A motion sensor light switch is nothing but a switch that responds when it senses movement of any sort. This is the technology that is used in simple light switches as well as advanced alarm systems where the switch trips and alerts the house owners of an intruder.

Any motion sensor light switch you come across in the market makes use of one of following three technologies:

1. Pyroelectric infrared sensors: These are known as PIR and work by identifying body heat. So, they activate when they sense heat from an individual.

2. Ultrasonic sensors: A motion sensor light switch that’s based on this technology will emit pulses and then analyze the reflections that bounce off the object.

3. Microwave sensors: These also perform in a similar manner to the Ultrasonic sensors in that they read the reflection that bounces off an object in motion. The only difference is the kind of pulse that’s emitted which is a microwave pulse.

Increasingly you’ll also find that a motion sensor light switch contains a combination of any two of the above mentioned technologies to improve its efficiency.

Having a motion sensor switch installed in your room, garage, kitchen or any other part of your house not only makes it easy to turn on the lights but is also a great way to save energy. Think of the benefits of having lights turn themselves off when you’re not in the room and they’re not required. With energy efficiency now on the top of ever planet friendly list, this could be your contribution to this worthy cause.

The best part is that you don’t have to spend big bucks to have this technology installed in your home. For a small price of about $25, you can buy yourself such a switch and install it yourself. These are commonly referred to as screw-in motion sensor switches. They are meant to be used with bulbs ranging from 25 – 100 watts.

All you have to do is unscrew your bulb in any part of the house, put the sensor in place and screw it in. Then, screw the light bulb back on top of it. That’s all it takes. Your motion sensor switch is now installed. Step outside from the room and the bulb will automatically turn itself off after a span of four minutes. These are meant for indoor use only and therefore are ideal for any enclosed space from your bedroom to the basement.

This motion sensor measures 4” in length and 3” in diameter. It’s capable of sensing motion in a clean 360° radius so you won’t need to worry about the light not turning on when you walk in, especially if your hands are full.

The only limitation of these screw-in motion sensor switches is that they can’t be used with compact fluorescent bulbs or CFLs. They are meant for bare light sockets that are made for bulbs which are mounted on the ceiling.

These handy motion sensing switches are manufactured by BRK.