What Do Infrared Detectors on Home Security Systems Do?

How They Work

• Infrared detectors read the infrared radiation in the area, monitoring for any sudden changes. Typically a security system has multiple infrared sensors in areas where an intruder would likely move through, such as a hallway or stairwell. An infrared sensor will only set off an alert when there is a change in the infrared radiation measured by the sensor, which change is consistent with a human moving through the area.

False Alarm Reduction

• Unlike other types of alarm system sensors, infrared sensors normally do not give false alarms. The sensors are programmed to not set off alarms if animals pass through the area since animals do give off a heat signature that is similar to humans but has a different shape and size. Motion detectors will sometimes give false alarms because a fan moves a curtain or the air conditioner in the house turns on, which infrared sensors will not do. If the cover on an infrared sensor becomes damaged, though, dust and other debris can enter and cause false alarms.

Fire and Other Protections

• Since infrared sensors pick up on a sudden change in heat patterns in the area, they can detect and send an alert in the event of a fire or an electrical device malfunctioning. Depending on the home security system, the system may even contact local fire authorities with the address of the property, potentially saving lives and reducing property damage because of the faster response time to the fire.

Economic and Durable

• Infrared detectors do not need a power source to operate like other sensors do, saving you on energy costs. Infrared detectors also cost less than other sensors, saving you money on the acquisition cost, and the sensors don't require as much upkeep, typically lasting years without problems. An infrared sensor can endure hard impacts, making them ideal for high-traffic areas where they may be knocked into occasionally.