Chapter 9 Troubleshooting; Troubleshooting Procedure; Checking With Leds; Checking The Pwr Led - Mitsubishi Electric FX5U 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 124 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 120 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 122 Module diagnostics (CPU Diagnostics))
5.
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 turned on, 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
120
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 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 116 Battery)