Mitsubishi Electric MELSEC iQ-F FX5 Series User Manual page 158

When a station is disconnected from the network
The following is the action to be taken when a station in data link is disconnected.
Check item
Is the ambient temperature for the module outside the specified range?
If the above action does not solve the problem, perform the module communication test to check for hardware failure. (
Page 143 Module communication test)
When a station is repeatedly disconnected and reconnected
The following lists the actions to be taken when a station in data link is repeatedly disconnected and reconnected.
Check item
Do the used Ethernet cables conform to the Ethernet standard?
Is the station-to-station distance 100m or less?
Does the cabling condition (bending radius) meet the specifications?
Is any Ethernet cable disconnected?
Is the switching hub used in the system operating normally?
Is the time synchronization source station operating normally?
Are resets of other stations repeated?
Are other stations repeatedly powering on/off?
When the communication speed of the master station is set to 1Gbps and an
authentication Class B/A device with a communication speed of 100Mbps is
used, is "Communication Period Setting" set to "Basic Period" or "Normal-
Speed"?
If the above actions do not solve the problem, perform the module communication test to check for hardware failure. (
Page 143 Module communication test)
When communication is unstable
When cyclic transmission delay time is long or when a transient transmission timeout occurs, check the following items.
Check item
Is the L ER LED of the FX5-CCLGN-MS turned on?
Is the ambient temperature for the module outside the specified range?
Is any error shown in "Selected Station Communications Status Monitor" of
CC-Link IE TSN/CC-Link IE Field diagnostics?
Is there any noise affecting the system?
If the above actions do not solve the problem, perform the module communication test to check for hardware failure. (
Page 143 Module communication test)
10 TROUBLESHOOTING
156
10.4 Troubleshooting by Symptom
Action
Keep the ambient temperature within the specified range by taking action
such as removing heat source.
Action
If not, replace them with Ethernet cables that satisfy the Ethernet standard.
( Page 88 Ethernet cable)
Change the station-to-station distance to 100m or less.
Refer to the manual for the Ethernet cable, and if the bending radius exceeds
the specified range, correct the bending radius.
If an Ethernet cable is disconnected, replace the Ethernet cable.
• Check that a switching hub that conforms to the standard is used. (
Page 88 Switching hub)
• Power off and on the switching hub.
Take action by referring to the manual for the module of the time
synchronization source station.
Avoid unnecessary reset since a station is disconnected while resetting.
Avoid unnecessary power-off, since a station is disconnected while turned off.
For an authentication Class B/A device with a communication speed of
100Mbps, set "Communication Period Setting" to "Low-Speed".
Action
Perform troubleshooting to be performed when the L ER LED turns on. (
Page 140 When the L ER LED turns on)
Keep the ambient temperature within the specified range by taking action
such as removing heat source.
If an error occurs, perform a module communication test.
Change the installation of the modules and wiring so that the system is not
affected by noise.