Warning Overvoltage Protection; Installing And Commissioning The Cm 1243-5 - Siemens CM 1243-5 Operating Instructions Manual

3.1

Warning overvoltage protection

CAUTION
Protection of the external 24 VDC power supply
If power is supplied to the module over longer 24 V power cables or networks, the coupling
in of strong electromagnetic pulses onto the power supply cables is possible. This can be
caused, for example by lightning strikes or switching of higher loads.
The connector of the external 24 VDC power supply is not protected from strong
electromagnetic pulses. To protect it, an external overvoltage protection module is
necessary. A suitable device is, for example, the Dehn Blitzductor BVT AD 24V type no.
918 402 or comparable protective element.
Manufacturer:
DEHN + SÖHNE GmbH + Co. KG, Hans-Dehn-Str. 1, PO box 1640, D-92306 Neumarkt
3.2

Installing and commissioning the CM 1243-5

Prior to installation and commissioning
Read the system manual "S7-1200 Programmable Controller"
Prior to installation, connecting up and commissioning, read the relevant sections in the
system manual "S7-1200 Programmable Controller" (refer to the documentation in the
Appendix).
When installing and connecting up, keep to the procedures described in the system manual
"S7-1200 Programmable Controller".
Make sure that the power supply is turned off when installing/uninstalling the devices.
Configuration
One requirement for the commissioning of the CP is the completeness of the STEP 7 project
data. You should also read the section "Configuration and programming (Page 25)".
CM 1243-5
Operating Instructions, 04/2011, C79000-G8976-C246-01
WARNING
Installing, connecting up and commissioning
3.1 Warning overvoltage protection
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