Chapter 5 Basic Instructions Symbol: Explanation: When the conditional contact is enabled, the instruction PSTOP stops the execution of the program, and the PLC stops running. Example: When X0.0 is ON, Y0.0 is set to ON, Y0.1 remains OFF, and the PLC stops running. 5-25 Instruction code Operand Function PSTOP - Stopping executing the program in the PLC