Sperry Marine Visionmaster FT ECDIS, Руководство пользователя

Страница: 182 / 531

Charts ECDIS User Guide
4-50 65900012

VPF (Vector Product Format)
25

World Map
26
(ENC).
C-Map and SevenCs presentation libraries are supported.
Official and Unofficial Chart Data
Chart databases may be classified as Official or Unofficial chart data.
Official chart data is known as Electronic Navigational Chart (ENC) data. All
official ENC chart data must comply with data standards set by members of
the International Hydrographic Organisation (IHO) and published in their
document S-57, Edition 3.
An unofficial chart database is data which does not comply with the S-57
Edition 3 document (e.g. SevenCs World Map).
An Unofficial Data permanent prompt is displayed whenever chart data
from an unofficial source is displayed (for example, SevenCs World Map
charts). Unofficial data is not certified for safe navigational and the operator
should refer to paper charts for unofficial data regions.
The unofficial data prompts are as follows:
•
Unofficial Data in Primary Display
•
Unofficial Data in Secondary Display
SevenCs supports both official and unofficial data. The official boundary
line is always displayed to distinguish official and unofficial data, unless it
has been explicitly disabled by the operator using the `Official Boundary'
custom chart setting for the SevenCs engine, see Settings.
Certain C-Map chart databases include a combination of official and
unofficial chart data (see C-Map chart database descriptions above). While
all types are used for safety checking, only official ENC data can satisfy the
ECDIS requirements that may in some cases allow a vessel to navigate
without reliance on up-to-date paper charts.
Even when official ENC data is used the operator should be mindful
of the quality of data, and is encouraged to view the data quality
symbol at appropriate intervals and understand the meaning of these
symbols.
25
As used by the Digital Nautical Chart (DNC) produced by the National Geospatial
Intelligence Agency (NGA). A `DNC data displayed' prompt appears when using these charts.
26
The World Map database is delivered with the SevenCs Chart Engine and is based on the
NGA World Vector Shoreline 1:250,000 charts. The structure of the data is defined by the IHO
S-57 specification. Note that this database is only suitable for small scale viewing. It is not
official format and therefore not safety checked.