NAiS FP Series User Manual page 246

FPΣ
Check of input condition 4: Input indicator LEDs are on
Procedure
Monitor the input condition using a programming tool.
- If the input monitored is off, there is probably an abnormality with the input unit.
Please contact your dealer.
- If the input monitored is on, check the leakage current at the input devices (e.g.,
two-wire type sensor) and check the program again, referring the following:
Check for the duplicated use of output and for the output using the high- level
instruction.
Check the program flow when a control instruction such as Master control relay
or Jump is used.
12.2 Troubleshooting
12 - 9