Split receptacles, double pole breakers and multiple circuits in a junction box.

morganhammer

So I'm trying to figure out the code for when to use double pole breakers on single leg circuits with regard to multiple circuits in one junction box.
Lets use the last example I had to deal with. If I had a fully split receptacle, as in two hot and two neutral, do these circuits need to be on a double pole breaker? And if not, does it make sense to put the circuits on the same leg or opposing legs? It seems safer to me ,considering that each circuit has it's own neutral, to keep the two circuits on the same leg as that would only ever give that junction box 120 v.
And considering the above, is there need to use double pole breakers for multiple circuits in one junction box that do not share a device? I assume not.
I had more questions in this vein but I think it would be appropriate to start another thread, no?

AllanJ

Two feeds with separate neutrals and on separate breakers can come into the same junction box. But if the two hot feeds are connected to the two halves of a one duplex receptacle then the feeds should connect to a double breaker with handles tied together.

With separate neutrals (break the tabs on both sides of a duplex receptacle if you split the halves) the hots may or may not be on the same side (leg) of the 120/240 volt service. With a shared neutral, the two hots must be in the same cable or conduit and be on opposite sides of the 120/240 volt service.

__________________
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Chevyman30571

its called a mwbc(multi wire branch circuit) but you better know what you are doing otherwise you can cause a lot of destruction. all neutrals must be pigtailed.

morganhammer

Thanks for the response guys.
Chevy, I was under the impression that a MWBC was describing a shared neutral situation and only that. Please tell me if I am missing something. The situation I described is a split receptacle split between two separate circuits each with it's own neutral. I did not pigtail the neutrals because in my understanding that would initiate an arc fault trip seeing as one neutral would run through the AFCI and the other would not.
I think Allen addresses my question but I am still left confused. I read a contradiction in your answer.
"..if the two hot feeds are connected to the two halves of a one duplex receptacle then the feeds should connect to a double breaker with handles tied together.
With separate neutrals (break the tabs on both sides of a duplex receptacle if you split the halves) the hots may or may not be on the same side (leg) of the 120/240 volt service."
In my described situation the two hot feeds are connected to the two halves of a duplex receptacle. Hence by your description requires a double breaker/ handle tie. How then could it be possible to to be on the same leg if it is indeed a double breaker? How may both halves of the same receptecle be on the same leg if the two hot feeds (and two neutrals) that are connected to either half of said receptacle require a double pole/ handle tied breaker? Seeing as the double pole forces using opposing legs, as designed.
If it helps let me expound on the specifics of my situation. There is one duplex receptacle in the corner of a bedroom. The top half is connected to constant power from a outlet circuit and the bottom half is switched power from the lighting circuit. The top outlet circuit is AFCI protected and the bottom/switched half is not. (somehow the inspector has allowed non AFCI due the timing of permit request). Yes both tabs will be removed. Each run is at it's termination so no pigtails (except ground wires).

So to be clear, it is my understanding that, as Allen has stated, since the hot feeds connect to the two halves of one receptacle it must use a double pole breaker. Defacto this means they are on opposing legs.

AllanJ

On some panels, the two fins spanned by a double wide breaker might be on the same side of the service depending on the exact position of the breaker. For a shared neutral, you must choose a position where the breaker spans fins on opposite sides of the 120/240 volt service. For separate neutrals it does not matter.

__________________
The disadvantages of crab apple trees. In summer, the apples are too sour to pick and eat. In winter the birds come and leave dropping all over the place.

a7ecorsair

Allan,
I think the OP is questioning your usage of should vs. must.
Is there a requirement in the code that mandates a handle tied breaker? I know it would work but there is the issue that someone could turned off one breaker and think the outlet is dead only to be surprised when they pull the receptacle out.

Red Squirrel

I had that happen to me before. I was shocked to find out there was two circuits in there.