GIRA
Info
Observer 180 plus
Installation Instructions
Observer 180 plus
28/99
Page: 11 of 13
2,
4
m
16m
A Few Remarks on the Working Range
The Optical System and its Alignment
With its many optical lenses, the observer "looks" slantwise down
from its place of installation.
z
At the specified installation height of 2.4 m,
z
with the sensor head not tilted,
z
and in plain terrain, the most remote beams hit the ground at a
distance
of
16 m
.
This value is specified as the rated working range of the unit.
The working range
reduces
:
z
in rising terrain,
z
with the sensor head tilted down,
z
and at an installation height of less than 2.4 m.
The working range
increases
:
z
in falling terrain,
z
with the sensor head tilted up,
z
and at an installation height of more than 2.4 m.
34 °C
33 °C
24 °C
26 °C
ca.
Moving Heat Sources
The observer (PIR) responds to thermal changes within the
detection field. The higher the relative temperature difference
between the moving heat source and the environment is, the more
sensitively the observer acts.
Temperature profile of the human body (example). The thermal
energy radiated by the body depends upon the clothing.
When a person enters the detection field, he/she is, first of all,
detected by his/her feet.
Good detection or no response yet is obtained, depending upon
the temperature of his/her shoes and the ground. If the tempe-
rature difference is not sufficient for detection when a person
enters the detection field, the person must go closer to the
observer to be detected, i. e. the working range decreases:
