Raymarine ST70 Instrument, User'S Reference Manual

Page: 26 / 48

20 ST70 Instrument User Reference Manual
If there is any inaccuracy after you have completed the Align Vane procedure, then:
1. At the
Wind transducer setup menu, select Vane
Adjust , to display the Vane Adjust screen.
2. Sail the boat directly into the wind, then use
<
and
>
to manually set the wind reading to zero.
3. Press
ENTER
to accept the value and return to
the Wind transducer setup menu.
4. Press
CANCEL
to return to the Transducers
found menu.
Calibrate wind speed
To set the correct apparent wind speed reading:
1. With the
Wind transducer setup menu
displayed, use
<
or
>
to scroll to Calibrate AWS ,
then press
ENTER
to display the Calibrate AWS
screen.
2. Use
<
or
>
to adjust the Calibration Factor so that
the AWS value in the information box is set to the
correct value.
3. Press
ENTER
to accept the value and return to
the Wind transducer setup menu.
4. Press
CANCEL
to return to the Transducers
found menu.
Speed calibration
The object of speed calibration is to ensure that the speed readings at the ST70
instruments are true indications of the boat speed, ideally over the speed range of the
vessel, i.e. from stationary to top speed.
In order to take into account the changes in water-flow characteristics across the hull,
for different speeds, it is advisable carry out speed calibration at as many speeds as
possible, up to the maximum of five, provided by ST70.
This is particularly
important for planing vessels .
The correct calibration at each speed is achieved by applying a calibration factor to
the indicated speed reading. The correct value for the calibration factor is obtained by
one of two methods:
•
If SOG information is available, you can use this as a reference, to enable you to
set the correct calibration factor.
• If SOG information is not available, you need to manually calculate and apply the
correct calibration factor.
In order to achieve accurate results, speed calibration must be carried out in
conditions of
zero tide and zero current .
Carry out the Start speed calibration procedure ( page 21 ) followed by the Set to SOG
or Manual calibration procedure, as required.
D10079-1
i
Manually adjust your vane offset.
Press ENTER to accept
Vane Adjust
15°
AWA 105° P
D10366-1
i
See Docs for Manual Calibration.
Calibrate AWS
AWS: 3.2 KTS
0.73
Calibration factor
AWS value
ess
81284_1.book Page 20 Friday, May 4, 2007 7:29 AM