Assembling and Installing Systems
A-28 AutomationSystem S7-400 Hardwareand Installation
A5E00850741-01
A.9.4 Sample of a Surge Protection Circuit for Networked S7-400
PLCs
Sample Circuit
The sample in the figure A-7 shows you how install an effective surge protectionfor
2 networked S7-400 PLCs:
CPUSV
10 mm2
PE
Switchgear cubicle1
L1L2L3NPE
Lightning-protection0, field side zone
Lightning-protectionzone 1
Lightning-protectionzone 2
SM
MPI CPUSV
10 mm2
PE
Switchgear cubicle 2
SM
MPI
Lightning-protectionzone 2
Figure A-7 SampleCircuitry for Networked S7-400 PLCs