Applanix POS MV V5 Installation And Operation Manual page 204

POS MV V5 Installation and Operation Guide
Fault
Identification
GAMS Not Ready
After the POS MV system is installed, the GNSS Azimuth Measurement Subsystem (GAMS) requires
calibration. Refer to the Initial GNSS Configuration description starting on page 4-21 for instructions.
Once GAMS is calibrated, it will initialize itself and deliver heading measurements automatically each time
the system is powered-on and enters the navigate mode. Depending on the availability of satellites, the
GAMS Initialization process may take up to five minutes.
If there is a temporary loss of satellites, e.g. caused by a signal obstruction, the GAMS Status may show
Not Ready for brief periods. However, if GAMS Status shows Not Ready for an extended period after
power-on, or if it transitions from Online to Not Ready and remains there, take the following steps to
determine the cause.
1. Select View, GAMS Solution from controller menu bar. In GAMS Solution window, check
number of SVs tracked and value displayed for PDOP. GAMS must track five SVs minimum and
have PDOP value <3 before it can solve ambiguities. Wait for satellite constellation to improve or
move to a location that has better satellite visibility.
2. If number of SVs tracked does not increase or if PDOP remains too high, problem may be GNSS
antenna installation. Examine GNSS antennas, cables and connectors for damage or
degradation.
3. GAMS may experience problems caused by invalid calibration or excessive vibration in the
antennas. Check antenna installation and ensure antennas are rigid relative to each other and
relative to IMU.
Serial Communications Problem
A serial communications problem may occur on any of the user configurable COM ports. Use the
following steps to determine the nature of the problem.
1. Select Settings, Input/Output Ports from controller menu bar. Verify parameter settings; see
Figure 76 and the COM Ports description starting on page 3-1.
2. Verify serial port connection.
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