One-zone detection vs. two-zone detection – Inovonics FA206S User Manual

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02311D.DOC LIT-FA206S-INSTALL hc:31-Aug-01

One-zone detection vs. Two-zone detection:

Placement of the Zone detection jumper determines how much motion it will take to trigger the
Sharpshooter. By way of explanation, think of the Sharpshooter as looking out at the protected area in a
series of wedge-shaped zones beginning inside the unit at 2 small pyroelectric sensors. Two of these
wedges comprise a zone. Infrared energy travels up the wedges and is focused by the Fresnel lens onto
the pyroelectric sensors. One sensor creates a positive voltage spike when subjected to a temperature
change, the other a negative spike. A target moving across the adjacent positive and negative wedges of
a zone creates a characteristic electrical "signature". Sophisticated software analyzes the waveforms
created by the sensors before triggering an alarm.

The one-zone detection option tells the Sharpshooter that changes in any adjacent wedges should cause
an alarm. This setting is required for long-range lenses and curtain lenses. In standard lenses, however,
one-zone detection makes the unit very sensitive to minor temperature variations in the environment, and
can result in false alarms.

Two-zone detection requires intruders to move across at least four wedges. At typical operating distances
from the Sharpshooter, the target has to move several feet before an alarm will be generated. False
alarms due to localized heat fluctuations are nearly eliminated.

1-zone detection

2-zone detection

1-zone or 2-zone

detection header

FA206

1-Zone Detection

2-Zone Detection

ALARM