User Program Triggered Safe Stop

What does 8704 mean?

This indicates that the safety PLC's own user-defined program has intentionally initiated a safe stop condition. This is typically a designed response to a specific condition detected by the application logic, such as a sensor input or an internal process state deemed unsafe. It is usually not a fault of the PLC hardware itself, but rather a protective action taken by the software.

Additional Steps

Steps 1–2 are listed in Priority Fix.

1. 3

   Clear the condition that caused the safe stop, or reset the PLC's safe stop state via the HMI/SCADA if appropriate and safe to do so.