Product Description; Configuration Of The Detector; Functional Description Of Sensor Technology - Bosch MAGIC.SENS series Product Manual

Product Information MAGIC.SENS -- Product range

2. Product Description

2.1. Configuration of the Detector

1 = Smoke measuring chamber
(Optical sensor)
2 = Thermal sensor
3 = Chemical sensor
(covered on the
cross--section)
4 = Individual display
5 = PC board with evaluation
electronics
6 = Base MS 400

2.2. Functional Description of Sensor Technology

2.2.1. Optical sensor (smoke detector)
The optical sensor works according to the scattered light method.
A light diode sends light into the measuring chamber; this light is absorbed by the
labyrinth structure. In case of fire, smoke enters the measuring chamber. The light is
scattered by the smoke particles and hits the photo diodes that transform the quantity
of light into a proportional electrical signal.
2.2.2. Thermal Sensor (temperature detector)
A thermistor (2) arranged on a resistance network serves as a thermal sensor on which an
analog--digital converter measures the temperature--dependent voltage at cyclical intervals.
Depending on the detector class set, the temperature measurement unit switches to
an alarm state if the maximum temperature exceeds 54
(thermo--maximum) or a defined temperature increase within a particular time
(thermo--differential).
2.2.3. Chemical sensor (CO gas sensor)
The main function of the gas sensor (3) is to detect
carbon monoxide (CO) generated as a result of a fire,
but it will also detect hydrogen (H) and nitrous
monoxide (NO).
The underlying measurement principle is CO
oxidation and the measurable current that it creates.
The sensor signal value is proportional to the
concentration of gas.
The gas sensor delivers additional information to
effectively suppress deceptive values.
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2
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PI -- 34.65d
3
1
6
° C or 69 ° C
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BDL- -4998121218
A23.en /09.02.2007
ST- -FIR/ PRM1 / deh