User's Manual

Galaxy Tracking Systems, L.L.C. VTU User’s Guide
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responds with one last IN SERVICE message to indicate the change in tracking status.
Commanding the VTU OUT OF SERVICE also stops tracking reports, however, in this
case, the VTU responds with a single OUT OF SERVICE message to report its change
in operating mode.
POLL REQUEST
The POLL REQUEST equivalent to issuing a ONE SHOT to every member a group
(fleet) of vehicles. Upon receipt of a POLL REQUEST each VTU will compare the
transmitted poll information to poll classes defined internally. If there is a match, the
VTU will transmit an IN SERVICE message at the frequency and in the time slot
specified in the matching poll class. Poll classes are factory configured to allow low
priority status reporting for large groups of related vehicles.
Poll responses are low priority. If the VTU is responding to a command or a self-
activation the poll request is ignored. A scheduled poll response is automatically
canceled if the VTU receives a command packet or self-activates. Polls do not extend
beyond the end of the 30-second cycle in which the poll was requested. If the VTU
schedules a poll response, it will ignore any new poll packets until the scheduled poll
response completes.
SELF ACTIVATION (SOS)
A vehicle (VTU) does not report its position on a regular basis until it is commanded to
ACTIVATE by the command center. In emergency situations, however, the VTU can
request to begin regular position reporting in order to be tracked by “SELF
ACTIVATING”.
The conditions that can result in SELF-ACTIVATIONS are SOS, request for roadside
assistance, unauthorized movement and vehicle alarm. SOS and the roadside
assistance requests are initiated when the operator depresses a switch (if equipped
with the switch box option). If the operator has armed the VTU motion sensor (included
in the switch box option), movement of the vehicle beyond a few hundred feet or at
speeds in excess of 20 KPH will trigger a SELF-ACTIVATION.
If the vehicle has an alarm system with an appropriate output signal, it can be
connected to the VTU. Triggering the vehicle alarm will then also generate a SELF-
ACTIVATION.
SELF ACTIVATION ACKNOWLEDGEMENT
Once a SELF-ACTIVATION has occurred, the corresponding status LED on the switch
box will blink until the SELF-ACTIVATION has been acknowledged by the command
center, at which point the LED will glow steadily.
RESET ALARMS