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Help 3ph motor

  1. Aug 4, 2006 #1


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    I have just replaced an inverter driven 3ph motor and wired it the same as the old one, it runs (cogs) backwards and is noisy.

    The motor is 230 v 3ph, it has 6 wires, yellow, black, white, violet, blue and brown.
    testing with ohm meter i have 45 ohms between yellow- black, white-violet
    and blue- brown.
    so i connected as yellow- white, violet- brown, blue- black, this should give me a delta circuit, testing on volts the readings are equal between the three terminals, what is wrong???
  2. jcsd
  3. Aug 5, 2006 #2


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    I think all you need to do is switch two phases to reverse the direction of rotation.

  4. Aug 5, 2006 #3


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    I havn't played with one of those since school.
    IIRC getting the colors backward will cause problems like that. I think the high side colors are black, violet, and blue. Since you seem to be using yellow, white, and blue then running backward and cogging sounds about right.

    School was a really long time ago
  5. Aug 12, 2006 #4
    Motor data plate

    Please supply more data plate information. In most industrial applications a six lead three phase motor is one of the following:
    1.) Star Delta start (two or three contactors needed depending if it is open or closed transistion)
    2.) Part winding start (two contactors needed)
    3.) Two speed motor (three contactors needed)
  6. Aug 12, 2006 #5

    For a Star Delta start you need three contactors for open transition and four contactors for closed transistion. While I doubt you have this type of motor because of the ohms you measured it could be a two speed motor.:frown:
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