Mechanical Protection Of Bus Cables - Siemens 6GK1 901-1GB01 System Manual

Installing network components in cabinets
3.3 Guidelines for setting up networked automation systems in buildings
Operation with 24 V DC
Numerous SIMATIC NET components require a voltage of 24 V DC as their operating
voltage or as auxiliary contact voltage. This power supply must meet the requirements of an
extralow voltage with reliable electrical isolation from the main power system, complying with
IEC 60950 or EN 60950 /18/.
Operation with line power
Components operated with line power must meet the requirements for protection against
electric shock as stipulated in EN 60950 /18/, EN 611312 /20/, EN 61010 /19/ or other
applicable product standards.
All the signals of the twistedpair port must meet the requirements of reliable electrical
isolation from the line power supply, complying with IEC 60950 or EN 60950 /18/.
Cabling components
Conductive cable path systems, barriers, and accessories must be included in the protective
measures preventing indirect contact (protection against illegal dangerous contact voltage).
Grounding conductors (PE) and equipotential bonding conductors must be installed
according to the requirements of systems in buildings complying with HD 384.4.41
(protection against electric shock) and HD 384.5.54 (grounding and grounding conductor).
The use of EN 501742 is recommended for the separation of low voltage cabling and IT
cabling.
The requirements of HD 384.4.47 S2 (application of measures for protection against electric
shock) and HD 384.4.482 S1 (selection of protective measures as a function of external
influences) and appropriate national or local regulations must be adhered to.
Safe initial state of the system in case of faults
Problems on communication connections must not be allowed to put system users at risk.
Cable or wire breaks must not lead to undefined statuses in the plant or system.
3.3.3

Mechanical protection of bus cables

Protection of electrical and optical bus cables
Mechanical protection is required to protect bus cables from breaks or mechanical damage.
Note
The measures described here for mechanical protection apply both to electrical and optical
cables.
80
Passive network components
System Manual, 02/2013, C79000-G8976-C282-01