Correct grounding of metal junction box w/splices for 3 circuits

[Cookie]

Hmm, I didn't get a reply notification; anyway



How could a neutral be anything but dead when it's grounded at the panel?

Open a neutral under load, and it will float up to 120 volts.

 

[Noah Katz]

@davesparks Solid points, thanks very much for taking the time to explain.

@Cookie Hmm, yes it will if it gets disconnected at the ground end; another good point, thanks.

 

[davesparks]

Open a neutral under load, and it will float up to 120 volts.

Yes, normally that would happen on the load side of the break.
However the proposed situation of joining three neutrals together would prevent the voltage rise from occurring, but it would overload the other two neutrals.

 

[Cookie]

Yes, normally that would happen on the load side of the break.
However the proposed situation of joining three neutrals together would prevent the voltage rise from occurring, but it would overload the other two neutrals.

Yup, that is unless someone shut down the microwave circuit un-doing the wire nuts thinking they are all dead. This is why the NEC requires any branch circuit sharing a neutral be equipped with listed handle ties or a multi pole breaker.

 

[Cookie]

Here is a good read on why MWBC need handle ties:

Independent Electrical Contractors

IEC is a trade association representing more than 3,300 members with 50 chapters nationwide.

www.ieci.org