Robert E Lee Posted September 25, 2012 Report Share Posted September 25, 2012 My son-in-law in is the process of installing a generator backup system at their home. There are (4) multi-wire circuits that he plans on moving over to the transfer panel. When he went for the permit today he was told that he will need to use "handle ties" on the breakers of these multi-wire circuits. I have never been aware of the need for "handle ties" on multi-wire circuits other than on the disposal/dishwasher outlet. They are located in WA state, in a suburb of Seattle, anyone else ever run into something like this? Quote Link to comment Share on other sites More sharing options...
John Dirks Jr Posted September 25, 2012 Report Share Posted September 25, 2012 I've only seen handle ties for a multi wire circuit once in five years of inspecting. As you said Robert, it was for a dishwasher/disposal combination on a 2010 new home construction. Since that time I've done other new homes and never saw the ties again. Quote Link to comment Share on other sites More sharing options...
Brandon Whitmore Posted September 25, 2012 Report Share Posted September 25, 2012 210.4 Multiwire Branch Circuits. (A) General. Branch circuits recognized by this article shall be permitted as multiwire circuits. A multiwire circuit shall be permitted to be considered as multiple circuits. All conductors of a multiwire branch circuit shall originate from the same panelboard or similar distribution equip- ment. FPN: A 3-phase, 4-wire, wye-connected power system used to supply power to nonlinear loads may necessitate that the power system design allow for the possibility of high harmonic currents on the neutral conductor. (B) Disconnecting Means. Each multiwire branch circuit shall be provided with a means that will simultaneously disconnect all ungrounded conductors at the point where the branch circuit originates. © Line-to-Neutral Loads. Multiwire branch circuits shall supply only line-to-neutral loads. Exception No. 1: A multiwire branch circuit that supplies only one utilization equipment. Exception No. 2: Where all ungrounded conductors of the multiwire branch circuit are opened simultaneously by the branch-circuit overcurrent device. FPN: See 300.13(B) for continuity of grounded conductor on multiwire circuits. (D) Grouping. The ungrounded and grounded conductors of each multiwire branch circuit shall be grouped by wire ties or similar means in at least one location within the panelboard or other point of origination. Exception: The requirement for grouping shall not apply if the circuit enters from a cable or raceway unique to the circuit that makes the grouping obvious. Quote Link to comment Share on other sites More sharing options...
Robert E Lee Posted September 25, 2012 Author Report Share Posted September 25, 2012 (B) Disconnecting Means. Each multiwire branch circuit shall be provided with a means that will simultaneously disconnect all ungrounded conductors at the point where the branch circuit originates. Brandon, what version of the NEC is the para from? As almost all of the circuits in their existing panel are multi-wire circuits and none of the breakers have "handle ties". Quote Link to comment Share on other sites More sharing options...
Bill Kibbel Posted September 25, 2012 Report Share Posted September 25, 2012 It looks like it first appeared in 2008. Quote Link to comment Share on other sites More sharing options...
Robert E Lee Posted September 25, 2012 Author Report Share Posted September 25, 2012 Thanks guys, the home was built in 1999 so wouldn't have been required on the existing panel, but need to do so on the transfer panel. Quote Link to comment Share on other sites More sharing options...
Jeff Remas Posted October 11, 2012 Report Share Posted October 11, 2012 Yep, 2008 was the change with the NFPA 70 Quote Link to comment Share on other sites More sharing options...
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