When "Run" Led On The Safety Master Module Turns Off Suddenly - Mitsubishi Electric MELSEC QS Series User Manual

9
TROUBLESHOOTING

9.3.3 When "RUN" LED on the safety master module turns OFF suddenly

9
- 20 9.3 Check with LEDs (2) - During System Operation
9.3.3 When "RUN" LED on the safety master module turns OFF suddenly
The "RUN" LED turned
OFF suddenly.
Is "POWER" LED on the safety
power supply module ON?
Yes
Is "ERR." LED on the safety
No
CPU module flashing?
Yes
Reset the safety CPU module with
the RUN/STOP/RESET switch.
Did the "RUN." LED on the safety
master module turn ON?
Yes
Check the operations of the
following hardware and identify a
faulty module.
(1) Safety power supply module
(2) Safety CPU module
(3) Safety main base unit
No
Refer to the troubleshooting of
the safety power supply module.
No
The hardware of the safety master
module may be faulty.
Replace the safety master module.