PIR Detectors: Freeze! ...Literally

14 December 2015

In this day and age, there are many different technologies that work by reacting to a human’s presence or absence. We cannot walk down the street without something reacting to our movement – automatic doors, hand-dryers and burglar alarms to name just a few. We live in an automated world.

But not everything is focused on activity. A PIR detector doesn’t register movement – it detects heat instead.

How Do PIR Sensors Work?

PIR detectors work by detecting the heat of a human body, which is given off in the form of infrared radiation. Because of this, they are less temperamental and prone to false alarms than other types of sensors and some can even differentiate between small animals and humans!

Specially tuned to the wavelengths given out by this infrared heat, the detector is designed to monitor when there are temperature spikes in the room. The rise to body temperature signals the presence of a human as soon as they move within range of the detector.

What Are the Advantages of Using PIR Sensors?

Unlike motion detectors, there is no hiding or tricking a PIR sensor unless you do not have a temperature – in which case, you have bigger problems to worry about. It doesn’t matter if you race across a room hoping to be too fast or crawl slowly hoping to avoid detection. Keeping low or pretending to step over invisible beams makes no difference. Any change in temperature gives out these wavelengths and are picked up by the PIR detector.

That’s the “IR” part of the detector; the infrared waves. But what about the “p”? The “p” is because the detector is known as being passive. This doesn’t mean it sits there doing nothing and lets everyone sneak past it. Instead, it refers to how the detector does not give off any heat itself. Despite being made from electrical components, there is no heat radiating out of the detector, so it cannot trigger itself by heating up too much. It is a passive object in the room – it does not affect the readings. This again helps to limit the amount of false alarms and allows you to be sure that when the PIR does go off, something must be afoot.

PIR Sensors and Care Alarms

A PIR detector is not fool-proof – nothing is. But as every human being radiates a body temperature, it is an ideal way of keeping track of what is happening in the room. A ninja can sneak past a motion sensor: they can’t get past a PIR detector. This means there are a wide range of uses for a PIR detector, from an outside light to a care alarm.

Whether you use it as a motion sensor or a bed leaving monitor, a PIR detector is ideal for tracking the movements of your loved ones. Reacting to heat means nothing will happen if the pillow is thrown from the bed, but if a body crosses its detection field, it will be picked up on. If positioned correctly, they cannot escape the sensor, not even if they get out of bed from the other side.

No avoidance means no concern. Linked up with monitors and alarms, the PIR detector will inform you of what is going on so you do not need to worry. Not even about ninjas.

Visit Care Alarms to see our full range of PIR Sensors.

Silent Alert SA3000 Hard of Hearing Movement Monitor

A movement monitor for the Silent Alert system, the Silent Alert Movement Monitor alerts Silent Alert pagers when the infrared sensor detects movement.

Available, dispatched in 1-2 days  Available, dispatched in 1-2 days
(£147.16 ex vat)
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