What is a Watchdog in PLC?

A watchdog in a PLC (Programmable Logic Controller) is a crucial component designed to monitor and ensure the proper operation of the system. Its primary role is to detect and respond to faults or failures within the PLC or its processes. By continuously monitoring the execution of the control program, the watchdog can identify situations where the PLC may be stuck or malfunctioning. When such a condition is detected, the watchdog initiates a corrective action, such as resetting the PLC or switching to a backup system. This mechanism is essential for maintaining the reliability and stability of industrial automation systems, preventing costly downtime and ensuring the smooth operation of automated processes. The concept of a watchdog is applicable not only in PLCs but also in various other computing and electronic systems where reliability is critical. The watchdog acts as a safety net, providing an additional layer of protection to safeguard against unexpected failures and ensure continuous operation.