Tagged for multiwire branch circuit

crtemp

Senior Member
Location
Wa state
I just got tagged for not having all of my neutrals pigtailed down in a plug box. I did have the 3 wire neutral and the neutral going to the other circuit (from the red of the 3 wire) pigtailed though, just not the other wire that is on the same circuit as the black of the 3 wire. This has always been good enough for the last 5 years I've been doing mwbc's. I just find that it is less of a chance of a wire slipping out of the wire nut when I only tie three wires together instead of four. Is this inspector just being difficult?
 

GoldDigger

Moderator
Staff member
I just got tagged for not having all of my neutrals pigtailed down in a plug box. I did have the 3 wire neutral and the neutral going to the other circuit (from the red of the 3 wire) pigtailed though, just not the other wire that is on the same circuit as the black of the 3 wire. This has always been good enough for the last 5 years I've been doing mwbc's. I just find that it is less of a chance of a wire slipping out of the wire nut when I only tie three wires together instead of four. Is this inspector just being difficult?
If you mean that you just extended the neutral by connecting two wires (in and out) to the receptacle, then you are in violation because disconnecting the device from the box will interrupt the downstream neutral.
It sounds like you are doing something a little strange like breaking out the MWBC neutral into individual neutrals at this box and extending just the individual side of the circuit from there to separate outlets. If that is the case, you may be able to argue that it is no longer an MWBC past that point, since interrupting that neutral will not affect the neutral wire serving the other side of the branch. But the inspector could reject that argument.
 
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crtemp

Senior Member
Location
Wa state
If you mean that you just extended the neutral by connecting two wires (in and out) to the receptacle, then you are in violation because disconnecting the device from the box will interrupt the downstream neutral.
It sounds like you are doing something a little strange like breaking out the MWBC neutral into individual neutrals at this box and extending just the individual side of the circuit from there to separate outlets. If that is the case, you may be able to argue that it is no longer an MWBC past that point, since interrupting that neutral will not affect the neutral wire serving the other side of the branch. But the inspector could reject that argument.
Not sure we are on the same page. Here is an example of what I did. I pulled a 12-3 to the refrigerator plug. The black of the 3 wire does the kitchen small appliance circuit and the red does the microhood circuit. The box has the following wires in it. A 12-3 home run. A 12-2 going to the microhood. And a 12-2 continuing on to the next kitchen plug. In the refer plug box I have the neutrals from the 12-3 and the neutral from the 12-2 going to the micro pigtailed down to one wire that gets wired on the plug. The 12-2 that is feeding the other kitchen plugs is not pigtailed all. If the plug gets taken off of the refer it will have no effect on the neutral of the microwave.
 

cadpoint

Senior Member
Location
Durham, NC
I just got tagged for not having all of my neutrals pigtailed down in a plug box.
Pigtailed home individually, right ? Sorry got lost with the following...

...The 12-2 that is feeding the other kitchen plugs is not pigtailed all. If the plug gets taken off of the refer it will have no effect on the neutral of the microwave.
The MWBC neutral will have on it the unbalaced load of what is the diference or a sum difference of each circuit compared to the other circuit - Amp wise.

My thought was this was a Drop the Neutral to a switch box question!
 

crtemp

Senior Member
Location
Wa state
Pigtailed home individually, right ? Sorry got lost with the following...



The MWBC neutral will have on it the unbalaced load of what is the diference or a sum difference of each circuit compared to the other circuit - Amp wise.

My thought was this was a Drop the Neutral to a switch box question!
so am I in violation or not?
 

edward

Senior Member
Not sure we are on the same page. Here is an example of what I did. I pulled a 12-3 to the refrigerator plug. The black of the 3 wire does the kitchen small appliance circuit and the red does the microhood circuit. The box has the following wires in it. A 12-3 home run. A 12-2 going to the microhood. And a 12-2 continuing on to the next kitchen plug. In the refer plug box I have the neutrals from the 12-3 and the neutral from the 12-2 going to the micro pigtailed down to one wire that gets wired on the plug. The 12-2 that is feeding the other kitchen plugs is not pigtailed all. If the plug gets taken off of the refer it will have no effect on the neutral of the microwave.
According to your statement, you are OK. Because when the refer receptacle is removed it will not effect the operation of the circuit.


What did the inspector site you for?
 

crtemp

Senior Member
Location
Wa state
According to your statement, you are OK. Because when the refer receptacle is removed it will not effect the operation of the circuit.


What did the inspector site you for?
He didn't site a code.

Here are is what he wrote

"Multiwire branch circuits shall supply only line-to-neutral loads. Neutrals need to be tied together, all neutrals."

I think it is a BS tag. I know how to wire MWBC's and I always make it so removing the device from the box makes no difference to the neutrals. I hate when inspectors put me in a position of fighting with them because once I do they start tagging me for any little thing (nailplates, etc)

This job is over an hour drive each way for me and I'm sure the inspector will charge me $50 for a trip fee. Do you think it's worth fighting it? I don't understand how an inspector can tag something that is not against code.
 

suemarkp

Senior Member
Location
Kent, WA
Occupation
Engineer
I think he's wrong with both statements. You can supply line to line loads if you use a handle tied breaker (and now you have to), and the neutral has to be installed such that removing a device won't break a shared neutral. WHat you did was compliant. You could try emailing him the code with the details underlines and a drawing of what you did to see if he'll rescind the tag or come out again and green tag it without a trip fee.
 

tortuga

Senior Member
Location
(44.057116, -123.103394)
Occupation
field supervisor
Tell him that the white conductor coming off the outlet is not a neutral.
It is a grounded circuit conductor at that point.
Then the inspector will ask you for a box fill calc on that single gang box :)
 

crtemp

Senior Member
Location
Wa state
I think he's wrong with both statements. You can supply line to line loads if you use a handle tied breaker (and now you have to), and the neutral has to be installed such that removing a device won't break a shared neutral. WHat you did was compliant. You could try emailing him the code with the details underlines and a drawing of what you did to see if he'll rescind the tag or come out again and green tag it without a trip fee.
Yep, used two-pole circuit breakers with handle ties also
 

infinity

Moderator
Staff member
Location
New Jersey
Occupation
Journeyman Electrician
Not sure we are on the same page. Here is an example of what I did. I pulled a 12-3 to the refrigerator plug. The black of the 3 wire does the kitchen small appliance circuit and the red does the microhood circuit. The box has the following wires in it. A 12-3 home run. A 12-2 going to the microhood. And a 12-2 continuing on to the next kitchen plug. In the refer plug box I have the neutrals from the 12-3 and the neutral from the 12-2 going to the micro pigtailed down to one wire that gets wired on the plug. The 12-2 that is feeding the other kitchen plugs is not pigtailed all. If the plug gets taken off of the refer it will have no effect on the neutral of the microwave.
So you have one circuit (from a MWBC) feeding the refrigerator receptacle and a two wire cable continuing on with that same circuit. Those two wires that continue on are landed on the refrigerator receptacle along with the pigtailed neutral and the hot leg for that circuit? That would be code compliant. Personally I would have tailed the 4 neutrals together and the two hot legs as well.
 

mwm1752

Senior Member
Location
Aspen, Colo
Not sure we are on the same page. Here is an example of what I did. I pulled a 12-3 to the refrigerator plug. The black of the 3 wire does the kitchen small appliance circuit and the red does the microhood circuit. The box has the following wires in it. A 12-3 home run. A 12-2 going to the microhood. And a 12-2 continuing on to the next kitchen plug. In the refer plug box I have the neutrals from the 12-3 and the neutral from the 12-2 going to the micro pigtailed down to one wire that gets wired on the plug. The 12-2 that is feeding the other kitchen plugs is not pigtailed all. If the plug gets taken off of the refer it will have no effect on the neutral of the microwave.
Insert your 2 kitchen app circuits in this wiring method -- This would be the only way to do it when using a GFCI receptacles for protection of the down circuit openings
 
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roger

Moderator
Staff member
Location
Fl
Occupation
Electrician
Sounds like this inspector doesn't understand where the MWBC ends and becomes two individual two wire circuits.

Roger
 

kwired

Electron manager
Location
NE Nebraska
I think he's wrong with both statements. You can supply line to line loads if you use a handle tied breaker (and now you have to), and the neutral has to be installed such that removing a device won't break a shared neutral. WHat you did was compliant. You could try emailing him the code with the details underlines and a drawing of what you did to see if he'll rescind the tag or come out again and green tag it without a trip fee.
Though that is what is logical it is not worded properly to interpret that way.

Yep, used two-pole circuit breakers with handle ties also
I'll bet you used either two pole or handle ties, and not both.

Sounds like this inspector doesn't understand where the MWBC ends and becomes two individual two wire circuits.

Roger
Where does it end? Where does it turn into two circuits? AFAIK the entire circuit is a single MWBC, including both "two wire" ends of the circuit.

Again logic says once you separate into the equivalent of two circuits.... but the wording in the NEC doesn't match that logic.

I did not double check NEC before posting so fire away with disagreement, but IIRC this has been debated here before and has been mentioned that if you go strictly by the words in the NEC, the entire MWBC is really supposed to have the neutrals "pigtailed".
 

david luchini

Moderator
Staff member
Location
Connecticut
Occupation
Engineer
Where does it end? Where does it turn into two circuits? AFAIK the entire circuit is a single MWBC, including both "two wire" ends of the circuit.

Again logic says once you separate into the equivalent of two circuits.... but the wording in the NEC doesn't match that logic.

I did not double check NEC before posting so fire away with disagreement, but IIRC this has been debated here before and has been mentioned that if you go strictly by the words in the NEC, the entire MWBC is really supposed to have the neutrals "pigtailed".
Ok, I'll fire away. The NEC definition of MWBC say a branch circuit consisting of two or more ungrounded conductors...and a grounded conductor. The "two wire" ends of the circuit do not comply with that definition, and are therefore not MWBC's.
 

GoldDigger

Moderator
Staff member
Where it splits into multiple circuits. And using that logic everything on the load side of the service equipment would be a MWBC.

Roger
I think that is pushing it a little too far.
After all a Multi Wire Branch Circuit would have to originate at the Branch OCPD. If there are two neutrals leaving the panel, it is not an MWBC, if there is only one neutral leaving the panel, it is and stays that way, since it remains the same circuit even after the wiring is divided in any way.
If we are going to apply the Multiwire designation to a feeder, it would have to be an MWFC. :)
 

mwm1752

Senior Member
Location
Aspen, Colo
IMO the pigtail of the grounded conductor is done to prevent a series current flow with a more than likely humanoid worker in the event of only one of the two energized conductor being turn off with a load on the other one. the OP wiring method clearly eliminates the danger
 
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