4 circuit Furniture feed breaker tie.

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I have a 4 circuit furniture feed and a plan check correction requiring that I tie all four breakers together so they operate simultaneously. But, as far as I know there is no such thing as a 4 circuit breaker tie.

This is per 210.4(B) of the 2005 NEC

How do I deal with this?

Thanks,
Dean
 

charlie b

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How do I deal with this?
By informing the plan reviewer that a set of cubicle furniture does not constitute a "yoke." So what is a "yoke"? A duplex receptacle has two places to plug something in, and the two are attached to a common yoke. So as long as you don't have a "four-plex" receptacle built into the furniture, with one circuit feeding each of the four outlets on the same yoke, then 210.4(B) does not apply, and you don't need a common handle tie for the four breakers.


Welcome to the forum.
 
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raider1

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Welcome to the forum.:)

For office furnishings and wired partitions you need to look at 605.6 and 605.7. These sections require that multiwire branch circuits that supply fixed or freestanding partitions be provided with a means to simultaneously disconnect all ungrounded conductors.

These were new sections added to the 2005 NEC.

Chris
 

iwire

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If the furniture is of the '3 + 1' design the 3 breakers service the 3 phase multiwire branch circuit must be tied together, the fourth circuit is a standard two wire circuit and is not required to be tied to the other 3 breakers.

Often the 3 pole multiwire circuit comes from a 'dirty power' panel and the forth wire wire circuit will originate in a 'clean' power panel making the linking of the breakers imposable. (Regardless of the set up it is not required)
 

charlie b

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And article 210.4(B) of the 2008 version requires any multi-wire branch circuits to have common trips. But the original question did not say that there were any MWBCs involved. So let's pin down this issue: Do the four circuits include separate neutral wires, or are they set up as one or more MWBCs?
 

iwire

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And article 210.4(B) of the 2008 version requires any multi-wire branch circuits to have common trips. But the original question did not say that there were any MWBCs involved. So let's pin down this issue: Do the four circuits include separate neutral wires, or are they set up as one or more MWBCs?


I understand your point but having installed way to many office cubes I have never seen a four 'two wire' circuit version. Of course I have not seen everything.

But as Chris mentioned Article 605 comes into play here, it required handle ties even before the changes in 2008s 210.4(B):)
 
Thank for the response...

the furniture specs area as follows:

4-circuit system provides four phase conductors, one shared neutral conductor, one isolated neutral conductor and two ground conductors
 

iwire

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Yeah, most furniture manufacturers call that 3 +1

Usually you have black, red, blue, white and green for the multi wire

Pink, white with tracer and green with yellow tracer for the two wire circuit.
 

charlie b

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. . . having installed way to many office cubes I have never seen a four 'two wire' circuit version. Of course I have not seen everything.
If you get a design from one of the guys in my office, you are likely to see a two "three wire" circuit version. He likes the notion of creating MWBCs using hot-hot-neutral, hot-neutral (if there are three circuits), or hot-hot-neutral, hot-hot-neutral (if there are four circuits).
 

Sierrasparky

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I can see the issue of disconnection of all circuits to the furniture simultaneously but that is not a code requirement as of yet.
If the AHJ wants to modify the code then they need to place is writing for all the EC in the area.

Otherwise PASS that portion of the project.
 

charlie b

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I can see the issue of disconnection of all circuits to the furniture simultaneously but that is not a code requirement as of yet.
I can't, and I hope it doesn't become code. I don't think the owner will be happy with having to shut down all workstations in an open office area, just to work on one receptacle served by one breaker.


I can easily see a single sleeve in the floor carrying 8 or more circuits up into a central point in a cubicle arrangement, with the conductors spreading out from that point to serve 16 or more workstations. I can do that with MWBCs, and I can handle-tie the breakers in sets of 2 or 3 as appropriate. But I won't be able to handle tie 8 breakers together. That is OK, because I can't have a MWBC with more than 3 circuits anyway. You might try pointing that out to the plan reviewer: the definition of MWBC essentially prohibits the circuit from including more than 3 hot conductors from 3 separate breakers.
 

Mike01

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Common Trips?

Common Trips?

And article 210.4(B) of the 2008 version requires any multi-wire branch circuits to have common trips. But the original question did not say that there were any MWBCs involved. So let's pin down this issue: Do the four circuits include separate neutral wires, or are they set up as one or more MWBCs?

?Common trips? I ran into this issue on a project (see my post here: http://forums.mikeholt.com/showthread.php?t=116247) , I agree only the three breakers need to be indicated as a mulit-wire circuit and tied together. But this does not create a ?common trip? based on the manufacturers information and the UL white book (see circuit breakers (DIVQ) discusses applications of ?common trip?) a tie handle does not create a point or common trip because one breaker trips does not mean that all the positions will trip, (open different than tripped). I interpret this to be more of an indication to an electrician who is preparing to work on the equipment to visually identify that the circuit contains a multi-wire branch circuit it is not the intent to make all the positions open at once under a fault condition. In fact most manufacturers? literature indicates this. Also not all manufacturers make handle ties for their breakers some insist a 3-pole breaker be used but then you lose the flexibility of three 1-pole breakers when things get remodeled also pay attention to the manufacturers handle tie most will make one for two positions (two single pole breakers) and a separate one for tying three poles (three single pole breakers) together as the device used to tie two breakers together will not be listed for use with three breakers. Installation instructions from one manufacturer (square ?D?) ?For use on three one-pole circuit breakers. Handle can be locked in OFF (O) or ON (I) position. If locked ON (I), attachment will not prevent circuit breaker from opening if tripped by circuit conditions or by pressing Push-to-Test button on QO-AFI, QO-GFI or QO-EPD circuit breakers. NOTE: Handle tie does not provide common trip protection.? This seems to be the norm along with Siemens, and GE equipment however Eaton (Cutler-Hammer) does not make handle ties for their breakers. Why I am not sure. Square ?D? makes two versions one for tying two single pole breakers together and one for tying three single pole breakers together. (QO3HT & QO1HT) the key here is a ?listed? device. I guess before I would start the project if the panels are existing make sure you can get the tie for existing breaker types and for new specifications make sure that the manufacturers specified can provide these, or spec 3-pole breakers instead. Just my 2 cents.
Question when refering to
 

Sierrasparky

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I can't, and I hope it doesn't become code. I don't think the owner will be happy with having to shut down all workstations in an open office area, just to work on one receptacle served by one breaker.

I was not advocating the situation I was just making a point that some folks on the rule making board could add this to the list of impractical codes. :cool:
 

infinity

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Only the 3 circuit in the 3+1 configuration needs to be tied together (NEC 605.6 and 605.7). This is a multiwire branch circuit.

Charles gave the Articles as they were added to the 2005 NEC. Since the 2008 now contains 210.4(B) which requires the simultaneous disconnect of all MWBC's the requirements in article 605 have become moot. I wouldn't be surprised to see them removed from a future edition of the NEC.
 
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