Why do fire detectors often set off false alarm

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vedard
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Joined: Wed Dec 05, 2018 12:27 am

Why do fire detectors often set off false alarm

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Why do fire detectors often set off false alarm?
1. Product quality is poor
The technical parameters of the product can not meet the requirements, the stability is poor, the sensitivity drift caused by non-fire factors in the working environment such as temperature, humidity, dust, wind speed can not be compensated or the compensation ability is low, and the influence of various interference and line analysis parameters can not be automatically processed and false alarm is set off.
2. Improper selection and placement of fire detectors
The selection of detectors is unreasonable: fire detectors with high sensitivity can alarm at very low smoke concentration, whereas detectors with low sensitivity can alarm only in high smoke concentration environment. For example, in the meeting room, underground garage and other places where smoke is easy to collect, high sensitivity smoke detector should be used. In the boiler room which is high temperature environment, constant temperature detector should be used.
The place utility is changed, but the fire detectors keep the same. For example, the office, shopping malls are change to kitchen, wash wash rooms, meeting rooms, the original smoke fire detector will make false alarm for cigarette smoke, water vapor, dust, pesticides and alcohols, ketones, ethers, etc corrosive gas and so on.
3. Environment factor
(1) Electromagnetic environmental interference: electromagnetic interference in the air, narrow pulse group of power supply and other input and output lines, human static electricity.
(2) Airflow can affect the flow line of smoke, which has a great influence on ion smoke detection, and also has a certain influence on photoelectric smoke detector.
(3) the heat detector is arranged too close to the high temperature light source, the smoke detector is too close to the air supply outlet of the air conditioner, and the temperature detector is installed in places that are easy to produce water vapor and garages.
(4) Photoelectric smoke detector is installed in places where black smoke, large amount of dust, steam and oil mist may be produced.
4. Other causes
(1) The system grounding is ignored or fails to meet the standard requirements, the line insulation fails to meet the requirements, the line joint is badly pressed or the wiring is unreasonable, and the dust-proof, moisture-proof and anti-corrosive measures are handled improperly before the system is opened.
(2) the aging of components, the service life of general fire detectors is about 10 years, and every 3 years requires comprehensive cleaning.
(3) dust and insects, according to relevant statistics, 60% of the false positives are due to the impact of dust.
(4) Detector damage.
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