Troubleshooting By Symptom - Mitsubishi Electric CC-Link IE Basic Reference Manual

9.2

Troubleshooting by Symptom

This section describes the troubleshooting by symptom. If the CC-Link IE Field Network Basic diagnostics does not solve the
problem, perform this troubleshooting.
When the transmission status is disconnected or unfixed
Check the following:
■Ethernet
Check item
Are the IP address and subnet mask of the master station/slave stations
correctly set?
Is the IP address already in use?
Is there any device having the same IP address as the master station/slave
stations within the same network address?
Is the same network address set to the master station and slave stations?
Is an access blocked?
Is any access from slave stations blocked in "IP Filter Settings" of the master
station.
Before an error was detected, has any device on the line, such as the master
station, slave station, or hub, been replaced with a device having the same IP
address as that of the device before replacement?
*1 Devices on Ethernet have a table of IP addresses and their corresponding MAC address, called the ARP cache. When a device on the
line is replaced with a device having the same IP address, the MAC address in the ARP cache becomes different from that of the
replaced device. This may cause incorrect data communications. The ARP cache is updated by resetting a device or after a certain time
has elapsed. The time varies depending on the device.
■CC-Link IE Field Network Basic
Check item
Are the devices specified in the refresh settings for the master station correct?
Are the devices specified in the refresh settings for the master station used in
other applications?
When cyclic data cannot be read/written from/to the slave station correctly
Check the following:
■CC-Link IE Field Network Basic
Check item
Is a slave station specified as a reserved station in "Network Configuration
Settings" of "Basic Settings" for the master station?
Has the accumulated number of timeouts of the slave station considered
*1
abnormal been counted up?
Has the accumulated number of disconnection detection of the slave station
considered abnormal been counted up?
*1 The accumulated number of timeouts and the accumulated number of disconnection detection can be checked in diagnostic information
1. For programs to acquire diagnostic information, refer to the following.
Page 48 Acquiring diagnostic information of slave stations
*1
Action
Check and correct the IP address and subnet mask of the master station/slave
stations.
Set a unique IP address to the master station/slave stations.
• Check and correct the IP address and subnet mask so that the network
addresses of the master station and slave stations match.
• Check and correct the subnet mask of the master station and slave stations
so that they match as normal values.
Check the security settings such as a firewall.
Allow an access from the IP address of the corresponding slave station.
Take either of the following actions:
• Wait until the ARP cache is updated. (The waiting time varies depending on
*1
the device.)
• Restart all devices on the line.
Action
Check and correct the refresh settings.
Check the settings and programs for the master station/slave stations, and
correct them if they are incorrect.
Action
Cancel the reserved station setting. ( Page 34 PARAMETER SETTINGS)
Check the following and take actions. (Page 46 When a station is
repeatedly disconnected and reconnected)
9.2 Troubleshooting by Symptom
9 TROUBLESHOOTING
9
45