The L Run Led Does Not Turn On; The L Err. Led Is On Or Flashing - Mitsubishi Melsec-L Series User Manual

8.4.2

The L RUN LED does not turn on

Check the following:
After changing a remote station number, power off and on the system.
After data link is established, the transmission speed setting
of the master station was changed.
A communication cable is incorrectly wired.
The station number setting switch is incorrectly set.
A station number is set outside the control range of the
master station.
The operation setting switch of the master station is
incorrectly set.
*1 Check for short circuit, reverse connection, disconnection, excessive pressure, terminating resistors, overall cable
distance, branch line distance (overall branch line length, maximum branch line length), and surrounding environment
such as a noise.
If the L RUN LED does not turn on even after the above actions are taken, the possible cause is a hardware failure.
Please consult your local Mitsubishi service center or representative, explaining a detailed description of the problem.
8.4.3

The L ERR. LED is on or flashing

Check the following:
Switch setting is changed after power-on.
A communication cable is incorrectly wired.
*1 Check for short circuit, reverse connection, disconnection, excessive pressure, terminating resistors, overall cable
distance, branch line distance (overall branch line length, maximum branch line length), and surrounding environment
such as a noise.
If the L ERR. LED remains on or flashing even after the above actions are taken, the possible cause is a hardware
failure.
Please consult your local Mitsubishi service center or representative, explaining a detailed description of the problem.
60
Check item
Check item
Action
Power off and on the system.
*1
Correct the wiring.
( Page 36, Section 6.3)
Correct the station number with meeting the following:
• The number is 1 to 64.
• The ones digit is 0 to 9.
• Do not set the number using the output hold setting switch
and response speed setting switch.
After changing a remote station number, power off and on
the system.
• Check that the numbers of remote stations occupied by
the master station are 1 to 64.
• Check that station numbers set on remote stations are
within the control range of the master station.
After changing a remote station number, power off and on
the system.
Correct the setting. ( Page 15, CHAPTER 2)
After correcting the setting, power off and on the system or
reset the CPU module.
Action
Return the switch setting to the status before the switching.
*1
Correct the wiring.
( Page 36, Section 6.3)