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jamz
10-17-2007, 10:21 AM
Ive been reading alot here about running Light Switch Outlets separate from Recept Outlets.
After speaking to a former inspector for my area, he agrees with all of you but also added that he likes to see new service for an area of the home to be brought to a J-Box as close to the area as possible. Then branch off to where needed. This is based on the conversation about my basement remodel where i will be installing a suspended ceiling grid panel system and it would be easier to access. He said it would look cleaner and more professional that way. I think I understand so I did a diagram. Is this what he is referring to.......

http://home.comcast.net/~swingjamz/basic_elec.JPG

And, what is everyones take on this? What makes for a cleaner installation for you?

JAmZ (Chicago,IL)

jwelectric
10-17-2007, 10:49 AM
Don't switch the white wire in the switch but instead let it be spliced under a wire nut.

I personally wouldn't use the junction box necessarily. If I could access another box such as the switch or one of the receptacles it would be that many less joints for something to wrong.

jamz
10-17-2007, 11:10 AM
Don't switch the white wire in the switch but instead let it be spliced under a wire nut.

I personally wouldn't use the junction box necessarily. If I could access another box such as the switch or one of the receptacles it would be that many less joints for something to wrong.

Your absolutely correct. Not sure why I showed it that way. Been a long day :( (revised drawing)

So, you would go directly into the switch box then branch out there? I could understand this as the box would be standing height accessable as opposed to a recept access down low.

480sparky
10-17-2007, 11:39 AM
The only problem with doing this is the current requirement to use AFCI protection in bedrooms (which will expand to all 15- and 20-amp 120v circuits when the 2008 is adopted). AFCI breakers won't work in mulit-wire branch circuits.

So if AFCI protection is required, youre best option is to use two 14/2 runs, one for the lights and the other for the receps. However, in all my years of wiring, it's an extremely rare case that having the lights and receps seperated is of any advantage.

jwelectric
10-17-2007, 11:44 AM
Your absolutely correct. Not sure why I showed it that way. Been a long day :( (revised drawing)

So, you would go directly into the switch box then branch out there? I could understand this as the box would be standing height accessable as opposed to a recept access down low.
Good thinking.

jamz
10-17-2007, 12:24 PM
The only problem with doing this is the current requirement to use AFCI protection in bedrooms (which will expand to all 15- and 20-amp 120v circuits when the 2008 is adopted). AFCI breakers won't work in mulit-wire branch circuits.

So if AFCI protection is required, youre best option is to use two 14/2 runs, one for the lights and the other for the receps. However, in all my years of wiring, it's an extremely rare case that having the lights and receps seperated is of any advantage.

Ok, now im confused. Could you explain multi-wire branch circuit? In my drawing, im showing 2 separate 15a Single Pole CB's carrying 110v each. Yet they do share the same neutral. Is this a branch circuit or did I just show a 220v line? The Hots never meet. OMG....This is exactly why I'll have an electrician :D . But one is never to old to ask questions and learn.

BTW this is not a bedroom run. Just basic wiring (20 feet from panel) for Family Room lighting and recept.

480sparky
10-17-2007, 12:43 PM
Ok, now im confused. Could you explain multi-wire branch circuit? In my drawing, im showing 2 separate 15a Single Pole CB's carrying 110v each. Yet they do share the same neutral. Is this a branch circuit or did I just show a 220v line? The Hots never meet. OMG....This is exactly why I'll have an electrician :D . But one is never to old to ask questions and learn.

BTW this is not a bedroom run. Just basic wiring (20 feet from panel) for Family Room lighting and recept.

A Multi-Wire Branch Circuit is, by definition, exactly what you have, two hots sharing a commong neutral. If you ran two 14/2s instead, you would have two branch circuits.
Nothing inherently wrong with MWBC's, but with the 2008 NEC coming out, all residential 15- and 20-amp 120v circuits must have AFCI protection, and AFCI's won't work on MWBCs. But that's down the road... don't worry about it.

jamz
10-17-2007, 12:54 PM
Thanks for the clarification. I'm plan on a separate run for a bathroom that will contain a GFI. Do GFI's work under MWBC's?

480sparky
10-17-2007, 01:46 PM
Depends on where you're installing the GFI, as a breaker in the panel or as a device at the point of use.

A two-pole GFI breaker will work on a MWBC. But two single-pole GFI breakers cannot share a common neutral.

If you are installing a GFI device, then it must be installed after the two circuits are separated. In your drawing, the recep could be a GFI outlet with no problem.

jadnashua
10-17-2007, 04:11 PM
A GFCI senses the hot and neutral power flow. If there is a difference, it trips since the only place it could go is either through you or something else to ground.

jamz
10-17-2007, 07:12 PM
Do the new AFCI breakers contain both GFI and AFCI sensing circuitry? If so, would I still need a GFCI near a water source if the circuit is already protected by AFCI at the panel?

jwelectric
10-17-2007, 08:13 PM
Do the new AFCI breakers contain both GFI and AFCI sensing circuitry? If so, would I still need a GFCI near a water source if the circuit is already protected by AFCI at the panel?

Yes



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