User manual

Publication CNET-UM001C-EN-P - November 2005
4-6 Control I/O
Direct Connections for I/O Modules
In this example, assume that each distributed I/O module is configured for a
direct connection to the controller.
This table calculates the connections in this example.
ControlNet Network
I/O
I/O
I/O
I/O
I/O
I/O
Controller with ControlNet
Communication Module
ControlNet Adapter with
Digital I/O Modules
ControlNet Adapter with
Analog I/O Modules
ControlNet Adapter with
Digital I/O Modules
Table 4.3 Connection Calculations
System Connections Amount
Controller to local ControlNet communication module 0
Controller to ControlNet adapter
(1)
direct connection for digital I/O modules
direct connection for analog I/O modules
(1)
In this example, the remote ControlNet adapter uses the None communication format.
0
4
2
total connections used: 6
TIP
If you have a high number of modules, direct connections
to each module may not be feasible because the module
supports a finite number of connections, and direct
connections may require more resources than the module
has available.
In this case, use rack optimized connections (see the
section Rack Optimized Connections for I/O Modules) to
conserve connection use and network traffic.