Results 1 to 7 of 7
  1. #1
    Join Date
    Mar 2008
    Location
    England
    Age
    34
    Posts
    63
    Rep Power
    17

    Testing with a Megger



    Hi Guys,

    I've been told a few different ways to do this by the blokes I work with.

    Can anyone confirm to me though the correct and safe way to test single and three phase motors using a megger. Either balance testing (which I believe is using the ohms setting) or insulation testing (using the volts setting).

    Many thanks in advance,

    Bash



  2. #2
    Join Date
    Jun 2011
    Location
    Australia
    Age
    44
    Posts
    337
    Rep Power
    21

    Re: Testing with a Megger

    To megger test a 3-phase motor with a 1000volt megger tester:

    Testing to earth

    a) Switch off the circuit breaker.

    b) Connect black megger test probe to earth. Check for ground continuity, to a terminal box bolt (this is check for good ground connection)

    c) With black probe still connected to ground, connect the red test probe to a motor terminal. Push test button. Insulation resistance should indicate 1 meg-ohm or more.

    d) Repeat test on remaining motor terminals

    Testing between windings

    e) Disconnect all line connections & remove bridging links.

    f) Identify the individual winings

    g) Connect black probe to one winding, test with red probe to other windings. Again, insulation resistance should indicate 1 meg-ohm or more.

  3. #3
    Join Date
    Oct 2007
    Location
    manchester
    Age
    50
    Posts
    5,707
    Rep Power
    45

    Re: Testing with a Megger

    g- ur only testing resistance so the reading will be in ohms- in 3 phase they should be equal in a single phase compressor they will be different according to start and run windings

  4. #4
    Join Date
    Sep 2003
    Location
    ISRAEL
    Age
    72
    Posts
    4,266
    Rep Power
    46

    Re: Testing with a Megger

    An important note, never ever megger a compressor when it is under vacuum!!

  5. #5
    Join Date
    Oct 2012
    Location
    Russia
    Age
    42
    Posts
    392
    Rep Power
    18

    Re: Testing with a Megger

    That can happen?

  6. #6
    Join Date
    Oct 2007
    Location
    manchester
    Age
    50
    Posts
    5,707
    Rep Power
    45

  7. #7
    Join Date
    Sep 2007
    Location
    Split Croatia
    Age
    57
    Posts
    6,175
    Blog Entries
    6
    Rep Power
    36

Posting Permissions

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