The output indicator lights of Mitsubishi PLCs are installed on their respective output modules. These lights indicate the status of the PLC output signals. When an output indicator light is off, check and determine the cause of the fault.
Possible reasons why the output module or output points may not light up include:
1. When using computer software to monitor the program and confirm that the corresponding output point of the PLC is "1" and there is an output signal from the connected peripheral device, the indicator light is still not lit.
It may be due to internal damage to the PLC output indicator.
2. When using computer software monitoring program, confirm that the corresponding output point of PLC is "1" and there is no output signal from the connected peripheral equipment.
Possibility 1: Is it in PLC simulation mode?
Possibility Two: The output interface and indicator light circuits are all damaged. In this case, it can only be returned to the factory for repair (due to excessive output load and short circuit causing a drop in the internal power supply voltage of the Mitsubishi PLC, triggering its protection mechanism).
3. When the fault occurs in the expansion unit, it may be due to a poor connection between the basic unit and the expansion unit;
Measure the output voltage of the Mitsubishi PLC and check the module installation and connection. After confirming that it is correct, the output module should be replaced or repaired and handled.
