Results 1 to 5 of 5

Thread: puzzler

  1. #1
    brianmiller's Avatar
    brianmiller Guest

    Default puzzler

    While looking at a service equipment panel yesterday, I observed a black lead wire not connected to anything. So I pulled out my voltage sniffer to see if it was live ; it was not.

    However, my sniffer pick up a signal from an equipment ground wire from a different branch circuit (lighting) from the above mentioned black wire.
    I have one of those $15 dollar sniffers so I was thinking I was getting a false signal...

    ...but for the sake of arguement, if I am getting a true voltage/current signal from the equipment ground wire, what would be the causes?

    thanks,

    b

    Similar Threads:
    F.I.R.E. Services

  2. #2
    Join Date
    Mar 2008
    Location
    Charlotte NC
    Posts
    2,303

    Default Re: puzzler

    Quote Originally Posted by brianmiller View Post
    While looking at a service equipment panel yesterday, I observed a black lead wire not connected to anything. So I pulled out my voltage sniffer to see if it was live ; it was not.

    However, my sniffer pick up a signal from an equipment ground wire from a different branch circuit (lighting) from the above mentioned black wire.
    I have one of those $15 dollar sniffers so I was thinking I was getting a false signal...

    ...but for the sake of arguement, if I am getting a true voltage/current signal from the equipment ground wire, what would be the causes?

    thanks,

    b
    You are seeing inductive reactants. Current flowing in a wire next to the ground wire is induced into the ground wire. Very little current but enough to alert the sniffer. The other posibility is a reversed ground neutral connection.

    Sniffers can fool you if that is all you use. i.e. If the power co. has removed power from the house by installing plastic insulators at the meter, your sniffer will indicate the power is on at the panel SEC. The use of a volt meter will show near 0 volts.

    Last edited by Vern Heiler; 09-21-2011 at 09:05 AM. Reason: add other reason
    The beatings will continue until morale has improved. mgt.

  3. #3
    brianmiller's Avatar
    brianmiller Guest

    Default Re: puzzler

    Thanks, Vern.

    So assuming the neutral and ground are not reversed, then there is no concern/ need to mention to homeowner?

    b


  4. #4
    Join Date
    Mar 2008
    Location
    Charlotte NC
    Posts
    2,303

    Default Re: puzzler

    Quote Originally Posted by brianmiller View Post
    Thanks, Vern.

    So assuming the neutral and ground are not reversed, then there is no concern/ need to mention to homeowner?

    b
    No need to mention false reading from sniffer.

    The beatings will continue until morale has improved. mgt.

  5. #5
    James Duffin's Avatar
    James Duffin Guest

    Default Re: puzzler

    I am not a fan of digital volt meters either for the same reason. As long as everything is ok with the circuit they work great. If you get a problem such as a loose connection the meter display can go haywire. I still use a analog meter for most of my troubleshooting.


Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •