Example: Surge Protection Circuit For Networked S7-300 Plcs - Siemens Simatic S7-300 CPU 31xC Series Installation And Operating Instructions Manual

Appendix
A.3 Lightning and surge voltage protection
A.3.5

Example: Surge protection circuit for networked S7-300 PLCs

The sample in the figure below shows you how install an effective surge protection for two
networked S7-300 PLCs:
L1 L3 PE
L2 N
1
PE
10 mm
A-26
Lightning protection zone 0, field side
Lightning protection zone 1
2
Cabinet 1
Lightning protection zone 1
SV CPU SM
4
MPI
4
3 5
2
2
Lightning protection zone 1
SV CPU
MPI
2
PE 10 mm
6
3
Operating Instructions, Edition 08/2004, A5E00105492-05
Cabinet 1
SM
4
4
5
6
3
7
S7-300, CPU 31xC and CPU 31x: Installation