If The Sd/Rd Led Does Not Flash When Data Is Sent - Mitsubishi Electric MELSEC-L SERIES Basic User Manual

16.4.3

If the SD/RD LED does not flash when data is sent

The following table lists the items to be checked and the actions to be taken if the SD LED does not flash when data is
sent.
Check item
Is the ERR. LED or COM.ERR. LED on?
Are the cables properly connected?
Are the parameter settings correct?
Is the program correct?
If the action above does not solve the problem, perform the following tests on the E71 to check for hardware error.
• Hardware test (
• Self-loopback test (
Remove the cause that turned on the ERR. LED or COM.ERR. LED.
Check the cable connection. In addition, perform a line test to check if
there is a problem with the cable connection and the Ethernet line.
( Page 322, Appendix 5)
Correct the IP addresses of the own station and the communication
destination, router setting, and subnet mask setting.
Correct the send program of the connected device.
Page 333, Appendix 6.2)
Page 332, Appendix 6.1)
CHAPTER 16 TROUBLESHOOTING
Action
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