Omron CJ Series Operation Manual page 29

• You cannot upload or download information for forced refreshing with the Sysmac Studio.
After downloading data that contains forced refreshing, change to RUN mode and then use the Sys-
mac Studio to perform the operation for forced refreshing.
Depending on the difference in the forced status, the control system may operate unexpectedly.
• Do not specify the same address for the AT specification for more than one variable.
Doing so would allow the same entity to be accessed with different variable names, which would
make the user program more difficult to understand and possibly cause programming mistakes.
General Communications
• When you use data link communications, check the error information given in the status flags to
make sure that no error has occurred in the source device. Write the user program to use the
received data only if there is no error. If there is an error in the source device, the data for the data
link may contain incorrect values.
• Unexpected operation may result if inappropriate data link tables are set. Even if appropriate data link
tables have been set, confirm that the controlled system will not be adversely affected before you
transfer the data link tables. The data links start automatically after the data link tables are trans-
ferred.
• All CPU Bus Units are restarted when routing tables are transferred from Support Software to the
CPU Unit. Restarting these Units is required to read and enable the new routing tables. Confirm that
the system will not be adversely affected by restarting before you transfer the routing tables.
• Tag data links will stop between related nodes while tag data link parameters are transferred during
Controller operation. Confirm that the system will not be adversely affected before you transfer the
tag data link parameters.
EtherNet/IP Communications
• All related EtherNet/IP nodes are reset when you transfer settings for the built-in EtherNet/IP port
(including IP addresses and tag data links settings). This is performed to read and enable the set-
tings. Confirm that the system will not be adversely affected by resetting nodes before you transfer
the settings.
• If EtherNet/IP tag data links (cyclic communications) are used with a repeating hub, the communica-
tions load on the network will increase. This will increase collisions and may prevent stable communi-
cations. Do not use repeating hubs on networks where tag data links are used. Use an Ethernet
switch instead.
EtherCAT Communications
• Make sure that the communications distance, number of nodes connected, and method of connec-
tion for EtherCAT are within specifications.
Do not connect EtherCAT communications to EtherNet/IP, a standard in-house LAN, or other net-
works. An overload may cause the network to fail or malfunction.
• Malfunctions or unexpected operation may occur for some combinations of EtherCAT revisions of the
master and slaves. If you disable the revision check in the network settings, use the Sysmac Studio
to check the slave revision settings in the master and the actual slave revisions, and then make sure
that functionality is compatible in the slave manuals or other references. You can check the actual
slave revisions from the Sysmac Studio or on slave nameplates.
• After you transfer the user program, the CPU Unit is restarted. Communications with the EtherCAT
slaves are cut off for up to 45 seconds. During that period, the slave outputs behave according to the
slave settings.
Before you transfer the user program, confirm that the system will not be adversely affected.
• If the Fail-soft Operation parameter is set to stop operation, process data communications will stop
for all slaves when an EtherCAT communications error is detected in a slave. For this reason, if
Servo Drives are connected, the Servos for all axes will be turned OFF. Make sure that the Fail-soft
Operation parameter setting results in safe operation when a device error occurs.
CJ-series PROFIBUS Master Unit Operation Manual for NJ-series CPU Unit (W509) 25