Using a PLC to contorl/simulate the use of a washing machine

[pablome]

washing machine plc

I was wondering if its possible to take apart the washing machine and have the motor, buttons or whatever else controlled by the plc as a project.
If there is a controller ill just replace it with the PLC.
I wont keep the tub and agitator, just want to control like valves, or a pump, the motor.
However I want to figure out or get suggestions on how to control the motor if im just gotta use a digital In/Out PLC....using thresholds or how?

 

[FvM]

plc washing machine

There's no easy answer without knowing the motor type and control method. To achieve the speed range from washing to spin-drying, most machines of a variable speed drive, either a DC motor with tachometer feedback or a threephase AC-motor with an electronic inverter. If the motor control is a separate unit, it's possibly controlled by digital signals (e.g. contact closure). Recent machines can be expected to have the motor control functions integrated in a single board electronic controller.

The best oportunities for your project are in using a machine with an electromechanical controller, that can be replaced by a PLC with digital IOs only. You should have a schematic diagram of the machines electrical circuit as a first step.

 

[pablome]

plc for washing machine

Thankyou. So you mention my best bet is using a electromechanical controller of a washing machine? Are these difficult to find? (I wont buy a brand new one off course.)

 

[venix]

plc lwashing machine

Hello!

You can use a motor with inter-changeable(induction motor) poles to change the speed betwen 2 thresholds(or 3).This types of motors are suitable for cranes.
Or you can use an induction motor drived by an inverter (you need for the PLC an analog output 0-10 V or 0(4)-20 mA to control the speed of the motor or some communication capabilities(Profibus,Industrial ethernet...) but for a washing machine I don't think they are necesary).

Or other types of motors controlled by a drive with an analogical input for controling the speed.

Best regards!
venix