changing an ac single phase motor direction

Discussion in 'The Projects Forum' started by amandpm, Oct 14, 2017.

  1. amandpm

    Thread Starter Member

    Aug 20, 2007
    23
    0
    I have a very old Masters AC single phase 3hp motor that will run on 115v or 230v each hooked up the same way.
    The motor runs clockwise and there is no indication on the tag if it can run CCW.
    There are only 4 wires coming out of the motor Black, Gray, Yellow, Red.
    Yellow and Red are tied together for both 115v and 230v. while Black and Gray are hooked up to the power source along with a Green wire that is secured to a screw and does not come out from the inside of the motor.
    Question is Can I swap either black or gray with either yellow or red to have the motor run CCW?
    Master alternating current motor
    serial CX 205
    Style 252876
    Type RA
    RPM 1725
    Code C
    Frame 213
    HP 3
    This is on the tag and I can't seem to find any information about this motor Thanks in advance.
     
  2. MaxHeadRoom

    Expert

    Jul 18, 2013
    17,768
    5,405
    It sounds like you have both windings exiting the motor, if so just reversing one of them should give you the reverse you need.
    How is it possible to hook the motor up the same way for either voltage does not sound right?
    Where is the capacitor connected?
    Max.
     
  3. amandpm

    Thread Starter Member

    Aug 20, 2007
    23
    0
    Max this motor has to be over 50 years old, it is totally enclosed and the wires coming out of the motor are the real old fabric covered kind but yea I was also stunned to see the diagram and the same hook up for 115 & 230, there is no visible capacitors on the outside of the motor, I am thinking maybe there is none inside as well but I have one nut out of 4 that spins the bolt that holds the front cover on that is holding me back from taking off the cover.
    There isn't to much information on these motors on the net that I can find.
     
  4. MaxHeadRoom

    Expert

    Jul 18, 2013
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    Can you post a picture?
    Max.
     
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  5. Ramussons

    Well-Known Member

    May 3, 2013
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    Are you sure? 115 or 230 without any change?
     
  6. amandpm

    Thread Starter Member

    Aug 20, 2007
    23
    0
    Update--> I was wrong about the 115v & 230v being hooked up the same as I found out by taking a picture and looking at the picture which shows they are different hookups, my eyes didn't catch it but the camera did.
    3 hp motor pictures 003.jpg
     
  7. amandpm

    Thread Starter Member

    Aug 20, 2007
    23
    0
    couple pictures 3 hp motor pictures 006.jpg 3 hp motor pictures 008.jpg 3 hp motor pictures 009.jpg 3 hp motor pictures 010.jpg
     
  8. MaxHeadRoom

    Expert

    Jul 18, 2013
    17,768
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    No Capacitor?
    What is the word before 'Current Motor' at the top of the plate?
    Max.
     
  9. MaxHeadRoom

    Expert

    Jul 18, 2013
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    The fact it is over fifty years old and if not fitted with a capacitor,I'm guessing it is it will be a Repulsion-Induction motor with brushes and a commutator.
    Max.
     
  10. amandpm

    Thread Starter Member

    Aug 20, 2007
    23
    0
    Max, Sorry about my ignorance, does that mean I can not change the direction to CCW ?
    Yellow and Red are tied together now separate from any power source which is the 230V hook up.
    115v would be Black and yellow tied to power source along with Gray and Red utilizing all 4 wires.
     
  11. MaxHeadRoom

    Expert

    Jul 18, 2013
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    Measure the resistance between all 4 conductors.
    Max.
     
  12. amandpm

    Thread Starter Member

    Aug 20, 2007
    23
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  13. MaxHeadRoom

    Expert

    Jul 18, 2013
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    OK it looks like it is just either series or parallel for two winding's, so I would think transposing one of the windings, either B & R or G & Y should reverse.
    Max.
     
  14. amandpm

    Thread Starter Member

    Aug 20, 2007
    23
    0
    I just tried B & Y to the power source and it ran CW with the G & R tied together separate from the power source
    So then I tried G & R to the power source, the same thing ran CW with the B & Y tied together separate from the power source.
    Any other options to try?
     
  15. MaxHeadRoom

    Expert

    Jul 18, 2013
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    I recall now that if the motor is a repulsion-induction motor as it appears to be, unfortunately I believe the only way to reverse it is to move the position of the brushes, whether it has this feature is not obvious without opening it up.
    When it runs or you turn it by hand can you detect the sound of brushes on a commutator?
    Max.
     
  16. amandpm

    Thread Starter Member

    Aug 20, 2007
    23
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    I go outside and try to manually turn the shaft and listen.
    From what I understand that company stopped in 1963 so it could maybe be 60+ yrs old, and I have one nut on the face that spins, taking it apart could be a task.
     
  17. MaxHeadRoom

    Expert

    Jul 18, 2013
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    Repulsion motors fell out of favour soon after that date.
    Max.
     
  18. amandpm

    Thread Starter Member

    Aug 20, 2007
    23
    0
    Sorry about the huge delay, I was working on another motor and compressor that is a 5hp that is up and running.
    I did manage to take it apart and found out that I had to start at the rear or back of the motor by taking out the 4 screws on the back butt cap by doing this and taking off the cap I found out why the front cap bolt was just spinning ( because the long bolts were not secure to the frame aka welded etc which allowed the front cap bolts to spin.) so after taking off the back cap I was able to access the long bolts that were spinning so then I took out the long bolts and was able to take off the front cap as well.
    So in the rear/back there is the cap with a recessed area for the bearing then there is a "Plate" with 4 stationary brushes equally separated from each other BRUSHES WITH WIRE AND CONNECTED IN PAIRS, NO TERMINALS > .28" x .87" x 1.38" Brush 321P
    that a spring type coiled thin metal wire keeps constant pressure forcing them down onto a pure copper segmented deal formed around the shaft.
    I cleaned up that copper deal and it is in good shape and I repaired one of the copper wires that was attached to the carbon brushes that was frayed and wrapped around that frayed section pure silver super thin wire and some solder joints to keep it in place.
    With the shaft unit completely out of the housing, I pulled off the front and back bearings ( 6205 NSE) and cleaned us some slight surface rust on the angled steel bars that are about 4 inches long and 3/8" wide, those are angled along with the inside of the housing metal fixtures.
    This is where I am at now if you require pictures I can take them for a visual.
    One thing for sure I like this old motor design way better than the 5hp farm duty motor I took apart, the quality imo was much better along with the beefy cast iron components.
     
  19. MaxHeadRoom

    Expert

    Jul 18, 2013
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    I will have to pull my old notes out as it has been a long time, but there are about 3 versions of the reluctance motor but usually the brushes have to be rotate to a different position relative to the stator.
    Does it look as though there is a means of moving them radially to another position?
    Max.
     
  20. amandpm

    Thread Starter Member

    Aug 20, 2007
    23
    0
    I don't think there is a way of moving them as to make a difference as they are separated equally apart.
    I include a photo of the plate that has the brushes mounted and the position it is in the motor, notice in the picture I have written "Motor top" and positioned the plate with the brushes as it came out of the motor. motor brushes 007.jpg
     
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