120 volt duplex receptacle with the link split has 2 circuits feeding it

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rayertz

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120 volt duplex receptacle with the link split has 2 circuits feeding it with different phases and a common neutral.
Is this acceptable per the NEC
 
rayertz said:
120 volt duplex receptacle with the link split has 2 circuits feeding it with different phases and a common neutral.
Is this acceptable per the NEC
Click to expand...

Sure, more recent code years have required a common means of disconnect for that. Handle ties or multi-pole breakers will work.
 
GoldDigger said:
Common trip would only be required for phase to phase loads. If there are only phase to neutral loads (as they would have to be from a split duplex receptacle) then common manual operation is good enough.
Click to expand...

The OP said "common neutral", I take that to mean this is a MWB set up. Common trip required, yes?
 
From 2011

210.4 Multiwire Branch Circuits.

(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.

Informational Note: See 240.15(B) for information on the
use of single-pole circuit breakers as the disconnecting
means.
Click to expand...


240.15 Ungrounded Conductors.

(B) Circuit Breaker as Overcurrent Device. Circuit breakers
shall open all ungrounded conductors of the circuit both
manually and automatically unless otherwise permitted in
240.15(B)(1), (B)(2), (B)(3), and (B)(4).

(1) Multiwire Branch Circuit. Individual single-pole circuit
breakers, with identified handle ties, shall be permitted
as the protection for each ungrounded conductor of multiwire
branch circuits that serve only single-phase line to neutral
loads.
Click to expand...
 
I know OP specified MWBC, but more general requirement exists

I know OP specified MWBC, but more general requirement exists

If it is not a MWBC, then consider the following:

210.7 Multiple Branch Circuits. Where two or more branch circuits supply devices or equipment on the same yoke or mounting strap, a means to simultaneously disconnect the ungrounded conductors supplying those devices shall be provided at the point at which the branch circuits originate.
 
fmtjfw said:
If it is not a MWBC, then consider the following:

210.7 Multiple Branch Circuits. Where two or more branch circuits supply devices or equipment on the same yoke or mounting strap, a means to simultaneously disconnect the ungrounded conductors supplying those devices shall be provided at the point at which the branch circuits originate.
Click to expand...

And handle ties still meet that requirement.

Life is good! :)
 
iwire said:
From 2011
Click to expand...

OK, thanks for the citation. I don't deal with MWBC's so I'm curious about a practical matter. If I use a handle tie on two single pole breakers and one trips, is the handle movement sufficient to trip the other?
 
gadfly56 said:
If I use a handle tie on two single pole breakers and one trips, is the handle movement sufficient to trip the other?
Click to expand...

It may or may not trip the other.

But the NEC is not requiring both to trip due to a short or overload, the NEC is just requiring that when a human goes to shut it off that all legs will open.

Also consider the fact a MWBC could come from a fuse panel, in that case you would have to provide a two or three pole switch beside the panel to meet the requirement.

Notice how carefully this is worded

a means that will simultaneously disconnect all ungrounded conductors at the point where the branch circuit originates
Click to expand...

Really not telling you how, just that it has to happen and it better be at the panel.
 
rayertz said:
120 volt duplex receptacle with the link split has 2 circuits feeding it with different phases and a common neutral.
Is this acceptable per the NEC
Click to expand...
I agree with most of what has been said so far, and want to add this is one reason the removable link is there in the first place. Even if there were such a beast as a three plex receptacle (maybe there is), you could have one common neutral and all three phases of a three phase system powering each of the three "ports".
 
this was of interest to me too. what I wonder is I assume an afci is not going to work on this?

ron g
 
As long as the two circuits form an MWBC, with no crossed neutrals, you can use a GFCI or AFCI breaker with two poles.
Or if they are not an MWBC (neutral strap cut too), then you can use an AFCI breaker with no GF element.
 
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