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Help wiring AC motor

  1. Sep 22, 2012 #1
    I hope someone can help me.
    I have an old 30 HP motor that I need to get working...if possible.
    It is a 12 wire Toshiba, dual voltage. 230V 460V.
    To wire for the low voltage the nameplate says:
    connect wires 4,8,10 and 2 to supply 1.
    Wires 9,5,11 and 3 to supply 2 and
    Wires 6,7,12 and 1 to supply 3.

    Someone has cut the wires and removed some of the numbers. The only identifyible numbers are 4,9,6,8,5 and 7.
    Wires 1,2,3,10,11 and 12 have no numbers.

    I have an electronic multimeter with resistance measurements.
    Is there any way I can check resistances between what I know and what I need to know to identify the remaining wire numbers?

    FYI: for high voltage hook-up the wires are paired:
    6 and 9.
    4 and 7.
    8 and 5.
    10,2 and L1.
    11,3 and L2 and
    12,1 and L3.

    I appreciate any help.
  2. jcsd
  3. Sep 22, 2012 #2


    User Avatar
    Gold Member

    Your 12 leads are for 6 identical coils paired up as
    1 , 4
    2 , 5
    3 , 6
    7 ,10
    8 , 11
    9 , 12
    as long as you have 1 side of each coil you can do a simple continuity check to determine the other side and corresponding number. It seems you are in luck.
    You have 4 , 5 , 6 , 7 , 8 , 9
    if you disconnect all wires from each other, you should check for continuity to the case, If you have none, you can proceed to pair 4 to 1 , 5 to 2, 6 to 3, 7 to 10, 8 to 11, and 9 to 12.

    If it were me,once you have them all numbered I would hook it up to a starter and properly size the OLs. If it appears to run fine then I would check for balanced current in each leg.
    If they are reasonably balanced you should be ok.
  4. Sep 22, 2012 #3
    Thanks for reply, will go and check what you say right now.
    I am normally not that lucky, maybe I should buy a lottery ticket tonight!
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