Simrad SC90, Руководство по установке

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419050/B
257
Basic cable requirements
It is very important that all systems cables are installed correctly. All cables must be
properly supported and protected, and all relevant precautions must be made to prevent
unwanted noise.
Topics
Cable trays, page 257
Radio frequency interference, page 258
Physical protection of cables, page 258
Grounding of system cables, page 259
Cable connections and terminations, page 259
Cable identification, page 259
Cable glands and termination procedures, page 260
Cable trays
All permanently installed cables associated with the system must be supported and
protected along their entire lengths using conduits and/or cable trays.
The only exception to this rule is over the final short distance (maximum. 0.5 meters) as
the cables run into the cabinets/units to which they are connected. These short service
loops are to allow the cabinets to move on their shock mounts, and to allow maintenance
and repair.
1 Wherever possible, cable trays must be straight, accessible and placed so as to
avoid possible contamination by condensation and dripping liquids (oil, etc.).
They must be installed away from sources of heat, and must be protected against
physical damage. Suitable shields must be provided where cables are installed
in the vicinity of heat sources.
2 Unless it is absolutely unavoidable, cables should not be installed across the vessel's
expansion joints. If the situation is unavoidable, a loop of cable having a length
proportional to the possible expansion of the joint must be provided. The minimum
internal radius of the loop must be at least twelve times the external diameter of
the cable.
3 Where a service requires duplicate supply lines, the cables must follow separate
paths through the vessel whenever possible.
4 Signal cables must not be installed in the same cable tray or conduit as high-power
cables.
5 Cables containing insulation materials with different maximum-rated conductor
temperatures should not be bunched together (that is, in a common clip, gland,
Cable layout and interconnections