The debugging of Siemens PLC programs can be divided into two processes: simulation debugging and on-site debugging. It is crucial to conduct a thorough check of the PLC's external wiring first. The external wiring is problem-free. For safety reasons, the main circuit is disconnected. The external wiring is scanned and powered on using the pre-written test program to identify any wiring faults. Once the wiring is confirmed to be correct, the main circuit is reconnected, and the simulation-debugged program is loaded into the user's memory for debugging. This continues until all components function properly and can coordinate to complete the overall control function.