PIR VS Microwave, How to Choose a Right Sensor

There are many motion-sensitive solutions in the market, it helps saving energy bills when with dim to off when no absence, and also keep safe for house when anyone reaching. Motion-sensitive solutions bring convenience and help a lot in our life. Most sensors in the market work in 2 ways: PIR defection and Microwave detection. Do you really know how to choose a right sensor?

What are PIR sensors?

PIR sensors, are “passive infrared” sensors, receiving the heat source passively. They usually come with special lens, which have many slots.

When heat source come in the sensor detective range, one slot receives over heat than that other slot does, the PIR sensor is triggered and turn on luminaire.

When heat source leave, all slots receive same heat, the PIR sensor will resume and turn off luminaire.

What are Microwave sensors?

Microwave sensors, emit microwave signals actively and constantly.

When there are absence in sensor detective range, microwave signals are reflected back to sensor, which is triggered and turn on the luminaire.

When the absence disappear in the sensor detective range, the sensor return to normal and turn off luminaire.

As you can see, both PIR sensors and Microwave sensors are motion-sensitive sensors, there is no direct advantage or disadvantage for both sensors, their working ways make them are applicable for different occasions.

How to choose a right sensor?

PIR sensors are sensitive with heat, they need to detect the temperature difference between heat source and environment, so PIR sensors are not suitable for areas or places where are hot, such as oven area in food processing factory, metal processing area. While, microwave motion sensor will not be affected by temperature.

PIR sensors are triggered by heat, so the suitable location is where the target can be detected, such as corridors, entries, walkway, etc. However, microwave sensors no need the sight of movement, therefore it will be good for large room, such as factory, warehouse with a lot of obstacles.

Important things for microwave sensors,

• Over sensitive: be careful with metal devices, such as large machines, metal roofs, shelves, etc. Sometimes, microwave signals would be reflected by these metal surface, so sensors become over sensitive, which make luminaires glimming.
• Under sensitive: some microwave signals could not go through glass and wall, so these obstacles will make sensor under sensitive.
• Others: microwave sensors may be affected by blowing leaves or waving branches, these should be considered when using them in outdoor.

Consult with AGC firstly before you choose a sensor, we will give some professional suggestions to avoid your future trouble after mounting.