1. Computer problem? Tech Support Guy is completely free -- paid for by advertisers and donations. Click here to join today! If you're new to Tech Support Guy, we highly recommend that you visit our Guide for New Members.

diagnose house wiring problem

Discussion in 'Tech Tips and Reviews' started by brhodewalt, Nov 4, 2007.

Thread Status:
Not open for further replies.
Advertisement
  1. brhodewalt

    brhodewalt Thread Starter

    Joined:
    Jun 26, 2007
    Messages:
    0
    All outlets on one circuit are dead. I have located the outlet closest (in the network) to the breaker box. At this outlet (two cables, each with one white, one black and a copper wire), testing with a digital multimeter shows 120V across the black line wire and the copper wire. All other combinations show 0V.

    Two questions:

    1) Am I correct in assuming that the voltage should be across the black and white wires (within one cable), and the lack of this probably points to the problem? (And is the voltage across black and copper normal?)

    2) What problem am I likely seeing?

    Notes:

    I have replaced the breaker and tested for voltage there. I have tested an outlet on another circuit and found 120V across the white/black pair. Nothing obvious changed on the bad circuit before the problem appeared.

    Thanks for any help.

    Bruce
     
  2. JohnWill

    JohnWill Retired Moderator

    Joined:
    Oct 19, 2002
    Messages:
    106,418
    Yep, in truth the copper wire is the ground wire, all the wires are copper. I'm assuming you are talking about the bare copper wire. The ground and the neutral (white) end up going to the same place in the breaker box, and your symptoms indicate the neutral wire is broken between the breaker box and the outlet in question. There should be no switching of the neutral wire on a 110V leg, it should go right to the box.
     
  3. brhodewalt

    brhodewalt Thread Starter

    Joined:
    Jun 26, 2007
    Messages:
    0
    Thanks for your quick reply. Yes, I understand all the wires are copper. By "copper" I meant the bare wire.

    Any idea what my options are for replacing an existing cable in a house built on a slab and with a partial attic?

    Thanks.
     
  4. Elvandil

    Elvandil

    Joined:
    Aug 1, 2003
    Messages:
    51,988
    Wouldn't it be easiest to just find where the while, neutral is broken? The problem has to be betwwen the box and the first outlet. Is it even connected inside the box?
     
  5. JohnWill

    JohnWill Retired Moderator

    Joined:
    Oct 19, 2002
    Messages:
    106,418
    Well, from the description, it sounds like the neutral (white) wire that is broken. I'd STRONGLY suspect that it might just be loose in the breaker box, or loose at the first hop. It's pretty unusual for a wire to suddenly break in a wall unless you're been drilling holes in the walls. :D
     
  6. Elvandil

    Elvandil

    Joined:
    Aug 1, 2003
    Messages:
    51,988
    Exactly. That's why I think a really good look around is appropriate before tearing down any walls and running new wire :D. If it were me, and though contrary to code, I'd short the neutral to the ground in the first box before I'd tear down any walls. It should be perfectly safe if a good connection is made. But I don't think I could sleep until I found the break, especially if any drilling was done and the other conductors may have been compromized.
     
  7. JohnWill

    JohnWill Retired Moderator

    Joined:
    Oct 19, 2002
    Messages:
    106,418
    Yep, when I do wiring here, it is actually to code. Makes me very nervous to see what some people do with electrical wiring! :eek:
     
  8. Skivvywaver

    Skivvywaver

    Joined:
    Mar 18, 2001
    Messages:
    13,951
    Like JohnWill and Elvandil have pretty much said, the problem most likely is either in the box or the first outlet/switch on the run.

    Most of the time it is where the quick connect goes bad. When I wire, I use the lugs on an outlet or a switch and leave the quick connects out of the picture even if I have to pig tail to do it. Quick connects fail. Take the word of a guy that has about 28 years in homes and commercial buildings. Find the first outlet or switch on the run, test for voltage on the "hot side".
     
  9. Elvandil

    Elvandil

    Joined:
    Aug 1, 2003
    Messages:
    51,988
    LOL. I got a call on a cold Winter day from a friend that couldn't get his furnace running. He had it connected by an extension cord running through the living-room, had bypassed the electric eye and all other safety devices, and had pushed the reset button so many times that oil was dripping through the floorboards. No one seemed too concerned--they just wanted it to start.

    Luckily, it didn't start. I told him to call the oil company and went home.

    PS. Not a good friend. I don't seek out idiots or anything :D.
     
  10. JohnWill

    JohnWill Retired Moderator

    Joined:
    Oct 19, 2002
    Messages:
    106,418
    I could tell you some very chilling stories about my first house, involving cheap zip cord plastered into walls, and that was just the tip of the iceberg!

    To get back on topic... brhodewalt, how did you make out checking the wiring and connections on each end?
     
  11. Knotbored

    Knotbored

    Joined:
    Jun 5, 2004
    Messages:
    2,470
    Get a cheap (a dollar or so) continuity tester (battery powered with a light bulb) and as much extra wire as you need to reach both ends of the white wire. Aligattor clip one end-touch the other. If bulb lights the wire has no breaks and problem is at the breaker panel. If the bulb does not llight then white wire is broken (or your cheap continuity tester is broken, so test it .)
     
  12. JohnWill

    JohnWill Retired Moderator

    Joined:
    Oct 19, 2002
    Messages:
    106,418
    Like we said, it's probably at least 95% that just opening the two boxes at either end of the first run that will yield a solution. It's VERY rate for a electrical cable to fail inside the wall without some help.
     
  13. Sponsor

As Seen On
As Seen On...

Welcome to Tech Support Guy!

Are you looking for the solution to your computer problem? Join our site today to ask your question. This site is completely free -- paid for by advertisers and donations.

If you're not already familiar with forums, watch our Welcome Guide to get started.

Join over 733,556 other people just like you!

Thread Status:
Not open for further replies.

Short URL to this thread: https://techguy.org/647835

  1. This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
    By continuing to use this site, you are consenting to our use of cookies.
    Dismiss Notice