Mitsubishi Electric MELSEC iQ-RJ71EN71 User Manual page 218

When the D LINK LED turns off or is flashing
When the D LINK LED turns off or is flashing, check the following.
Check item
Is the master station operating normally?
Is the master station connected to the network?
Do the used Ethernet cables conform to the Ethernet standard?
Does the station-to-station distance meet the specifications?
Does the cabling condition (bending radius) meet the specifications?
Is any Ethernet cable disconnected?
Are 121 or more slave stations connected?
Is a switching hub connected in ring topology?
Are other stations connected to the master/local module operating normally?
Is the switching hub used operating normally?
Check that the cables are not connected as described below.
• Both P1 and P2 are connected to the same switching hub.
• The network is configured in ring topology although "Network Topology"
under "Basic Settings" of the master station is set to "Line/Star".
• The network is configured in star topology although "Network Topology"
under "Basic Settings" of the master station is set to "Ring".
• The network is incorrectly configured in ring topology.
Are station numbers unique?
The devices having different network types (such as CC-Link IE Controller
Network and CC-Link IE Controller Network) are connected to the same
network line.
If the above actions do not solve the problem, perform the following tests to check for an error.
• Module communication test ( Page 221 Module communication test)
• Cable test ( Page 239 Cable Test)
4 TROUBLESHOOTING
216
4.1 Checking with LED
Action
• If an error has occurred in the CPU module on the master station, eliminate
the cause of the CPU module error. ( MELSEC iQ-R CPU Module User's
Manual (Application))
• Check if the master station is performing data link using CC-Link IE Field
Network diagnostics. ( Page 223 Checking the Network Status)
When the master station and submaster station is the module other than the
MELSEC iQ-R series, and there is a local station of the MELSEC iQ-R series
module, refer to the following.
Page 380 Precautions for When Connecting the Module to the
Conventional Product
Check if the master station is performing data link using CC-Link IE Field
Network diagnostics. ( Page 223 Checking the Network Status)
Replace the cables with the Ethernet cable which conforms the standard. (
MELSEC iQ-R Ethernet/CC-Link IE User's Manual (Startup))
Set the station-to-station distance within range. ( MELSEC iQ-R Ethernet/
CC-Link IE User's Manual (Startup))
Refer to the manual for the Ethernet cable, and correct the bending radius.
Replace the Ethernet cable.
Change the connection of the slave stations to 120 stations or less.
Configure the network in ring topology without a switching hub.
• Check if the modules on the other stations are performing data link using
CC-Link IE Field Network diagnostics. ( Page 223 Checking the Network
Status)
• Check the operation status of modules on other stations. ( User's manual
for the module used)
• Check if the switching hub which conforms the standard is used. (
MELSEC iQ-R Ethernet/CC-Link IE User's Manual (Startup))
• Power off and on the switching hub.
Correct the wiring.
When the system does not contain a switching hub, take any of the following
actions:
• For line topology, disconnect an Ethernet cable (either P1 or P2) connected
to any station on the network. The network topology will become a line
topology and data link will start.
• For ring topology, set "Network Topology" under "Basic Settings" to "Ring"
and rewrite the parameters to the CPU module.
When the system contains a switching hub, take any of the following actions:
• Check if "Network Topology" under "Basic Settings" is set to "Ring". Because
the network cannot be configured in ring topology which contains a switching
hub, set "Network Topology" to "Line/Star" and rewrite the parameters to the
CPU module. When data link starts across the entire network, this procedure
is successfully completed.
• Disconnect one Ethernet cable connected to the switching hub and power off
and on the hub. (Repeat this operation until data link starts over the
network.)
• When data link starts over the network, check the network configuration
using CC-Link IE Field Network diagnostics.
Change the duplicated station number.
Divide it into CC-Link IE Controller Network (Ethernet cable) and the network.
After taking the above actions, power off and on or reset all stations where the
error was detected.