Teletrac Prism TM, Информация по установке

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Teletrac, Inc. - Prism TM Information and Installation Guide
1622-0300 B1 3/18/04 25
In addition, since the GPS Receiver is locating itself continually, the
Prism TM would send a
message with the exact time of the event happening. This would eliminate the 15-minute error
factor in Fleet Director. There are a maximum of three (3) zones that can be configured into each
unit.
A zone can either be a circle with a center and radius or a
square with a center and distance to the edge. In order to
determine a zone, you will need to find the Latitude and
Longitude for the center of the zone. Next, determine the
distance, in meters, from the center of the zone to its edge.
Next, you will need to determine the Hysteresis. This is a
gray area outside and inside the edges of the zone that will
account for jitter in the locations. You will be able to select
the size of the Hysteresis from 0 meters to 250 meters. Within the Hysteresis, you will not be
considered inside or outside the zone. The vehicle will effectively be in “No Mans Land”. The
Hysteresis can also be turned off so that the actual edges of the zone are used for the exception.
Speed Threshold
A natural spin-off from time and distance is speed. The Prism TM can detect its own speed more
accurately then Fleet Director (+/- 1 mph accuracy). Because of this, the Prism TM can detect
speed violations thus alerting dispatch of possible violations or exception condition.
Thresholds can be set in the Prism TM to trigger warning messages when the
vehicle goes above a specific speed. Even more, a timer can be set to alert
dispatch only if the threshold is detected for a required length of time. In order
for the messages to be sent, the speed must pass through the set speed.
Dynamic Power Management
By default, the Prism TM is programmed with a robust interactive power management routine.
This routine forces the Prism TM to periodically shut down its internal high current components
(the GPRS modem and the GPS receiver) while the vehicle ignition is OFF. This feature will
decrease the
Prism TM current consumption significantly. While these components are shut
down, the workstation is incapable of setting up a communications link with the Prism TM for the
requesting of location or the sending of messages. While the Prism TM is asleep the ability to
send messages from the MDT and do vehicle status changes (in motions, input change, etc.) will
not be prevented but may suffer a slight delay caused by the
Prism TM waking up.
To the customer (and the system) it appears as though the
Prism TM is out of the coverage area
while the Prism TM is asleep. To reduce the possible confusion as to if the unit is asleep or out
of coverage, when the unit goes to sleep it will send a message prior to shutting down to indicate
the shut down and to inform how long the unit will be asleep. Otherwise, if no message is
captured then the unit is out of the coverage area.
When the unit does go to sleep, it will check it’s operating conditions to see if it
is allowed to go to sleep then, it will start a timer, if the conditions remain the
same at the end of the timer then the unit will go to sleep. The unit will send a
message to the workstations saying that in X minutes it will be going to sleep
hys·ter·e·sis (h s t -r s s)
n., pl. hys·ter·e·ses (-s z.)
The lagging of an effect behind
its cause, as when the change in
magnetism of a body lags behind
changes in the magnetic field
Note: Unit must have
the following conditions
in order to go to sleep:
Ignition Off
Not moving
Note: The actual speed
must pass through the set
speed in order to trigger
the message.