Universal motor wiring

Discussion in 'General Electronics Chat' started by abjay, Apr 1, 2014.

  1. abjay

    Thread Starter New Member

    Mar 14, 2014
    7
    0
    Hi
    I have a 220v universal motor from a washing machine (no other parts) and I want to make a speed controller for it. There are seven connections, two for the brushes, three for the fields and two for the built in tacho. Anyone know the details of how I could make such a controller and the wiring to the motor. I heard references to triacs in this matter and I am keen to learn.
     
  2. MaxHeadRoom

    Expert

    Jul 18, 2013
    10,553
    2,375
    The field is in series with the armature on a Universal motor and the only usual reason for bringing the field out is to reverse the motor, Not sure why you have three wires for the field?
    The IC that was developed for Universal washing machine motors and used a tach feedback was the Motorola TDA1085 IC.
    Max.
     
  3. THE_RB

    AAC Fanatic!

    Feb 11, 2008
    5,435
    1,305
    There are usually two field windings. Which are themselves in series (and in series again with the armature as Max said).

    On some large power tools I have seen a wire tap from the centre of the field windings (between them) which is used to power the brain of the electronic speed controller module.
     
  4. abjay

    Thread Starter New Member

    Mar 14, 2014
    7
    0
    The motor connections are as this link, http://www.youtube.com/watch?v=XrYBAVG5dT4, washer motors are reversible, it would have been handy to have harvested the board from the washer but this was not available to me.
     
  5. Dodgydave

    Distinguished Member

    Jun 22, 2012
    4,998
    745
    They are wired in series like this you may have a tapped field for lower voltages.
     
  6. MaxHeadRoom

    Expert

    Jul 18, 2013
    10,553
    2,375
    In the link you show, the motor was connected in the simple manner of both fields in series with the armature, as is the normal typical configuration and ran at full voltage, so the only thing limiting the maximum rpm is friction and windage. The tach is a simple magnetic sensor disc with typically 8 positions.
    I do have a circuit where a T.M. manuf used the same IC that is used in most of these W.M. motor circuits (TDA1085) in conjunction with a Triac, I can post if you are thinking of building a speed control?
    Also check the data sheet.
    You can control it with a simple triac circuit, but you will not have rpm control.
    A nicer motor is the one used in latest W.M.'s it is called the Fisher & Paykel 3 phase multi-pole motor, these are also popular among the wind generator crowd.
    Max.
     
    Last edited: Apr 2, 2014
  7. abjay

    Thread Starter New Member

    Mar 14, 2014
    7
    0
    If you could post a speed controller and how to connect it would be a great help

    Many Thanks
     
  8. MaxHeadRoom

    Expert

    Jul 18, 2013
    10,553
    2,375
    Here is the one from the T.M.
    Max.
     
    Last edited: Apr 3, 2014
    abjay likes this.
  9. THE_RB

    AAC Fanatic!

    Feb 11, 2008
    5,435
    1,305
    You can buy a speed controller from Harbour Freight complete in a box for about $30 to $40. :)
     
  10. MaxHeadRoom

    Expert

    Jul 18, 2013
    10,553
    2,375
    All depends if you want/need tight RPM control.
    Max.
     
  11. THE_RB

    AAC Fanatic!

    Feb 11, 2008
    5,435
    1,305
    You turn the knob and you get fantastic speed control.

    It all depends if you want good speed:load regulation. ;)
     
  12. MaxHeadRoom

    Expert

    Jul 18, 2013
    10,553
    2,375
    Essentially what I said. :)
    Max.
     
    Last edited: Apr 5, 2014
Loading...