PIR Sensors Explained

PIR sensors

How PIR sensors work

Burglar alarm systems have come a long way from primitive alarms that made annoying noises for hours on end. The key to each system - even with grating high pitched noises - was, and remains, PIR sensors. PIR Sensors (or Passive Infrared Sensors), measure the wavelengths of infrared light in your home, factory, or retail premises.

Infrared light radiation is emitted by passers by, whether animals or human beings. PIR sensors are typically fitted near points of entry or parts of the home close to valuable goods. Any changes in infrared radiation are triggered by sensors, which raise the alarm. Present day systems are designed to “ignore” cats and dogs.

The level of coverage from each sensor could vary from narrow angles to panoramic views with a 110° angle. Some PIRs have parabolic mirrors or a multitude of fresnel lenses. Each unit’s PCB has a relay which helps to trigger the alarm system.

PIR sensors can also incorporate CCTV cameras. As well as detecting movements, each movement can be recorded by the camera and sent to your mobile device.

We at Mertech Electrical are able to fit security systems for your home or industrial premises. Our systems are designed to fit around your needs, whether you’re the only occupant or run a factory with several employees. If you have any queries, call us on 07970 610237, or send us an email to info@mertechelectrical.co.uk. We’ll be delighted to be of service.

Mertech Electrical, 20 April 2017.


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