10. User Charts; Introduction; Objects Of User Charts - Furuno FMD-3100 Operator's Manual

10. USER CHARTS

10.1

Introduction

User charts are overlays that the user creates to indicate safety-related objects and
areas. They can be displayed on both the radar overlay and the electronic chart.
These charts are intended for pointing out safety-related items like position of import-
ant navigation marks, safe area for the ship, etc. User charts areas can be used to ac-
tivate alerts and indications based on user-defined danger symbols, lines and areas.
When route or own ship estimated position is going to cross a user chart symbol, line
or area that is defined as a dangerous one, an alert or indication is generated by the
system. See the chapter on chart alerts.
A user chart consists of various objects (points, lines, text, symbols, etc.). The maxi-
mum number of points per user chart is 200 (a circle is one point, a rectangle is four
points). You may link up to five user charts to a route, for a max. of 1,000 user chart
points per route.
The user chart is displayed on the radar overlay and its position and shape is based
on the ship's actual position. When own ship is moving in the area covered by the user
chart, the elements of the user chart are superimposed on the radar, with a maximum
of 60 of the nearest elements displayed.
10.1.1

Objects of user charts

Below is a description of the objects used in a user chart.
• Tidal: There are two types of tidals, current and predicted.
• Line: You can define four different types of lines. Lines can be used in chart alert
calculation and/or display on the radar:
• Navigation lines: Displayed on both the radar overlay and the ECDIS display.
Navigation lines are reference lines for coast line.
• Coast line: Displayed on both the ECDIS and radar overlays. Coastal line is usu-
ally a well-defined (by chart digitizer) multi-segment line showing the coastline.
The user is able to create this type of line in case there is no suitable chart avail-
able over desired area in S57 format.
• Depth contour: Displayed on both the ECDIS and radar overlay. Depth line
shows the chosen depth levels. The user is able to create this type of line in case
there is no suitable chart available over desired area in S57 format.
• Route line: Displayed on both the radar overlay and the ECDIS display. Route
lines are zones for anchoring, traffic separation lines, etc.
• Clearing line: A clearing line is used to define a line which a vessel can sail to avoid
navigational hazards. A clearing line can be of the NMT (Not More Than) or NLT
(Not Less Than) type. Displayed on the ECDIS display only.
• Area: The operator can define closed areas, which the system can use to detect
safe water areas. If route or estimated ship position is going to cross the area, the
system generates a warning to the user. These areas can be used to specify safe
10-1