Raymarine ST60 Tridata - Manual (Page 39)

Calibration 27
Chapter 4: Calibration
4.1 Introduction
The ST60 Tridata instrument is set up with factory-programmed default
settings, so in order to optimise the performance of the instrument on
board a particular vessel, the procedures in this Chapter must be carried
out immediately after the completion of installation and before the
equipment is used for navigational purposes.
Where practicable, the calibration procedures are presented
diagrammatically to show the sequence of key presses and the resulting
displays. Adjustment instructions are given as applicable.
Speed readings
One of the reasons for calibration is to ensure that the speed readings
displayed at the instrument are a true indication of the actual speed of the
vessel.
In User calibration - Speed, you can:
• Automatically set the displayed speed reading to be the same as the
Speed Over Ground (SOG) (if SOG data is available).
• Manually apply a calibration factor, to set the displayed speed to the
required value.
If neither of the above methods are suitable, you can carry out a speed
calibration run over a measured distance, to enable the instrument to
calculate the correct calibration factor. This is described as part of
Intermediate calibration.
EMC conformance
Always check the installation before going to sea to make sure that it is
not affected by radio transmissions, engine starting etc.
4.2 User calibration
The User calibration procedures enable you to:
• Set the required units for depth readings.
• Set the offset for depth readings, i.e. determine whether depth read-
ings are from the keel of the vessel or from the water line.
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