Tritech Intelligent Gyro Compass, Руководство по эксплуатации продукта

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Tritech International Ltd Intelligent Gyro Compass
8.7.3 Heave Acceleration Data Checks
In certain modes, the iGC transmits the raw heave acceleration from its ‘z-axis’ accelerometer sensor.
This can be used for heave compensation systems or for other navigation / survey purposes.
If the selected operating mode supports this output, check that with the system at rest the output is
nominally 1.00g acceleration or -9.81 ms
-2 depending on the selected telegram format. By moving the
iGC up and down, a change to the heave acceleration should be seen. Note that certain telegram
formats show the acceleration due to gravity, and others remove this offset prior to transmission.
Note that this output is referenced to the vertical iGC axis, not to ‘earth’ frame. It follows that the output
at pitch and roll angles other than 0º will give a heave acceleration figure approximately equal to the
measured Heave multiplied by the combined cosine of the pitch and roll angles.
8.7.4 Water Ingress Alarm Checks
Inside the iGC there is a water ingress detector, comprising two gold pins that extend from the
interface PCB down to the lowest point inside the iGC housing. See photograph below for details:
Certain output formats support the transmission of a Water ingress alarm. If used in one of these
modes, during checks the water ingress signal should be ‘Dry’. If not, the reasons for this should be
investigated before operating the system underwater.
When the interface PCB detects a water ingress condition, the Red LED (shown in the photograph)
illuminates. The water ingress sensor function can be checked by placing a wet finger (or a resistance
less than 300kohm) across the sensor pins.
8.7.5 Other Data Checks
In iGC Proprietary data formats, additional data such as iGC temperature, serial number etc. are
available. These can be checked using the iGC Navigation Software.
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