Kongsberg Seatex Seapath 200, Installation Manual

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Seatex Seapath 200 Installation Manual, rev. 13 Installation
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possible, one reading from both systems should be done at least every 30 seconds for a
minimum of two full hours.
The long calibration time is necessary in order to cancel out errors in the Seapath
measurements caused by multipath effects, which may be particularly pronounced in the static
conditions of a harbour area.
Before calibration, measure the baseline length between the GPS antennas to within a
tolerance of one centimetre or better. If the standard antenna bracket is used, the baseline is
2.500 metres. Enter the measured baseline length into the Processing Unit by using the SCC
software.
The observations from each of the two different systems are then averaged and the offset
between the two systems (reference minus Seapath reading) is the Seapath heading offset. If
heading offset was not entered as zero in the SCC software on beforehand, the calibration
value should be added to the existing offset value.
The baseline length and height difference should be determined within an accuracy of 10
centimetres in height difference and 1 mm in baseline length. These values should be entered
into the Seapath through the SCC software. By using the calibration wizard in the SCC
software the baseline length and height difference are calculated automatically.
Example:
If the heading measured by the reference system is found to be 32.1 degrees and the Seapath
heading after the calibration has been determined to be 15.3 degrees, the Seapath heading
offset to be input in SCC is the value 16.8 (32.1 - 15.3).
3.4.4.2 Typical calibration procedure
This is an example on how to perform a GPS antenna calibration. Proceed as follows:
1.
Start up the SCC software and establish contact with the Processing Unit. When contact is
established, enter the Configuration Folder List, select
Sensor \ GPS \ Antenna
Configuration
.
2.
Before editing parameter values belonging to a connected Seapath, it is recommended to
first perform an upload from the Seapath. See chapter 8.4.6.2, "Upload".