Sperry Marine NAVIKNOT 600 SE, Руководство по эксплуатации, установке и обслуживанию

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NAVIKNOT 600 SE 056349/C
Sensor Sensitivity Setting 7-1
Chapter 7: EM Sensor Calibration
Once the NAVIKNOT 600 SE system has been installed and the basic
configuration carried out, the EM sensor must be calibrated to make
sure that the system’s water speed and distance outputs meet the speci-
fied accuracy.
7.1 Sensor Sensitivity Setting
Upon installation or exchange of the EM sensor, the sensor’s sensitivity
value must be stored in the NAVIKNOT 600 SE electronics unit.
Sensitivity is a characteristic property of the individual sensor installed
and is noted on a label attached to the sensor. It is also recorded in the
delivery documents for the given sensor.
The sensitivity value is a dimensionless number for the ratio between
the sensor’s return signal and the nominal standard of 180
μ
VAC/kn.
Typical values for EM sensors range from 0.7 to 1.14.
Figure 7-1:
effect of the
sensor sensitivity
raw speed data (input)
sensitivity-corrected
speed data (output)
0.8
1.0
1.25
Note When checking the effect of the sensitivity setting, bear in mind that the
value does not equal the gain applied but, rather, its reciprocal. Thus, for
example, a sensitivity value of 0.8 multiplies the raw speed by 1.25, while
a value of 1.25 multiplies it by 0.8.
To set the sensitivity value:
1. Go to page 2 of the Serv-
ice Setup and select the
Sensor Sensitivity sub-
menu.
2. With the Up/Down and
Right/Left keys, set the
sensitivity as required.
3. press ENTER to store the
value and exit the sub-
menu.
SERVICE SETUP Page 2
SENSOR SENSITIVITY
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