Installing the S7-400

2.3Segmented 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 segmented 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 segmented 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.

1

 

 

 

 

 

 

 

 

 

11

 

 

 

 

 

 

 

SEG1

 

 

 

 

 

 

 

SEG2

 

 

 

 

 

 

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

SEG1

SEG1

SEG1

SEG1

SEG1

SEG1

SEG1

SEG1

SEG1

SEG1

SEG2

SEG2

SEG2

SEG2

SEG2

SEG2

SEG2

SEG2

I/O bus Segment 1

I/O bus Segment 2

Communication bus

2-8

Automation System S7-400

Hardware and Installation

 

A5E00850741-01

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Image 24
Siemens S7-400 installation manual Segmented CR, Properties