Reversing Motor Waste Compactor

Discussion in 'Technical Repair' started by Bargemanmac, Aug 12, 2017.

  1. Bargemanmac

    Thread Starter New Member

    Aug 12, 2017
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    Hi Gents
    I am new to this but thought maybe somebody could help, a friend has an old Pakmaster (UK out of business now) 240 volt kitchen waste compactor.
    it used to drive down the screw with a motor and rubber belt onto pulleys, get to the bottom, compact and the motor would reverse back up to a switch and turn off, there is no switch at the bottom as the height is variable to tell the motor to reverse.
    The problem is it doesnt reverse now just keeps trying to drive down, my question is how does the motor reverse and any ideas what has failed, the only components are basically on/ off switch , program start, top limit switch, bin in position switch, contactor and a relay, i suspect the latter 2 are the problem but would like to know how it works (no wiring diagram) i will try to attach a pic of the relay and contactor.
    Thanks in anticipation
     
  2. AlbertHall

    Distinguished Member

    Jun 4, 2014
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    The datasheet for the contactor shows an accessory overload relay on the last page. Does the compactor include one of these?

    It may be that the method for detecting 'fully compacted' was that the motor current increased with the extra loading.

    If this is the case then maybe whatever sensed the overload is defunct but it also occurs to me that, if the belt slips at the bottom of the movement then the load on the motor will be less than if there was no slip. Does the belt slip or does the motor stall at the bottom?
     
  3. Bargemanmac

    Thread Starter New Member

    Aug 12, 2017
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    Hi , thanks for looking, no the belt doesn’t slip it drives to the bottom and then stalls, did you see the pic ? The relay at the top of the contactor do you think this is an overload sensor ?
     
  4. AlbertHall

    Distinguished Member

    Jun 4, 2014
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    What model is the compactor?
    There may be a wiring diagram somewhere on www.
     
  5. Bargemanmac

    Thread Starter New Member

    Aug 12, 2017
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    Hi mate don’t know the model but it is a Pakmaster now defunct they were in High Wycombe
     
  6. AlbertHall

    Distinguished Member

    Jun 4, 2014
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    Are you absolutely sure that there are no wires going downwards to the bottom of, or underneath, the bin.
     
  7. Bargemanmac

    Thread Starter New Member

    Aug 12, 2017
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    Yep absolutely certain there is only one cable goes half way down to a limit switch that makes when the bin is inserted

    I think I might have to go back up there and make a wiring diagram to get my head round it
     
    Last edited by a moderator: Aug 12, 2017
  8. AlbertHall

    Distinguished Member

    Jun 4, 2014
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    If you can do a wiring diagram that's certainly going to make the guessing game simpler.
     
  9. MaxHeadRoom

    Expert

    Jul 18, 2013
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    I am guessing there is a current relay in the motor circuit that operates the reverser when the load appears on the motor.
    From the picture it appears to be a rigged up model, maybe why there is no schematic!
    Max.
     
  10. #12

    Expert

    Nov 30, 2010
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    This is what I have. Maybe it will get you started.
     
  11. MaxHeadRoom

    Expert

    Jul 18, 2013
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    It appears to show a centrifugal detector switch as opposed to a current detector!
    Max.
     
  12. AlbertHall

    Distinguished Member

    Jun 4, 2014
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    But the reversing is controlled by 'limit switch B section'.
     
  13. MaxHeadRoom

    Expert

    Jul 18, 2013
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    So what is the centrifugal switch shown mounted on the top of the motor for?
    Max.
     
  14. JWHassler

    Member

    Sep 25, 2013
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    Centrifugal switch is for starting - in either direction
     
  15. MaxHeadRoom

    Expert

    Jul 18, 2013
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    Never seen a cap start centrifugal switch mounted to the back of a motor?
    http://www.searspartsdirect.com//re...-centrifugal-switch-in-a-trash-compactor.html
    Quote: "This repair guide shows how to replace the motor centrifugal switch in a trash compactor. The motor centrifugal switch, which is on top of the drive motor, controls which direct in which the drive motor turns. If the ram travels down but won’t return to the top, replace the motor centrifugal switch"
    Max.
     
    Last edited: Aug 12, 2017
  16. Bargemanmac

    Thread Starter New Member

    Aug 12, 2017
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    I didn’t look at the motor to see if there is a Centrifugal Switch, next time I go up there I will check, thanks for the help so far , I will report back
     
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