Intruder Detection - Interlogix FlexZone Series Product Manual

Chapter 3: Calibration and setup
by the initial contact with the fence, which is followed by a series of peaks and
valleys resulting from the continued presence and changing stresses on the
fence. Environmental activity is generally of longer duration, lower magnitude,
and has more gradual increases and decreases. The FlexZone processor
analyzes the received signals from the sensor cables and records separate
Events independently. As a result, the processor can record and report multiple
disturbances over the length of the sensor cable.
FlexZone's minimum target resolution for perfectly synchronized
Note:
disturbances is 24 m.
The Threshold is the received signal strength at which an Event is added to the
Event Count. It is measured in dB and can be set globally for the full length of
detecting cable. An independent Threshold can also be set for each defined
cable segment.
•
When the rising edge of the received signal from the sensor cable exceeds
the Threshold, the Event Count is incremented by one.
•
The next Event will not be recorded until the period specified by the Event
Window has lapsed.
•
Once the Event Window has lapsed, when the rising edge of the received
signal from the sensor cable exceeds the Threshold, the Event Count is
incremented by one.
•
If the received signal remains above the Threshold for the period specified by
the Event Window (i.e., a climbing intrusion) the Event Count is incremented
by one.
•
Each time the Event Count is incremented, the Alarm Window time is reset to
zero.
•
When the value specified as the Event Count is reached within the Alarm
Window time, a sensor alarm is triggered, and the Event Count is reset to
zero.
•
If the Alarm Window Time expires the Event Count is reset to zero without
triggering an alarm.

Intruder detection

The FlexZone sensor guards against three intrusion scenarios:
•
An intruder attempts to cut through the fence fabric.
•
An intruder attempts to climb over the fence.
•
An intruder attempts to crawl under the fence by lifting the fence fabric.
An intrusion alarm resets automatically when the event is over or when the Alarm
Hold Time lapses. The Alarm Hold Time is a factory setting which is used to
prevent subsequent alarms from being declared at the same location. The Alarm
Hold Time is three seconds, and cannot be adjusted. Once the processor
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FlexZone™ Product Guide