Rockwell Automation AADvance Controller Solutions Handbook - Manual (Page 25)

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Document: 553631
(ICSTT-RM447J_EN_P) Issue: 09:
1-13
Main Components
Hardware Components
Each controller is built from a standard range of modules and assemblies; it consists of
processor modules, a processor base unit, digital and analogue I/O modules, I/O base
units and termination assemblies all of which are assembled as follows:
 A processor module is installed into a processor base unit that can hold up to 3
processor modules.
 3-way I/O base units are connected to the processor base unit and to each other.
Each I/O base unit holds up to three I/O modules and termination assemblies. A
controller can have up to 8 I/O base units on each of two I/O busses, giving a total
capacity for up to 48 I/O modules.
 I/O modules are connected to field devices through external connectors on the
termination assemblies.
The processor module and base units are designed for use as either single, dual or
triple redundant processor module arrangements. The base processor base unit
provides external connections for Serial and Ethernet networks and the dual
redundant system power inputs.
The I/O base unit plugs directly into the processor base unit and carries the redundant
system power for the modules, the processor commands across a command bus and
I/O data across individual data response busses.
I/O base units also directly plug into each other and are secured and held in place by a
clamping arm and retaining clips; hence, a controller becomes a complete mechanically
and electrically interconnected assembly without the need for additional wiring or
cabling. The I/O modules are also designed for use in single or dual or triple redundant
configurations.
Termination assemblies are matched to a specific type of I/O module and have terminal
blocks that provide 8 or 16 connections for the wiring to the field elements. The
termination assemblies for dual and triple arrangements have channel to channel
isolation. Termination assemblies for simplex input modules and termination
assemblies for simplex and dual output modules are single ended (non-isolated) with a
common return.
An expansion cable can be used to connect the processor base unit or an I/O base unit
to another I/O base unit. This is useful for to breaking long runs of interconnected
base units and provides some flexibility in the physical layout of a controller
installation, particularly if the controller is installed in a cabinet.