Siemens Simatic S7-300 CPU 31xC Series Installation And Operating Instructions Manual page 34

Configuring
4.6 Distribution of modules to several racks
Example: Full assembly using four racks
The figure shows the arrangement of modules in an S7-300 assembly on 4 racks.
4 4
3
2
1
The figure illustrates the following
(1)
(2)
(3)
(4)
(5)
(6)
4-10
PS
PS
PS
CPU
Rack 0 (central unit)
Rack 1 (expansion module)
Rack 2 (expansion module)
Rack 3 (expansion module)
The connecting cable 368
Restriction for CPU 31xC. When this CPU is used, do not insert SM 8 into Rack 4.
SM1 SM2 SM3 SM 4 SM5 SM6 SM7 SM8
IM
5
IM SM1 SM2 SM3 SM 4 SM5 SM6 SM7 SM8
5
IM SM1 SM2 SM3 SM 4 SM5 SM6 SM7 SM8
IM
5
SM1 SM2 SM3 SM4 SM5 SM6 SM7 SM8
IM
IM
S7-300, CPU 31xC and CPU 31x: Installation
Operating Instructions, Edition 08/2004, A5E00105492-05
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