Display Unit; Transmission From An External Device; Operating Status Of The Cpu Module - Mitsubishi MELSEC L Series User Manual

15.3.11

Display unit

If the display unit behaves abnormally, check the following items.
Nothing was displayed on the screen but the display came
back on after a button is pressed.
"DISPLAY ERROR" (error code: 2900, 2901, 2902) has
occurred in the CPU module.
"DISPLAY UNIT ERROR" is displayed on the display unit.
The character on the screen is incorrect even though the
language setting is correct. Or any character that is not
applicable has been displayed.
If the display unit is not recovered even after taking the above actions, the possible cause is a hardware failure.
Please consult your local Mitsubishi service center or representative, explaining a detailed description of the problem.
15.3.12

Transmission from an external device

If no response is returned from an external device, check the following items.
More than one external device is communicating with the
CPU module.
The data logging function is used.
If communication cannot be performed even after taking the above actions, the possible cause is a hardware failure.
Please consult your local Mitsubishi service center or representative, explaining a detailed description of the problem.
15.3.13

Operating status of the CPU module

If it takes time for the CPU module to switch the operating status, check the following item.
The data logging function is used.
If it takes time for the CPU module to switch the operating status even after taking the above action, the possible cause
is a hardware failure.
Please consult your local Mitsubishi sevice center or representative, explaining a detailed description of the problem.
118
Check item
Check item
Check item
Action
The time set to keep the backlight on has elapsed.
Check the setting.
Power off the system and check for connection.
( MELSEC-L CPU Module User's Manual (Function
Explanation, Program Fundamentals))
The possible cause is a hardware failure of the display unit.
Please consult your local Mitsubishi service center or
representative, explaining a detailed description of the
problem.
Action
• Adjust the service processing time in the parameter
setting.
• Adjust the "Check at Communication Time" or "Retry
Times" value.
• Check the condition of the cables, connected device
(personal computer), and CPU module.
Refer to the troubleshooting section of the following manual.
MELSEC-L CPU Module User's Manual (Data Logging
Function)
Action
Refer to the troubleshooting section of the following manual.
MELSEC-L CPU Module User's Manual (Data Logging
Function)