Outdoor Cable Routing - Siemens SIMATIC S7-300 Hardware And Installation Manual

12.2.5 Outdoor cable routing

Rules for EMC compatible cable routing
The same EMC compatibility rules apply both for indoor and outdoor routing of
cables. The following also applies:
• Running cables on metal cable trays.
• Electrical connection of the joints of cable trays/ducts.
• Ground the cable carriers.
• If necessary, provide adequate equipotential bonding between connected
devices.
• Take the necessary (internal and external) lightning protection and grounding
measures in as far as they are applicable to your particular application.
Rules for Lightning Protection Outside Buildings
Run your cables either:
• in metal conduits grounded at both ends, or
• in concrete cable ducts with continuous end-to-end armoring.
Overvoltage protection equipment
An individual appraisal of the entire plant is necessary before any lightning
protection measures are taken.
Additional information on lightning protection ...
can be found in the Lightning and surge voltage protection section.
S7-300 Programmable Controller Hardware and Installation
A5E00105492-02
Appendix
12-17