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

 

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?

 

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 ?

 

What model is the compactor?
There may be a wiring diagram somewhere on www.

 

What model is the compactor?
There may be a wiring diagram somewhere on www.

Hi mate don’t know the model but it is a Pakmaster now defunct they were in High Wycombe

 

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

 

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

 

If you can do a wiring diagram that's certainly going to make the guessing game simpler.

 

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.

 

This is what I have. Maybe it will get you started.

 

It appears to show a centrifugal detector switch as opposed to a current detector!
Max.

 

It appears to show a centrifugal detector switch as opposed to a current detector!
Max.

But the reversing is controlled by 'limit switch B section'.

 

But the reversing is controlled by 'limit switch B section'.

So what is the centrifugal switch shown mounted on the top of the motor for?
Max.

 

Centrifugal switch is for starting - in either direction

 

Centrifugal switch is for starting - in either direction

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.

 

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.

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

 

Hi there,
I personally used to manufacture these between 2001 and 2007, Sheet metal work fabrication and then the installation of the electrics. The business folded shortly after i left. A Random search for an old machine (Too show the kids) brought me here. The Circuit is very simple, Reversing the polarity of the "Start" winding, in relationship to the "Run" winding, reverses the direction of rotation. The motor does indeed have a centrifugal switch, the Ram is driven down, via a drive belt and central drive shaft, through the Green Nylon nut attached to the top-plate and Ram plate. When the motor stalls it reverses direction and the travel is stopped by mean of the micro limit switch mounted on the chassis. 11 years on i have very limited memory of the actual circuit but other than the contactor or relay failing, your likely Fix is to look at the centrifugal switch. To be fair if a motor failed, we would always just replace it, I believe i did however goto site and repair one, but my memory is very hazy 11 years on.