Question about using common trip on two isolated circuits

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Greetings, I have been a licensed electrician for quite a long time (79 to be exact). My understanding of common trip breakers are to protect 220 volt circuits. I had an inspector this week turn down a new service because I did not use common trip breakers for two circuits sharing the same neutral. I fed back to the original panel for 12 circuits with 6 neutrals, and balanced the load on the new breakers accordingly, no ACFI or GFCI circuits in the mix. He said that either every circuit HAD to have their own neutral, or I had to put common trip breakers in place for these two circuits.

Is this a new code, or a misunderstanding by the inspector? I obviously can buy the Quad double common trip set up breakers to get around this infraction... beings adding 6 more neutrals will almost be impossible in the existing conduit, but I would rather know if he is making something up; or I have missed a code that I should have known. Granted, being in the business for some 35+ years, I have seen a lot of code changes... some I have been on top of; some slip by. I am not an argumentive person and would never argue with an inspector unless I felt I was right and never wanted to work in that city again! I have a problem with a common trip on what used to be an acceptable 3 wire dual circuit.

Thank you. Randy W
 

iwire

Moderator
Staff member
Location
Massachusetts
Randy, a few code cycles ago the rules changed and now require a disconnecting means at the panel that will switch both hots off that share a neutral.

How you do that is up to you, a common trip two pole breaker is one way, another is two single poles with a handle tie from that breaker maker.
 

infinity

Moderator
Staff member
Location
New Jersey
Occupation
Journeyman Electrician
As Bob stated just get the proper handle ties an install them, problem solved.

Welcome to the Forum. :)
 

templdl

Senior Member
Location
Wisconsin
As Bob stated just get the proper handle ties an install them, problem solved.

Welcome to the Forum. :)

Ditto. A common trip breaker would do the job should you not have a handle tie available or not take the time to get one. The issue with common trip breakers is in the rare event that one of the shared branches trips it will take out the other which often proves to be a nuisance. (2)1p breakers tied together with an inexpensive handle tie is preferable as if one pole trips it would not open the other and handle ties don't take much room to stock either.
 

Little Bill

Moderator
Staff member
Location
Tennessee NEC:2017
Occupation
Semi-Retired Electrician
Article 210.4(B) just says MWBC require a means to DISCONNECT both circuits at the same time. That is just for manual disconnecting, it doesn't say they must "trip" at the same time.

(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.
 

kwired

Electron manager
Location
NE Nebraska
Ditto. A common trip breaker would do the job should you not have a handle tie available or not take the time to get one. The issue with common trip breakers is in the rare event that one of the shared branches trips it will take out the other which often proves to be a nuisance. (2)1p breakers tied together with an inexpensive handle tie is preferable as if one pole trips it would not open the other and handle ties don't take much room to stock either.
Additional comments I have to add to this:

Handle ties allow for independent tripping - but to reset just one often means you will end up opening the contacts in the other during the process.

Two single pole breakers plus a handle tie often cost about the same as a two pole breaker.

Three single pole breakers plus a three pole handle tie kit is likely much less then a three pole breaker though.

Use you own discretion which method you decide to use.
 

jap

Senior Member
Occupation
Electrician
Randy, a few code cycles ago the rules changed and now require a disconnecting means at the panel that will switch both hots off that share a neutral.

How you do that is up to you, a common trip two pole breaker is one way, another is two single poles with a handle tie from that breaker maker.


If I was involve in any sort of breaker manufacturing I'd use your last 2 words of this post as my CB handle...... That' s pretty catchy.


JAP>
 

jap

Senior Member
Occupation
Electrician
If I was involve in any sort of breaker manufacturing I'd use your last 2 words of this post as my CB handle...... That' s pretty catchy.


JAP>

Don't confuse "CB Handle" to mean circuit breaker handle,,,,,, I was referring to citizens band........ 10-4 good buddies ......:)
 
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