Rockwell Automation 1734-ACNR POINT I/O ControlNet Adapter User Manual - Manual (Page 21)

1 Publication 1734-UM008B-EN-P - August 2005
Chapter
3
Plan to Use Your Adapter
Chapter Objectives This chapter explains how the adapter operates on a ControlNet
network and provides information to assist in configuring your
system. This chapter contains the following information.
• Overview of adapter operation
– I/O connections
– Rack connections
– Direct connections
– Explicit messaging communications
– Software requirements
• Understanding ControlNet I/O
– Scheduled data-transfer connections on a ControlNet network
Overview of
Adapter Operation Connections are established between a scanner and an adapter to
exchange input and output data on the network. Status information is
transferred along with the I/O data.
I/O Connections
The adapter supports 25 direct and 5 rack I/O connections to the
POINT I/O modules. From a single 1734-ACNR adapter, multiple
controllers can establish I/O connections, up to a maximum of 5 rack
I/O connections per adapter. You must use direct connection with
analog and specialty I/O modules.
Make multiple rack connections to permit multiple controllers to
connect to I/O over a single 1734-ACNR adapter.
The number of connections that can actually be supported on a
network depends on the following.
• ControlNet parameters (NUT, RPI, API)
• POINT I/O configuration by itself (number and types of
modules)
• Type of connection to these modules (direct connection, rack
connection)