Sperry Marine Visionmaster FT ECDIS, User Manual

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ECDIS User Guide Basic Operation of ECDIS
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True Motion Limits
When a chart window is first displayed, the TM limits for that chart window
is centred with a default maximum width and height of approximately 90%
of the chart window’s width and height.
When own ship's CCRP reaches the edge of the TM limits box and TM
reset limits are enabled, own ship is repositioned to the opposite edge of
the box such that a line drawn from own ship in the direction of the current
course passes through the centre of the box, see Motion Modes.
Own ship may be moved outside the TM limits box when TM reset limits
are disabled (either in panning mode, or when Goto.. location values are
applied). In this case, the message
TM Limits Off is displayed in the
Motion Mode field. To move own ship back to the centre of the TM limits
box left click on the Motion Mode button, TM limits are re-enabled to the
display.
Displaying the TM Limits
The effective ship box is hidden on the chart display.
To temporarily display the box right click on the Motion
Mode button and select
Show TM Limits , the effective
ship box is displayed for about three seconds.
Setting the TM Limits
The size and location of the TM limits can be set
independently on primary and secondary chart
displays.
To set the TM limits do the following:
1. Right click on the Motion mode button and select Set TM Limits
from the drop down list. The current TM limits appear on the chart
display with a movable square box in hatched line, representing the
minimum size of the TM limits. See Figure below.
2. With the cursor inside the box left click to specify the centre of the
TM limits box. You can then re-size the box by moving the trackball
across or down.
3. When the required parameters are displayed left click. The TM
limits are re-sized and own ship is moved to the centre of the box.
4. To change the TM limits in a secondary chart window select Set
TM Limits , move the screen cursor inside the secondary window
TM box and repeat steps 2 and 3 above.