Spectracom VelaSync 1225, Руководство пользователя

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The alarm notification feature described below allows you to be notified of a potential
reception issue BEFORE the GNSS reference becomes invalid. This may be useful e.g.,
to notify system operators of a deteriorating signal reception before VelaSync loses the
GNSS reference.
Note that VelaSync itself has a pre-defined minimum number of satellites that must be
tracked in order for GNSS to be considered a valid reference. The minimum number of
satellites depends e.g., on your receiver mode, the GNSS signal reception in the area
where your antenna is located, and the type of receiver in your unit. In Stationary mode,
and for SAASM units, the minimum number of satellites is normally 4 (four). Hence, it
would be prudent to set the Minor Alarm Threshold to 8, and the Major Alarm
Threshold to 6.
Note: While GPS Notification Alarms can be used in Mobile GNSS
receiver mode , it is not advisable.
To determine how many satellites your VelaSync unit is currently receiving, navigate
to INTERFACES > REFERENCES: GNSS 0 . See also "Reviewing the GNSS Reference
Status" on page 124 .
To set the GPS Alarm Thresholds:
1.
Navigate to MANAGEMENT > OTHER: Notifications , and choose the GPS tab.
2. At the bottom of the window, locate the ALARM THRESHOLD panel:
3. In the Minimum Satellites fields enter the minimum number of satellites that
must be available before the alarm is triggered. The alarm will be triggered when
the number of satellites available is
BELOW this number.
4.
In the Duration Below Threshold (s) fields, enter the time in seconds that the
system must be below the threshold set in the Minimum Satellites field before
an alarm is triggered. The alarm will be triggered when this time is reached.
By default, this timeout value is set to 0 seconds: As soon as the receiver drops
below the minimum number of satellites, the associated alarm is triggered. A
4.4 Notifications
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4
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VelaSync User's Manual Rev. 3 171