Electromagnetic Compatibility Of Fiberoptic Cables - Siemens 6GK1 901-1GB01 System Manual

Installing network components in cabinets
3.3 Guidelines for setting up networked automation systems in buildings
Redundant bus cables
The installation of redundant bus cables involves special requirements. Redundant cables
should always be installed on separate cable racks to avoid simultaneous damage by the
same event.
Install bus cables separately
To prevent accidental damage to bus cables, they should be clearly visible and should be
separate from all other wiring and cables. To improve EMC, it is often advisable to install the
bus cables in a separate cable channel or in conductive metal tubes. Such measures also
make it easier to localize a faulty cable.
3.3.4

Electromagnetic compatibility of fiberoptic cables

Fiberoptic cables
For communications between buildings and/or external facilities, the use of fiberoptic cables
is generally recommended. Due to the optical transmission principle, fiberoptic cables are
not affected by electromagnetic interference. Measures for equipotential bonding and for
overvoltage protection are unnecessary with fiberoptic cables.
Note
Fiberoptic cables are ideally suited for connections in areas with high EMI levels.
Remember, however, that bus components operating on an electrical basis such as OLMs,
OSMs etc. may require additional noise protection measures if they are operated in such
areas. These must be protected against unacceptable interference using the measures
already mentioned such as shielding, grounding, minimum clearance to sources of
interference etc.
82
Passive network components
System Manual, 02/2013, C79000-G8976-C282-01