Furuno DS-85, Руководство оператора, Страница: 23 / 44

1. OPERATION
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1.11.2 How to calibrate speed
Calibration of any speed log is necessary through the sea trials during the commissioning tests.
Fill in the calibration sheet at the back of this manual. Use the resultant data to calculate the speed
offset.
Note: Do not change the setting unnecessarily. Accuracy of speed measurement may be affected.
1. Press the MENU/ESC key to open the menu.
2. Select [3 SYSTEM], then press the ENT key.
3. Select [2 SPEED CAL], then press the ENT key to show the nu-
meric data input pop-up window.
4. Referring to "Numeric data input pop-up window" in
section 1.7.1, set the offset as calculated on the calibration
sheet, then press the
ENT key.
5. Press the DISP key to close the menu.
1.11.3 How to adjust tracking depth
Doppler shift measuring depth in the DS-85 is [2 m] at default. If the speed readout is unstable due
to air bubbles near the ship’s hull, increase or decrease the track depth to stabilize the readout.
Note 1: Incorrect adjustment of tracking depth can prevent detection of ship speed in some sea
areas.
Note 2: The IMO standard for STW (A.824(19)) requires that devices measuring STW perform in
water of depth greater than 3 m beneath the keel. So if the "track depth" is set higher than 3 m in
shallow water, this does not comply with the standard and the accuracy of true vector presentation
of the ARPA may be affected.
1. Press the MENU/ESC key to open the menu.
2. Select [3 SYSTEM], then press the ENT key.
3. Select [3 TRACK DEPTH], then press the ENT key to show the numeric
data input pop-up window.
4. Referring to "Numeric data input pop-up window" in section 1.7.1, set the
offset as required, then press the ENT key.
Note: The available setting range depends on the transducer settings, set at installation.
5. Press the DISP key to close the menu.
1.11.4 How to adjust echo criteria
Set how sensitively the equipment judges echo error.
1. Press the MENU/ESC key to open the menu.
2. Select [3 SYSTEM], then press the ENT key.
3. Select [4 ECHO CRITERIA], then press the ENT key to show the numeric data
input pop-up window.
4. Referring to "Numeric data input pop-up window" in section 1.7.1, set the criteria
level as required, then press the ENT key. The [9] setting provides the lowest er-
ror detection frequency.
5. Press the DISP key to close the menu.