Northrop Grumman Sperry Marine VisionMaster FT, Руководство пользователя

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Radar/Chart Radar User Guide Basic Operation of Radar
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Alternate Bow
If an alternate bow in use has been configured the system assumes that
there are two bows that may be used, the `normal bow’ at the front of the
ship and the ‘alternate bow’, usually at the rear of the ship.
The system should also be configured to include two CCRPs, one
applicable for each bow direction.
A switch may provide a discrete signal, which is also used by gyros and
speed logs to indicate whether the normal bow or alternate bow is acting as
the current bow of the ship.
If no external discrete signal is available an alternate bow menu can be
selected in the Configuration tool that enables the operator to tick an
Alternate Bow in Use check box. This is found in the Characteristics tab of
the Commissioning menu.
When alternate bow is enabled and the bow is switched from normal to
alternate the following changes take place:

All external sensors will update their signal to reflect the alternate
bow, i.e. the heading gyro will add 180º and speed logs will change
the sign of the speed value. If the system is using a stepper
interface (see `
Information on Sensor Inputs to the System ’ in
Chapter 1 ` Overview’ ) then the stepper may be re-aligned to reflect
the alternate bow heading. VM FT will not automatically adjust any
sensor input; however no inappropriate sensor alerts should be
generated as a result of alternate bow enablement.

Ownship symbol may change where the ‘bow’ of the outline is 180°
opposite of the heading being supplied.

All other synthetics (CCRP, radar positions, ownship vector origin)
are re-drawn to correctly reflect positions based on configured
offsets.

Corrections are performed to all sensor data (e.g. positions and
velocities) based on interpretation of configured positions.

Radar video is re-drawn such that it is centred on the correct
position origin, based on configured offsets (e.g. if the marker is a
heading marker in normal bow, it will be considered a stern marker
when switched to alternate bow).

Radars remain in transmit without adverse effects, other than
needing to rebuild trails or re-acquire targets.