Batch Plant Loading


Thread Starter

Yuzna, Ray

I am having trouble figuring out this wagon loading process. Heres the problem: Bulk material is to be loaded into a wagon from a bin via a
conveyor belt. The control sequence is enabled by using a basic stop/start station. The loading process is carried out as follows once the control sequence has been enabled.

Conveyor belt:
The conveyor belt is started via motor contactor K1 when a wagon is in the loading position(limit switch S3 is actuated). The conveyor belt is stopped when the wagon has left the loading position and the next wagon to be filled has not reached the loading position within 20 seconds.
The bin's discharge valve:
Discharge valve Y1 is opened when the belt drive is on and an empty wagon is ready for loading. The discharge valve is closed when the weight set on weight scale B1 has been reached. The commands for opening and closing of the valve may be applied only until the discharge valve has
reached the new position.
Locking pawl:
Locking pawl Y2 is not opened until 10 seconds after the "Full" signal to enable the material that is still on the conveyor belt to be
loaded into the wagon. The locking pawl is closed again immediately when the full wagon has left the loading position. i.e. when limit
switch S3's contact reopens.

When the next wagon reaches the loading position, the procedure is repeated until stop button is pressed.

Johan Bengtsson

I fail to understand what your question is.
Is your problem about how to write a PLC program for this?
or is it something else?

/Johan Bengtsson

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