What feature do diagnostic output modules possess regarding the actual state of the output point?

Diagnostic output modules are designed to provide feedback regarding the actual state of the output point. This means they can determine whether the output point is in the expected state (either ON or OFF) based on the commands sent from the PLC. This feature is pivotal, as it allows for monitoring and troubleshooting of the system. By knowing the actual state, operators and maintenance personnel can quickly identify discrepancies, which can indicate issues such as wiring problems, load failures, or module malfunctions.

Understanding the actual state is crucial for ensuring safety and reliability in automated processes, as it allows for immediate corrective actions to be taken if the output does not match the commanded state. This capability enhances the operational integrity of the automation system and aids in preventive maintenance. Thus, the ability of diagnostic output modules to determine and report the actual state of the output point underscores their importance in advanced PLC applications.