User's Manual

GlobalTrak ™ GT Lite Operation and Maintenance Manual
Door Sensor (optional)
The door sensor is a digital input to the device. If the input is open or floating, the door state
is reported to be open. If the input is connected to ground, the door state is reported closed.
The sensor output is constantly monitored and edge triggered, even when the GT Lite is in its
lowest power state. Following first indication of a possible change of state, the sensor is
sampled for an additional number of seconds, and an event is declared only after all
consecutive readings indicate such. For a door open or closed event, the GT Lite immediately
generates a message and sends to the IMB. The door sensor is immediately re-armed after
any event.
The sensor can be enabled or disabled over-the-air through the GSM network or locally.
The door sensor can be either externally wired or mounted internal to the GT Lite. The
external sensor can be any contact closure switch between the input and ground. The
internal door sensor is a reed-based, magnetic proximity sensor, implemented as a single
pole, single throw (SPST) normally open contact switch. Circuit is closed when the actuator is
within 1.5”. The circuit is open when the actuator is outside of 1.7”. This sensor is placed at
the edge of the enclosure for applications where GT Lite is mounted on, or next to, a door.
Temperature Sensor
The sensor range is from -40°C to +85°C, with accuracy within <1°C across this range.
The sensor output is be sampled by the low power controller at a rate of 1 reading per
second, even when the GT Lite is in its lowest power state. The measured value is compared
against a stored upper and lower threshold, and when either is crossed, an event message is
to be immediately generated and sent to the IMB. The sensor is re-armed after the sensor
level returns from the alarm state. At the point where the sensor level crosses the threshold
back to a typical level the sensor alarm is once again active.
All thresholds are user programmable, changeable over-the-air through the GSM network or
locally. Also the thresholds can be disabled, such that no event message is generated.
Mount Sensor
The sensor is a reed-based, magnetic proximity sensor, implemented as a single pole, single
throw (SPST) normally open contact switch. Circuit is closed when the actuator is within 1.5”.
The circuit is open when the actuator is outside of 1.7”.
The sensor output is constantly monitored and edge triggered, even when the GT Lite is in its
lowest power state. Following first indication of a possible change of state, the sensor is
sampled for an additional number of seconds, and an event is declared only after all
consecutive readings indicate such. For any change in mount status, the GT Lite immediately
generates a message and sends to the IMB. The mount sensor is immediately re-armed after
any event.
The sensor can be enabled or disabled over-the-air through the GSM network or locally.
The location of the magnetic sensor located inside the GT Lite cover is marked. The actuator
is located in line with the sensor making on the GT Lite cover. The actuator and GT Lite
enclosure are to be mounted separately so if the GT Lite is removed, the actuator stays.
Prepared: R. Straz Date: July 25, 2007 Page 17 of
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