Rockwell Automation 1785-CHBM ControlNet PLC-5 Hot Backup System User Manual - Manual (Page 32)

Publication 1785-UM024B-EN-P - January 2003
3-6 Installing and Configuring Your ControlNet PLC-5 Backup System
Note that the message number for the Consume Buffer ID
message must match the message number of the corresponding
Produce Buffer ID message. The node number and message
number are used together to identify the specific message.
3. In the Requested Packet Interval field, enter an RPI value for
this message from 1 to 32,767. (For purposes of this example,
we will use an RPI value of 5ms.)
In general, the RPI value must be no less than the NUT value,
but less than 2 times the NUT value. This value must be the
same in both PLC-5s.
4. In the Input Size field, enter a value of 5 and click OK.
The Consume Buffer ID scheduled message is inserted in your
ControlNet Configuration for the odd-numbered node. The
corresponding Produce Buffer ID scheduled message is
automatically inserted for the even-numbered node.
5. From the main RSNetWorx for ControlNet screen, right click
on the second PLC-5 and choose Scanlist Configuration.
6. Right click on the odd-numbered node (Node 1 in this example)
and choose Insert Connection.
The Connection dialog box appears. The To Node field is
already filled in for you. This number indicates the node number
from which you will receive the Consume Buffer ID message. In
your ControlNet backup system, the odd-numbered node will
receive the message from the even node, and vice versa.
7. Repeat steps 2 through 4, creating a Consume Buffer ID message
for the even-numbered node.
8. Record the Produce Buffer ID and Consumer Buffer ID message
numbers from the odd-numbered PLC-5 below:
Produce Buffer ID message number:__________
Consume Buffer ID message number:__________
You will use these numbers later in the configuration process.