Brushed Motor Question.

Discussion in 'General Electronics Chat' started by R!f@@, May 20, 2016.

  1. R!f@@

    Thread Starter AAC Fanatic!

    Apr 2, 2009
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    Motor.png

    I am not that good with some motors hence the question.
    The motor is used in a washing machine. This the same type

    The Armature is fried. The sparking is too much and eats up the brushes.

    The label is in Chinese but googling around I believe it says
    AC 220-240V 50/60Hz 1400rpm
    Wash 4.0A , 50W
    Spin 3.0A, 300W

    I am trying to figure out the stator winding.
    The inductance measured does not add up. I think it may be due to series parallel combination issue. I am not sure. Looking for an expert advice.

    I like to know the two winding details since I think the two power rating is used and the three wires indicate two running conditions. I like to replace the motor and need to know the details to find a compatible motor.

    I have two motors but the wiring is different from outside. I need to take the working ones apart to figure out the stator winding.

    Another problem is the working ones rpm is 12000 ??
    And another one that only says 220-240VAC, 480/17000RPM ??

    I think the second one is two speed one but the rpm is way too high. Don't you think ?
     
  2. Kermit2

    AAC Fanatic!

    Feb 5, 2010
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    Looking at the connections makes me think they have some windings in opposition, or bucking the remaining turns. Weakening the field with the opposite winding would make the motor run faster for the spin cycle.
    You may have to do some disconnect surgery and isolate some wires to figure out the exact winding methodm
     
  3. MaxHeadRoom

    Expert

    Jul 18, 2013
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    An odd ball motor apparently, I would guess that the two power ratings are due to a switching of tapped field windings which are in series with the armature in a Universal motor.
    Typically Universal motors are very high rpm due to the run away condition they operate in, there were once Universal motors used in N.A. machines but did not last long due to the poor rpm control without feedback of some kind.
    Motorola came out with an controller IC aimed especially at this market.
    You may have a problem subbing a replacement, especially if multi speed is needed.
    Max.
     
  4. R!f@@

    Thread Starter AAC Fanatic!

    Apr 2, 2009
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    Could it be the controller is switch from one filed to the other during wash cycle and spin cycle.
    I did repair a few controllers that uses this type motor.
    Odd method though. A triac feeding to a bridge feeding the motor. Seems like that.
     
  5. MaxHeadRoom

    Expert

    Jul 18, 2013
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    That was the Triac/Bridge method used in the TDA1085 IC from moto.
    If you have two different fields then I would guess they are switched for the differnt speeds.
    Max.
     
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  6. R!f@@

    Thread Starter AAC Fanatic!

    Apr 2, 2009
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    Waddaya know.
    You learn something new everyday

    What will happen if I switched to a high speed motor ?
    This motor does have a RPM counter thingy mounted at the back end of the shaft.
     
  7. MaxHeadRoom

    Expert

    Jul 18, 2013
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    Then they may even be using said IC as the method used a coarse tachometer on the motor.
    The rpm may be too high for the wash cycle if just hi speed.
    Max.
     
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