Error (Err) Indicator Lamp (Statuses: On, Flashing, Off - Mitsubishi Electric FX3S Series User Manual

FX /FX /FX
3S 3G 3GC
Built-in Positioning Functions

13.1.5 ERROR (ERR) indicator lamp (Statuses: ON, flashing, OFF)

Lamp
status
ON
Flashing
OFF
B - 180
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/FX /FX PLC User's Manual - Positioning Control Edition
3U 3UC
Status of PLC
A watchdog timer error may have
been detected, or the hardware of the
PLC may be damaged.
The PLC has one of the following
errors:
· Parameter error
· Syntax error
· Circuit error
Errors that can stop the PLC are not
detected.
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Troubleshooting
1) Stop the PLC, turn the power OFF, and then turn the power
ON again. If the ERROR (ERR) indicator lamp goes out,
check to see if a watchdog timer error has been detected, and
take one of the following measures.
- Review the program.
The maximum value of the scanning time (D8012) should
not be larger than the set value of the watchdog timer
(D8000).
- The interrupt input and the pulse catch input should not be
turned on and off too frequently during 1 scan time.
- The frequency of the pulse input to the high-speed counter
should not exceed the specified range (duty:50%)
- Add several WDT instructions.
Set several WDT instructions in the program so that the
watchdog timer can be reset several times during 1 scan
time.
- Change the set value of the watchdog timer.
Using the program, change the set value of the watchdog
timer (D8000) so that the set value of the watchdog timer
(D8000) can be larger than the maximum value of the
scanning time (D8012).
2) Remove the PLC, and put it on a workbench. Supply another
source of power to the PLC.
If the ERROR (ERR) indicator lamp does not light, the cause
of the problem may be noise. In this case, take the following
measures.
- Check the grounding line, and change the wiring route and
the installation place.
- Adopt a noise filter for the power supply line.
3) If measures 1) and 2) do not turn the ERROR indicator lamp
O F F , p l e a s e c o n t a c t y o u r l o c a l M i t s u b i s h i E l e c t r i c
representative.
Diagnose the PLC (PC), or check the programs using the
programming tool.
For countermeasures, refer to the following manual of the applied
PLC.
If an operation error is detected on the PLC, diagnose the PLC
(PC), or check the programs using the programming tool. There
is a good possibility that an "I/O configuration error", "parallel link/
communication error", or "operation error" has been detected.
13 Troubleshooting
13.1 LED Indicator Lamp Check
Programming manual