Point Detector; Multi-Sensor Fire Detector - Siemens OH110 Technical Manual

3 Structure and function

Point detector

3.2 Point detector
3.2.1
16
Building Technologies
Fire Safety

Multi-sensor fire detector

The multi-sensor fire detector OH110 is a multiple-criteria fire detector with one
optical and one thermal sensor.
Structure and function
1 Labyrinth
2 Optical transmitter
The point detector has a high-quality opto-electronic measuring chamber. The
measuring chamber contains:
One optical transmitter
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One optical receiver
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One thermal sensor
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The transmitter lights up the smoke particles. The scattered light then hits the
receiver (photodiode) and generates a measurable electric signal.
In addition, the heat sensor makes it possible to detect fires in cases where no
smoke has been generated.
The combination of optical and thermal sensor signals optimizes detection
reliability with the following benefits.
Early detection of all types of fire, whether they generate light or dark smoke, or
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no smoke at all.
The fire detector can be operated at a lower sensitivity level, thus achieving
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improved immunity against false alarms which may be caused by cold
aerosols. In the event of an open fire, the smoke sensitivity level is raised by an
increase in temperature which makes rapidly burning fires easier to detect.
The multi-sensor fire detector OH110 has two parameter sets: 'Robust' and
'Sensitive'.
See also
2 Multi-sensor fire detector [➙ 29]
3
1
2
3 Optical receiver
4 Heat sensor
4
A6V10316298_e_en_--
2014-05-21