Chapter 9 Troubleshooting; Troubleshooting Procedure; Checking With Leds; Checking The Pwr Led - Mitsubishi Electric MELSEC iQ-F FX6U Hardware User Manual

9
TROUBLESHOOTING
Details on errors occurring in the system, their causes, and corrective actions are explained below.
For details on troubleshooting for each module, refer to the manuals for the module.
Saving the programs and devices used at the occurrence of an error helps in identifying the cause of the error.
(Page 177 Backing Up the Data)
9.1

Troubleshooting Procedure

If an error occurs, perform troubleshooting in the following order.
1.
Check that each module is properly mounted and wired.
2.
Check the LEDs of the CPU module. (Page 172 Checking with LEDs)
3.
Check the LEDs of each intelligent function module. (Manuals for each module)
4.
Connect the engineering tool and execute the Module Diagnostics (CPU Diagnostics). The error cause and the action to
be taken can be displayed. (Page 174 Module diagnostics (CPU diagnostics))
5.
If the cause could not be specified by Module diagnostics (CPU Diagnostics), check the error history from the event
history of the engineering tool to identify the cause. (Page 175 Event history)
6.
Check the cause of the error and take corrective actions.
9.2

Checking with LEDs

Check the module status with LEDs as a means to perform the primary diagnosis.

Checking the PWR LED

If the PWR LED is turned off, check the following items.
Item to check
Measure the voltage supply to the CPU module.
Remove extension modules and all wiring other than the
one for the power supply, and turn on the power supply.
If the PWR LED still does not turn on even after the items shown above are checked, there may be a hardware issue.
Consult your local Mitsubishi Electric representative.

Checking the BAT LED

If the BAT LED is flashing, check the following items.
The LED is valid when the optional battery is installed and the LED is set to "display" for battery errors by using the parameter.
Item to check
Check the installation of the battery.
Check the battery voltage.
9 TROUBLESHOOTING
172
9.1 Troubleshooting Procedure
Cause and action
If the power source is not supplying the proper voltage, provide a power source that does.
If the PWR LED turns on in this condition, the 24 V DC service power supply may be shorted or
overloaded. Reconnect the modules and wire one by one to identify the cause.
Cause and action
Install the battery properly.
If the battery voltage is reduced, replace the battery with a new one.
Battery voltage can be monitored with PLC data register SD8005.
(Page 168 Battery)