Troubleshooting By Symptom; When The Run Led Flashes Or Turns Off; When The Err Led Turns On; When The Alm Led Turns On - Mitsubishi Electric MELSEC iQ-R Series User Manual

3.3

Troubleshooting by Symptom

When the RUN LED flashes or turns off

When flashing
Check item
Is the module in offset/gain
setting mode?
When turning off
Check item
Is the power supplied?
Is the capacity of power supply module enough?
Is the module connected properly?
The case other than the above

When the ERR LED turns on

When turning on
Check item
Has any error occurred?

When the ALM LED turns on

When turning on
Check item
Has any alert output occurred?
3 TROUBLESHOOTING
102
3.3 Troubleshooting by Symptom
Cause
In the module parameter setting of the
engineering tool, the programmable controller
power supply has been turned off and on, or
the CPU has been reset when the operation
mode is offset/gain setting mode.
The G(P).OFFGAN instruction has been
executed with the mode switched to offset/
gain setting mode.
The value in the mode switching setting has
been changed and the mode has been
switched to offset/gain setting mode.
Action
Set the operation mode to the normal mode (D/A conversion process) in the
module parameter setting of the engineering tool, and turn off and on the
programmable controller power supply or reset the CPU.
Review the program using the G(P).OFFGAN instruction and check whether
the mode switching is wrongly executed.
Review the program using Mode switching setting and check whether the
mode switching is wrongly executed.
Action
Check that the supply voltage of power supply module is within the rated
range.
Check that the power capacity is enough by calculating the current
consumption of connected modules, such as the CPU module, I/O modules,
and intelligent function modules.
Check the module connection.
Reset the CPU module, and check that the RUN LED turns on.
If the RUN LED remains off, the module may be failed. Please consult your
local Mitsubishi representative.
Corrective action
Check Latest error code, and take actions described in the error code list.
Corrective action
Check the alert output upper limit flag or alert output lower limit flag. For the
corrective action, take actions described in the alarm code list. (Page 110
Alarm Code List)