Passive infrared sensor

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A passive infrared sensor (PIR) is a type of motion detector commonly used in burglar alarm systems for both commercial and residential properties. PIR sensors detect changes in infrared radiation, which is emitted by all objects with a temperature above absolute zero. When an intruder enters a room, their body heat will cause a change in the infrared radiation detected by the PIR sensor, triggering the alarm system.

PIR sensors are popular in burglar alarm systems because they are reliable, cost-effective, and easy to install. They are also less prone to false alarms than other types of motion detectors, such as ultrasonic sensors or microwave sensors. PIR sensors can be used in a variety of settings, including homes, offices, warehouses, and retail stores.

CGSmith is a business and residential security system installation and monitoring company based out of the Milwaukee WI area. As a leading provider of security solutions, CGSmith offers a range of services to help protect homes and businesses from intruders. This includes the installation of PIR sensors as part of a comprehensive burglar alarm system.

At CGSmith, we understand the importance of keeping your property safe and secure. That’s why we offer customized security solutions tailored to meet the unique needs of each of our clients. Whether you need a basic burglar alarm system or a more advanced security system with video surveillance and remote monitoring capabilities, we can help.

If you’re interested in learning more about PIR sensors and how they can be used to enhance the security of your property, we encourage you to visit our Contact Us page. Our team of security experts is available to answer any questions you may have and provide you with a free consultation to help you determine the best security solution for your needs. Contact us today to learn more!


1. What is a passive infrared sensor in a burglar alarm?

A passive infrared sensor (PIR) is a type of motion detector used in burglar alarms. It detects changes in infrared radiation emitted by objects in its field of view, such as a person moving through a room. When the sensor detects motion, it sends a signal to the alarm control panel, which triggers an alarm.

2. How does a passive infrared sensor work in a burglar alarm?

A passive infrared sensor works by detecting changes in the infrared radiation emitted by objects in its field of view. When a person or animal moves through the sensor’s detection area, it detects the change in infrared radiation and sends a signal to the alarm control panel. The control panel then triggers an alarm, alerting the homeowner or security monitoring service.

3. Where should I install a passive infrared sensor in my home for maximum effectiveness?

To maximize the effectiveness of a passive infrared sensor, it should be installed in a location where it has a clear view of the area you want to protect. Typically, PIR sensors are installed in the corners of rooms or hallways, where they can detect motion across a wide area. It’s important to avoid placing the sensor near sources of heat or cold, such as windows or air conditioning vents, as this can cause false alarms.

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