Exercises for Conveyor

Write a PLC Program for the Packaging Machine. You will find the description of operation of the machine below. Test your program with a simulation tools.

Packaging Machine should make a stack of 7 boxes at the end of the conveyor and move the stack to the warehouse, which is below the stacker (downstairs).

The conveyor starts by pressing the Start-Button (I0.0) after 3 seconds delay. The Start-Button also activates automatic mode. Machine will be stopped by pressing the Stop-Button (I0.1). The conveyor M1 moves the box to the end of the conveyor, when sensor S2 (I1.2) detects it. The Pneumatic Cylinder Y1 (Q1.1) pushes the box to the ramp and the box drops to the stacker. The cylinder has limit switches in both ends S4 (I1.3) and S5 (I1.4). The stacker moves up and down with Electric Motor M2 (Up: Q1.2; Down: Q1.3). The stacker has an upper level sensor S6 (I1.5) and lower level sensor S7 (I1.6). The initial position of the stacker is Up.

Sensor S3 (I1.2) detects that the box is on the stacker and the stacker can be moved one step lower to wait another box. The stacker can receive maximum 7 boxes. After 7th box the stacker will remove the boxes in the warehouse (downstairs). During the removal process other actions of the machine should be stopped and the signal lamp should blink red light (H2: Q0.1) with 1 Hz frequency as an alert. Also warning horn/buzzer H3 (Q0.2) should be on and automatic mode off.

The removal process will be initiated by Reset-Button (I0.2), which activates cylinder Y2 (Q1.5). Reset-Button also disconnects signal lamp H2 and warning horn/buzzer H3. Automatic mode will be activated by pressing the Start-Button. When automatic mode is ON the green signal lamp H1 (Q0.0) should be ON as well. The next box should be ordered with output Q1.4.