POS MV V5 Installation and Operation Guide
Fault
Identification
Copyright © Applanix Corporation, 2017
9-17
GNSS
If proper operation is not restored within a minute, select
Tools,
Reset GNSS
from the controller menu bar. The GNSS receiver is
reset to the factory defaults. This action takes a couple of minutes.
Also. if the auto configuration feature is enabled, the receiver will
assume an appropriate POS configuration.
Finally, if all else fails, cycle the PCS power (off and on) to provide a
hard reset of the GNSS receiver. Refer to the Power-On and Power-
Off procedures on pages 4-1 and 4-27 respectively.
GAMS
The GAMS subsystem can experience a permanent loss of satellites,
or a communication failure between the GNSS receiver and the PCS.
Permanent Loss of Satellites
The
GAMS Solution
window provides information on satellites being
tracked and the status of GAMS; select
View, GAMS Solution
to
view this window.
GAMS may experience periodic GNSS dropouts caused, for example,
by an antenna obstruction. During these dropouts, GAMS is unable to
compute a heading solution and the controller
Status
pane indicates
Not ready
in the
GAMS
field.
However, if a GAMS dropout occurs and persists without any
apparent antenna obstruction, one of the following problems may
exist:
•
A loss of GNSS receiver configuration
•
A failure in the GNSS antenna
•
A failure in the GNSS antenna cable
•
A failure in the GNSS receiver
The above diagnosis assumes that the PCS continues to receive
messages from the secondary GNSS receiver. Select
View, GAMS
Solution
to see the GAMS status.
GAMS Ambiguity Resolution Failures
If there is a GAMS ambiguity resolution failure, the controller
Status
pane indicates
Not ready
in the
GAMS
field. The same status is
indicated when there is satellite signal loss due to an antenna
obstruction.
The POS MV
Message Log
window specifically indicates GAMS
ambiguity resolution failures; see Figure 64 on page 9-9.