Basic Electrical Diagram

Discussion in 'Electrical Forum discussion & Blog' started by jamz, Oct 17, 2007.

  1. jamz

    jamz New Member

    Messages:
    14
    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)
  2. jwelectric

    jwelectric Electrical Contractor/Instructor

    Messages:
    2,532
    Location:
    North Carolina
    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.
  3. jamz

    jamz New Member

    Messages:
    14
    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.
  4. 480sparky

    480sparky In the Trades

    Messages:
    149
    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.
  5. jwelectric

    jwelectric Electrical Contractor/Instructor

    Messages:
    2,532
    Location:
    North Carolina
    Good thinking.
  6. jamz

    jamz New Member

    Messages:
    14
    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.
    Last edited: Oct 17, 2007
  7. 480sparky

    480sparky In the Trades

    Messages:
    149
    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.
  8. jamz

    jamz New Member

    Messages:
    14
    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?
  9. 480sparky

    480sparky In the Trades

    Messages:
    149
    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.
  10. jadnashua

    jadnashua Retired Defense Industry Engineer xxx

    Messages:
    21,924
    Location:
    New England
    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.
  11. jamz

    jamz New Member

    Messages:
    14
    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?
  12. jwelectric

    jwelectric Electrical Contractor/Instructor

    Messages:
    2,532
    Location:
    North Carolina
    Yes



    .
Similar Threads: Basic Electrical
Forum Title Date
Electrical Forum discussion & Blog Basic electrical questions Aug 30, 2009
Electrical Forum discussion & Blog Basic electric service panel questions Jul 17, 2013
Electrical Forum discussion & Blog switching 15-amp to 20-amp (basic Q's) Sep 26, 2008
Electrical Forum discussion & Blog Basic Wiring Question Aug 6, 2008
Electrical Forum discussion & Blog Circuit Planning Basics Nov 5, 2007

Share This Page