How Do Motion Sensor Flood Lights Work?

DIY Security Systems

Do you feel annoyed at times when you have to look for the light switch in the dark? What’s worse is when you have to go out of the house to throw the trash or go through a certain area where it’s pitch dark. Tripping around your house while trying to find a way to turn on the lights is not fun, especially when you’re up from sleep. How do motion sensor flood lights work? You may have to invest in motion-sensor floodlights as they will instantly turn on the moment they detect motion within range. Read on

What are Motion Sensor Lights?

Let’s begin with the fundamental aspects before we discuss how do motion sensor flood lights work. First, we have to identify what are motion sensor lights. As the name suggests, they are activated by a movement or motion. These lights have individual sensors that detect physical motion around their range. The sensors may release infrared energy, sound waves, or microwaves to determine if there are movements around.

Different Types of Motion Sensors

Before we proceed with how do motion sensor flood lights work, let us first familiarize ourselves with the different types of motion sensors.

Active Sensors

Active sensors are motion sensors that use radar waves, infrared energy, or related methods to recognize changes in rooms where they are located and monitoring. Three active sensors commonly used:

• Tomographic 
• Ultrasonic 
• Microwave

Tomographic sensors produce radio waves and are commonly used where a higher level of security is needed to give coverage for a wider area, such as solar-powered floodlights. 

Ultrasonic sensors are most often used in lighting, and they produce higher-level sound waves than human ears can hear. On the other hand, microwave sensors produce microwave pulses. The dilemma is that as they are usually able to pass through walls and other non-metallic stuff, they can set off false alarms if not calibrated properly. When active sensors are installed, they normally send out pulses of energy and measure how long it takes for the pulses to bounce back after they hit objects that are installed in a room. 

PIR or Passive Infrared Sensors

There’s only one type of passive sensor – the PIR or passive infrared sensor. How do motion sensor flood lights work using PIR? This motion detector functions by measuring the increases and decreases in infrared radiation or otherwise known as heat – the heat produced by humans, all warm-blooded animals, and the sun. Within the PIR sensors, there are two slots and a piece of thin pyroelectric material.   

 This is what responds to the IR radiation. When the two slots detect the same levels of heat, the sensor stays idle. This is what we call the calibrated ambient heat level of the room. But, if large animals or humans enter the covered area, it creates a positive differential charge between the two slots. This charge triggers the PIR sensor. They are calibrated to react to certain heat level changes, which means you need not worry about small and unimportant fluctuations turning the lights on like sunrise or small animals like cats and dogs. However, you need to be extra careful not to put any shelves or partition that will block the space you would want to be detected as the PIR sensors have only a line of sight and directional coverage. 

Dual Tech Motion Sensors or Dual Technology Sensors

With dual tech motion sensors, you will get the benefits of both the PIR sensor and the ultrasonic sensor in one efficient device. The lights only turn on when both the ultrasonic and PIR detect occupancy when you have dual tech motion sensors in place. Plus, as a bonus, one sensing tech can be kept active to keep the lights on when the room is occupied. This means that smaller movements like somebody typing or writing are detected by the ultrasonic sensor, but now a person walking down the hallway past the door.

Types of Lighting Motion Sensors

Occupancy vs. Vacancy

There are 2 types of lighting motion sensors – occupancy and vacancy varieties. Vacancy sensors turn the lights off in a room if it doesn’t detect any motion, and the room is empty, but there’s a need to switch on the lights manually every time you enter the room. While occupancy sensors turn on the lights automatically when it is tripped and switch it off again after a pre-determined amount of time without any movement. This kind of sensor works best in high-traffic rooms like bathrooms or restaurant pantries.