Results 1 to 4 of 4

Thread: Testing for absence of voltage on MCHL cable

  1. #1
    Join Date
    Mar 2014
    Location
    Alaska
    Posts
    5

    Testing for absence of voltage on MCHL cable

    We are getting ready to start a demolition project in a mine, that we have to demo out cables with voltages ranging from 4160 to 120V. The drawings are sketchy to non-existent. Is there a tool that we can run over the MCHL cables that could tell us if the cable is de-energized and safe to cut. There is no drawings that show what cables are in what trays and this will just be weeks and weeks of tracing cables out. Does anyone have any ideas for tools or procedures we can use prior to cutting into the trays and cables to verify a safe working condition. Thanks

  2. #2
    Join Date
    Jul 2006
    Location
    San Francisco, CA, USA
    Posts
    6,950
    Hmmm... something I would stake my LIFE on? No.

    There are these for MV cables, which will only be useful if NONE of the cables are energized:
    http://www.davis.com/Product/HD_Elec...UaAqLXEALw_wcB
    But they can't be used for anything under 2400V L-G and if there is a bundle of cables, it will not tell you WHICH one has a field around it. If it were me, I would ONLY start at one end and remove it, then use voltage meters to find the other end and remove it, then take out the KNOWN cable in verifiable chunks, even if it boils down to line of sight, no matter how long it took.
    __________________________________________________ ____________________________
    Many people are shocked when they discover I am not a good electrician...

  3. #3
    Join Date
    Nov 2004
    Location
    Northern Virginia
    Posts
    1,011
    Quote Originally Posted by Pete27696 View Post
    We are getting ready to start a demolition project in a mine, that we have to demo out cables with voltages ranging from 4160 to 120V. The drawings are sketchy to non-existent. Is there a tool that we can run over the MCHL cables that could tell us if the cable is de-energized and safe to cut. There is no drawings that show what cables are in what trays and this will just be weeks and weeks of tracing cables out. Does anyone have any ideas for tools or procedures we can use prior to cutting into the trays and cables to verify a safe working condition. Thanks
    Standard procedure for MV cables is to spike them remotely.

    http://www.mitchellinstrument.com/hy...awg-cable.html

    Mark

  4. #4
    Join Date
    Mar 2003
    Location
    Perry, Mi. Shiawassee
    Posts
    66
    Quote Originally Posted by Jraef View Post
    Hmmm... something I would stake my LIFE on? No.

    start at one end and remove it, then use voltage meters to find the other end and remove it, then take out the KNOWN cable in verifiable chunks, even if it boils down to line of sight, no matter how long it took.
    start at one end, hand over hand remove the wire from the cable tray before you cut out that section and proceed, hand over hand until you reach the other end.
    or shut down and lock out all supply and whack away.
    jerryalan

Posting Permissions

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