Network Router User Manual

Installing the S7-400

2-8

Automation System S7-400 Hardware and Installation

A5E00850741-01

2.3 Segmented CR

Properties

The “segmented” characteristic relates to the configuration of the CR. In the

(non-segmented) CR the I/O bus is continuous and interconnects all 18 or 9 slots;

in the segmented CR, however, the I/O bus consists of two I/O bus segments.

A s egmented CR has the following important characteristics:

• The communication bus is continuous (global), whilst the I/O bus is divided into

two I/O bus segments of 10 and 8 slots respectively.

• One CPU can be inserted per local bus segment.

• The two CPUs in a segmented CR may be in different operating states.

• The two CPUs can communicate with each other via the communication bus.

• All the modules inserted in a s egmented CR are powered by the power supply

module at slot 1.

• Both segments have a common backup battery.

The following figure shows a segmented CR with divided I/O bus and continuous

communication bus.

I/O bus

Segment 1

I/O bus

Segment 2

SEG1 SEG1 SEG1 SEG1 SEG1 SEG1 SEG1 SEG1 SEG1 SEG1 SEG2 SEG2 SEG2 SEG2 SEG2 SEG2 SEG2 SEG2

1 2 3 4 5 6 7 8 9101112131415161718

SEG1

SEG2

Communication bus