Cause : External Fault (Input Terminal S4) comes when external fault at multi-function input terminal S4. An external device has tripped an alarm function.

1. Remove the cause of the external fault and reset the multi-function input value.
2. Wiring is incorrect.
   • Ensure the signal lines have been connected properly to the terminals assigned for external fault detection (H1-.... = 20 to 2F).
   • Reconnect the signal line
3. Multi-function contact inputs are set incorrectly.
   • Check if the unused terminals have been set for H1-XX = 20 to 2F (External Fault).
   • Change the terminal settings.