Use PLC, solenoid valve, relay and cylinder design circuit to control the reciprocating motion of cylinder (the simplest reciprocating motion), and find the wiring diagram and circuit diagram.

Requirements as shown in the figure below:

Note: X000 is the left limit, X00 1 is the right limit, X002 is the stop button and X003 is the start button. Y000 is the output of relay KA 1, and Y00 1 is the output of relay KA2.

Working principle: X003 is powered on, M0 is electrically self-locked, cylinder left limit X000 is closed, M500 is set, Y0 is powered on, KA 1 is powered on, double-ended electromagnetic directional valve A is powered on, and the cylinder is extended.

After the oil cylinder is extended in place, the right limit X00 1 is powered on, the reset M500, Y000, Y00 1 are powered off, KA2 is powered off, and the double-ended electromagnetic directional valve is powered off, and the oil cylinder retracts.

When the cylinder retracts to its original position, the left limit X000 of the cylinder is closed. Repeat steps 3 and 4, and the cylinder will reciprocate.