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4 TROUBLESHOOTING
4.1 Checking with LED
217
4
When the L ERR LED turns on
When the L ERR LED turns on, check the following.
If the above actions do not solve the problem, perform troubleshooting for when communication is unstable. (
When communication is unstable)
When the L ER LED turns on
When the L ER LED turns on, check the following.
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)
• Troubleshooting for when communication is unstable (
Page 253 When communication is unstable)
Check item
Action
Are the Ethernet cables used normally?
• Check if the Ethernet cable which conforms the standard is used. (
MELSEC iQ-R Ethernet/CC-Link IE User's Manual (Startup))
• Check if the station-to-station distance is set within range. (
MELSEC
iQ-R Ethernet/CC-Link IE User's Manual (Startup))
• Check if the Ethernet cables are not disconnected.
Is the switching hub used operating normally?
• 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.
Are other stations connected to the master/local module operating normally?
• Check if the modules on the other stations are performing data link using
CC-Link IE Field Network diagnostics. (
• Check the operation status of modules on other stations. (
User's
manual for the module used)
Is "Module Operation Mode" under "Application Settings" of the master station
set to "Online"?
Set "Module Operation Mode" under "Application Settings" of the master
station to "Online".
Is there any source of noise near the module or cables?
Change the location of the module or cables.
Is "Network Topology" under "Basic Settings" of the master station set to
"Ring"?
Check if the ring topology is correctly configured for the port where the L ER
LED is on. (
MELSEC iQ-R Ethernet/CC-Link IE User's Manual (Startup))
Check item
Action
Are the Ethernet cables used normally?
• Check if the Ethernet cable which conforms the standard is used. (
MELSEC iQ-R Ethernet/CC-Link IE User's Manual (Startup))
• Check if the station-to-station distance is set within range. (
MELSEC
iQ-R Ethernet/CC-Link IE User's Manual (Startup))
• Check if the Ethernet cables are not disconnected.
Is the switching hub used operating normally?
• 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.
Is there any source of noise near the module or cables?
Change the location of the module or cables.
Is "Network Topology" under "Basic Settings" of the master station set to
"Ring"?
Check if the ring topology is correctly configured for the port where the L ER
LED is on. (
MELSEC iQ-R Ethernet/CC-Link IE User's Manual (Startup))
Summary of Contents for MELSEC iQ-R04ENCPU
Page 2: ......
Page 61: ...1 FUNCTIONS 1 3 IP Packet Transfer Function 59 1 ...
Page 385: ...383 I Transient transmission 15 ...
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