1.False alarm caused by improper design and installation of alarm system
Problems of equipment installation location, installation Angle, protective measures and system wiring, etc.
(1)When the passive infrared intrusion detectoris installed in front of the air conditioner or ventilator, it will cause false alarm of the system.
(2)Outdoor active infrared detector is not properly protected from sunshine, which causes false alarm of the system.
(3)When the distance between the alarm line and the power line, lighting line and other strong electric lines is less than 1.5m, and no anti-electromagnetic interference measures are taken, false alarm of the system will be caused.
2.False alarm caused by user improper use
For example, a window with a door magnetic switch is not plugged in and is blown open by the wind at night. Staff entered into the protected area. Someone accidentally triggered the emergency alarm device. Error operation made by system operator. Not paying attention to the change of working procedure. It can greatly reduce the false alarm frequency of the alarm system by analyzing the user’s improper use and making clear where the error is and improving the user’s level of using the alarm system.
3.False alarm caused by environmental interference
For example: hot air flow causes false alarm of passive infrared intrusion detector; The high frequency sound causes the false alarm of single technology glass breakage detector; The ultrasonic source causes the false alarm of the ultrasonic detector. A more effective measure to reduce such false alarms is the use of double-sensors detectors (when two sensors with different principles simultaneously detect the “target”, the alarm will send out an alarm signal).The products are: microwave – passive infrared double detector, acoustic – vibration glass broken double detector, ultrasonic – passive infrared double detector, etc. But some environmental interference detectors are useless. For example, rats are in the protection zone.Pets walking around in the house, etc.
Analysis and solution of false alarm problem
