Operating Instructions and Installation Instructions

NAVMAN 8120/8084 Installation and Operation Manual88
19-13 Setup > Calibrate
Press
MENU
twice, then select Calibrate:
Speed
This calibrates the speed from a paddlewheel
sensor connected to the Instrument.
Calibration may be required because different
hull shapes have different flow characteristics.
Obtain an accurate measurement of the
boat’s speed from a GPS receiver; or by
following another boat travelling at a known
speed; or by making a timed run over a
known distance.
Note: for accurate calibration:
• The speed from a GPS receiver should be
greater than 5 knots.
• The speed from another paddlewheel
transducer should be between 5 and 20
knots.
• Best results are achieved in calm
conditions where there is minimal current
(best at high or low tide).
Calibrating speed:
1 Travel at a constant, known speed.
2 In the Calibrate menu, select Speed.
3 Press
or to change the displayed
speed to the true value.
4 Press
ENTER
.
Speed filter
Waves and wind cause the boat speed from
the paddlewheel transducer to fluctuate
slightly. To give stable readings, the
Instrument calculates these values by taking
several measurements and averaging them.
Set the Speed filter to the lowest value which
gives stable readings. The range is 1 to 30
seconds or Off (0).
Temperature
The factory settings should be sufficiently
accurate for normal usage. To calibrate the
temperature readout, first measure the water
temperature with a thermometer known to
be accurate.
Use the cursor keys to display the
temperature readout box, then increase or
decrease the value to match the measured
temperature. The temperature can be set
from 32° to 99.9°F (0° to 37.7°C) with a
resolution of 0.1° unit.
To change the units between °F (Fahrenheit)
or °C (Celsius), see section 19-11.
NavBus
NavBus is the preferred method for
connecting the Instrument to other NAVMAN
instruments. Select this if the instruments are
connected using NavBus.
NavBus Group
Use this when a group of NAVMAN
instruments are connected together using
NavBus, to specify a group of instruments
for backlighting, if required. Then, if the
backlight setting on one instrument in the
group is adjusted, the other instruments
change automatically. Otherwise, select 0.
See section 20-11.