuits to a sub, you may actually overload the panel main breaker. Solution, put in a larger 200 amp panel with more space.

    Go figure! I think I'll wait for the inspector.
  • Nov 15, 2010, 11:35 AM
    stanfortyman
    Quote:

    Originally Posted by donf View Post

    The reasoning, was that if the panel is out of space, and you remove some circuits to a sub, you may actually overload the panel main breaker. Solution, put in a larger 200 amp panel with more space.

    Makes absolutely no sense. What is the difference between more space in a sub-panel and more space in a main panel?
    Also, just adding circuits does NOT mean you are adding load.
  • Nov 15, 2010, 11:48 AM
    donf

    Stan,

    Please do not shoot the messenger. I'm just repeating what I was told by the electrical contractor.

    In no way do I agree with his statements. Come to think of it, nor would I use this guy for any electrical work.
  • Nov 15, 2010, 02:52 PM
    tkrussell
    At first I would have taken the stance that the circuit did not change, so AFCI should not be required, however, I do see the point of changing the breaker to AFCI, since that is what is being changed.

    Since AFCI is the standard now, makes sense to take the opportunity to upgrade the protection.

    This, however, now can only be required if the circuit is already a standard two wire circuit with the proper outlets classified for that circuit, AFCI ready, so to speak.

    Changing the breaker to AFCI cannot make a homeowner upgrade the circuit, which certainly would not be practical.

    Tough call, I suggest that Lefty check with is local inspector for his opinion. Existing installations must always refer to the local authority, as the Code is only for new installations regarding issues such as this, or vague in respect to existing installations.


    Then again, the original style breaker is part of the original circuit design, and should not need to be changed.

    I am going back to my original gut reaction, no need to change to AFCI.

    Glad I am not a practicing inspector. Going to piss off someone on this topic.

    I don't buy Don's inspector's answer, down right silly answer if you ask me.

    Some other discussions on the topic:


    Panel Replacement & MWBC/AFCI [Archive] - Mike Holt's Forum

    Behind the 2005 NEC Changes: 210.12 AFCIs
  • Nov 15, 2010, 03:44 PM
    donf

    Drum roll please:

    I finally got to speak with the city's electrical inspection department this afternoon.

    He says, First step would be to submit a load calculation along with the permit application. If this is not done, no permit will be issued.

    Next, since Virginia follows the 2005 NEC, only a new circuit to a bedroom or any circuit moved to the sub-panel from the main panel that goes to a bedroom would require a combination AFCI breaker.

    If Virginia were at the 2008 Code (expected shortly) then all circuits placed into the new sub-panel would require a combination AFCI breaker, if applicable.

    TK - Stan, the statements you are talking about were made by a local electrical contractor, not an inspector.

    The inspector was out of the office until 4:00 P.M. EDT.

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