Tag Data Link Problems - Omron CJ1W-EIP21 Operation Manuals

13 Troubleshooting

13-6-4 Tag Data Link Problems

Tag data is not concurrent.
At startup, some of the receive data is FALSE
when it should be TRUE.
The tag data links start and stop communicating
intermittently.
13-50
Check the following items and correct the user program.
• Data concurrency is maintained for each connection between the CPU
Unit and the built-in EtherNet/IP port. To maintain data concurrency for
tag data links, set a refreshing task for the network variables that are
assigned to tags. Refer to 7-1-7 Concurrency of Tag Data Link Data for
details.
• Refer to the product manuals for products from other manufacturers.
• When received data is used in the ladder program, use the All Tag Data
Links Operating Information in Communications Status 1, or the corre-
sponding element of the Target Node PLC Operating Flags as a condi-
tion. If the Target Node PLC Operating Flags is used, the Controller
status must be included in tag sets of both the sending and receiving
nodes.
• If the Output OFF function (Output Inhibit) is enabled in the output (pro-
duce) tag settings, all of the output data will be OFF if a fatal error
occurs in the CPU Unit. Check the status of the output (producer) PLC.
• Check whether the baud rate is set to 10 Mbps, or a 10M or 100M
repeater hub is being used. The tag data link performance is based on
the use of Ethernet switches. The bandwidth listed in the specifications
is achieved when the Unit auto-negotiates to full-duplex at 100 Mbps.
• Refer to 13-1 Checking Status with the Network Configurator for details
on checking the error counters on the Monitor Device Window's Ether-
net Information Tab Page. The error and discarded packet counters
indicate problems such as noise in the communications path, the use
of substandard cables, damaged cables/connectors, loose connectors,
abnormally high communications load, or incorrect wiring (loops) in the
Ethernet switch wiring.
• Contact the Ethernet switch manufacturer to determine whether there
are any problems with the transfer capacity of the Ethernet switches in
the communications path. If Ethernet switches are arranged in a cas-
cade connection, there may be a heavy load concentrated at a mid-
level Ethernet switch. In the EtherNet/IP Unit itself, processing is per-
formed with a higher priority than message communications, so specifi-
cations provide for a 6,000 pps bandwidth for other CPU Units in tag
data link performance only.
• Refer to 13-1 Checking Status with the Network Configurator for details
on checking the connection status on the Monitor Device Window's
Connection Tab Page. Eliminate any errors, which can be identified in
the tables in 13-3 Connection Status Codes and Error Processing.
CJ-series EtherNet/IP Units Operation Manual for NJ-series CPU Unit (W495)