Calibrating the sensors, Installation – Raymarine 465 User Manual
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Installation
Note –
Press firmly when inserting the power cable and transducer cable to
ensure a tight seal.
8.
When you press the
PWR
button, the display unit should turn on. If
the unit will not turn on and you suspect that you may have reversed
the power connections, check the DC power lines all the way back to
the battery. If the polarity is not correct, reconnect the leads properly
and try again.
Calibrating the Sensors
The transducer most often used with this unit includes sensors for boat
speed and water temperature. These sensors are normally very accurate,
but you may want to calibrate them.
The speed indication on your FishFinder is usually very accurate.
However, there are some special cases where the speed reading may be
high or low. This means that the speed of the water past the transducer
may not be the same speed that your boat moves through the water. The
hull of the boat may have a shape which channels water past the
transducer at a speed which is faster or slower than normal.
1.
To calibrate the speed sensor, set up a course between two known
points. As markers you can use buoys, range markers, or landmarks.
Measure the time the boat takes to cover a known distance.
2.
You may also use locations indicated by a G.P.S. or Loran unit. (If
you choose this method, remember that these devices measure
“speed over ground” or “speed over the bottom.” Tides, currents, or
winds can create a difference between the FishFinder’s “speed
through water” measurement and the boat’s “speed over ground.”
Before calibrating using a G.P.S. or Loran unit, wait for still water or
slack tide conditions.
3.
If the display unit is reading high or low, you can correct for this using
the entry for “Speed Cal.” (To reach Speed Cal, go to the System
Setup Menu. This is described in Section 4.) The entry for Speed
Cal is a percentage. An entry of “100” equals 100%, meaning that
there is no correction. If the display unit is producing a
low
reading,
use a
higher
value for Speed Cal. If the display unit is reading
high
,