Adding 1756-Cnb Modules To Expand The Network - Allen-Bradley ControlLogix User Manual

Adding 1756-CNB Modules to
Expand the Network
Remote Chassis #1
Remote Chassis #2
The ControlNet network in the example application can support a maximum
of 64 remote bidirectional connections. To expand the network you can add
additional 1756-CNB interface modules to the local chassis and connect
them to remote 1756-CNB modules on the same or another ControlNet
network. Each 1756-CNB module added to the local chassis can
communicate with a maximum of 64 connections. For example, the system
shown in the following figure can use one controller to support a theoretical
maximum of 128 remote connections.
Local Chassis
Logix5550
Controller
1756-CNB
1756-CNB
(Node 6)
(Node 1)
PC with
1784-KTCX15
Interface
1756-CNB
(Node 3)
Important: The number of connections that can actually be supported on a
network is dependent upon many factors, including the network
parameter settings. For example, at an RPI of 5ms, not more
than 10 to 12 connections can be supported, at an RPI of 2ms
only 4 connections can be supported.
Adding an I/O Chassis to an Existing ControlNet Network
Remote Chassis #3
1756-CNB
1756-CNB
(Node 2) (Node 12)
Remote Chassis #4
1756-CNB
(Node 31)
11-17
To Other
Devices
1756-6.5.3 - December 1999