Shared neutrals...

[sparkyrick]

How many of you share your neutrals with lighting and receptacle loads in commercial jobs and how many don't?

 

[iwire]

I run multiwire branch circuits anytime it is practicable.

As most times my lighting is 277 I don't often have a choice to place receptacles and lights on the same multiwire branch circuits.

 

[roger]

I plan my projects with as many MWBC's as I can regardless of the system voltage.

Roger

 

[hardworkingstiff]

I use MWBC's also. They are more efficient cost less.

 

[sparkyrick]

I use MWBC's also. They are more efficient cost less.

So in your MWBC's, I take it you share neutrals with lighting and receptacles then?

 

[roger]

So in your MWBC's, I take it you share neutrals with lighting and receptacles then?

Not trying to answer for Hardworkingstiff, but unless there was some special circumstances there would be no reason not to if the lighting was 120v.

Roger

 

[iwire]

And I would as well if it circumstances allowed. :smile:

 

[infinity]

I use MWBC's whenever possible. That would include lighting and receptacles if the voltage was only 208Y/120.

 

[George Stolz]

I think I just found something to add to the FAQ.

Do a search for "shared neutrals" and you'll hit pay-dirt.

Check out my favorite related thread, with 145 replies.

 

[tallgirl]

The only commercial work I've done was a "Just replace whatever was there before" job and it had shared neutrals like nobody's business. At first they looked weird. Now whenever I think I'd like more than 1 20A circuit to go somewhere, I think a MWBC might be a nice idea.

 

[LarryFine]

Julie, I agree. MWBC's are electrically (voltage drop, etc.) and mechanically (labor and KO usage) more efficient. The concern expressed is that MWBC's should be all-receptacle or all-lighting, and not mixed.

Theoretically it should not matter, but if practical, I like keeping them separate for performance's sake, phase count aside. While lighting can also affect lighting, it seems that receptacle loads "shouldn't" affect lighting.

The biggest concern for MWBC's is that it's the one configuration where a poor connection in the neutral pathway can result in over-voltage problems on adjoining circuits. Added: Besides, my mom taught me to share.

 

[kbsparky]

All services have what is termed a "shared neutral"

What's good for the goose is good for the gander .... :grin: