Troubleshooting - Mitsubishi Electric MELSEC-L LD75P User Manual

15.3

Troubleshooting

(1) Troubleshooting using the LEDs
Check items and corrective actions for troubleshooting using the indicator LEDs of the LD75 are described below.
(a) When the RUN LED turns off
Check item
Is the power supplied?
Is the power supply capacity sufficient?
Is the module connected correctly?
If there is no problem on the above check items, a watchdog timer error may have occurred. Reset the CPU
module and check that the RUN LED turns on.
If not, the possible cause is a hardware failure. Please consult your local Mitsubishi representative.
(b) When the ERR. LED turns on
Check item
Is there a system error?
(c) When the ERR. LED and axis LED flash
Check item
Is there an axis error?
(d) When all LEDs turn on
Reset the CPU module and check that the module is in the normal status.
If all LEDs still turn on, the possible cause is a hardware failure. Please consult your local Mitsubishi
representative.
644
Check that the voltage supplied to the power supply module is within the rated range.
Calculate the total current consumption of the connected modules (CPU module, I/O modules, and
intelligent function modules) and check that the power supply capacity is not insufficient.
• Check that the connector on the side of the module is properly inserted.
• Check that the module joint levers are locked.
An error may have occurred in the CPU module. Check the error and take a corrective action.
Check the error code and take the action described in the following. ( Page 650, Section 15.5)
Action
Action
Action