Raymarine VCM100, Руководство по установке

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• Surrounding large objects, in the same horizontal plane, can
interfere with the radar signal and cause blind areas or shadow
sectors and false targets on the radar display (see below).
Do not mount the radar scanner so high that it is affected by the
pitching and rolling of the vessel.
Shadow areas and false echoes
Mount the radar scanner away from large structures or equipment,
such as engine stacks, searchlights, horns, or masts. These objects
may cause shadow areas and false echoes. For example, if you
mount the radar scanner on a mast, echoes from other targets may
be reflected from the mast. Wet sails may also cause shadow areas,
so radar performance may be reduced in the rain. It is particularly
important to avoid shadow areas near the bow. Raising or even
lowering the radar scanner may help to reduce these effects.
In shadow areas beyond the obstruction there will be a reduction of
the beam intensity. There may be a blind sector if the beam intensity
is not sufficient to obtain an echo from an object. This may occur
even at close range. For this reason the angular width and relative
bearing of any shadow area must be determined at installation.
You may be able to detect shadow areas or false echoes on your
multifunction display. For example, sea clutter can be used as a
good indicator of blind arcs. Dark sectors on the radar display
indicate possible shadowed areas. This information should be
posted near the display unit and operators must be alert for targets
in these blind areas.
Access
The radar scanner should be easily accessible to allow maintenance
to be carried out safely. Sufficient clearance must be allowed to fully
open the scanner unit for maintenance and service.
Mounting platform
The radar scanner must be mounted on a rigid and stable platform.
The platform must be capable of supporting the mass and inertia
of the radar scanner under seagoing conditions. The platform
should not twist (causing bearing errors) or be subject to excessive
vibration.
The mounting site must be clear of the following:
• Ropes.
• Moving rigging.
• Heat.
• Fumes.
• People.
Magnetic compass
Mount the radar scanner at least 1 m away from a magnetic
compass.
Multiple radar scanners
If two radar scanners are installed at different locations in a dual
radar system, care should be taken to allow for the difference in
position of the radars when switching between the two on your
multifunction display. This is especially noticeable at short ranges
on larger vessels.
Cables
• All cables should be adequately clamped and protected from
physical damage and exposure to heat. Avoid running cables
through bilges or doorways, or close to moving or hot objects.
• Where a cable passes through an exposed bulkhead or deckhead,
use a watertight feed-through.
Location and mounting
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