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  • July 22, 2019

    What Waves Are Used in Intruder Alarms

    Intruder alarm systems Investing in a security system is important for making sure that the property is safe from external threats.  A property whether it is domestic or commercial needs to be protected against burglars and intruders. There are so many different types of alarms available in the market and the choices can get pretty overwhelming. Deciding the type of sensor to install is an important decision. To understand the working of the different intruder alarm systems you have to know a little about the type of sensors that are used in the alarms. Here is a guide that will help you in understanding the types of sensors that are used in the intruder alarms. Ultrasonic detectors The ultrasonic detectors have high-frequency sound waves to detect movement. The sensor has the ability to detect movement within a limited space. They have the ability to transmit frequencies that are between 25 kHz and 75 kHz. The frequency range is inaudible to the human ears. The ultrasonic detectors bounce these frequencies off the ceiling, walls, and furniture and if there is any sudden change detected the alarm will be triggered. The frequency bouncing off the walls, furniture or ceiling can be changed by any moving object. This type of intruder alarms is often used in high-security places where the access is limited because the alarm does not discriminate between an intruder and passersby. Passive infrared motion detectors These detectors are also known as the PIR sensors and they are a common choice among the homeowners. They are preferred by homeowners because they are affordable and practical. The term passive is used for these alarms because they operate without any need for generating or radiating energy. The PIR sensors have the ability to efficiently detect the changes in ambient temperature and body heat....