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All You Need to Know About Motion Sensors

A motion sensor (or motion detector) is the key player of your security system because it’s the key device that detects when somebody is in your home when they shouldn’t be. A motion sensor uses one or numerous technologies to notice movement in an area. If a sensor is tripped, a warning sign is sent to your security system’s console, which connects to your monitoring device alerting you and the monitoring device to a possible threat in your residence.

The Role of Motion Sensors in Your Home Security

The main point of motion detection is to sense a burglar and send a warning sign to your control panel, which alerts your monitoring device. Sensors work when you are not home, or when you tell the system you are not home. Some security systems can be set to record events via a security camera when activity is detected.

Motion sensors stand guard, prepared to react to a variety of situations, such as movement in your living room, windows or doors being opened or closed, or a broken window.

Motion Sensors Can:

motion sensors on a wall
  • Alert you in the occurrence that your son/daughter breaks curfew
  • Set off a doorbell when somebody approaches the front door
  • Alert you when kids enter classified areas in the home, like the cellar, workout room, or medication cabinets
  • Save energy by using motion sensor lighting in empty spaces
  • Inform you if pets go into areas where they’re not supposed to

Types of Motion Sensors

Passive Infrared (PIR)

Detects body heat (infrared energy). Passive infrared sensors are the most extensively used motion in home security systems. When your system is prepared, your motion sensors are activated. Once the sensor warms up, it can sense heat and movement in the immediate areas, creating a defensive “grid.” If a moving object blocks a lot of grid zones and the infrared energy levels change rapidly, the sensors are triggered.

Microwave (MW)

Sends out microwave pulses and measures the signal off a moving object. They cover a big area compared infrared sensors, but they are susceptible to electrical intrusion and are more costly.

motion sensors on a wall

Dual Technology Motion Sensors

Motion sensors can have shared features in an effort to decrease false alarms. For example, a passive infrared (PIR) sensor could be shared with a microwave sensor. Since each operates in multiple areas of the scale, and one is inactive and one is active, Dual Technology motion sensors are not as likely as other types to reason false alarms, In order for the alarms to react. The sensors have to be triggered. On the other hand, this does not mean that they, for no reason cause false alarms.

Area Reflective Type

Emits infrared rays from an LED. Using the signal of those rays, the sensor measures the distance to the individual or object and detects if the object is within the selected area.


Measures the reflection of a moving object and sends out pulses of ultrasonic waves.


These can be purchased or with no trouble made at home. Detects shaking. A homemade vibration sensor uses little mass on a lever, which is activated by a knob to an alarm when it vibrates. Homemade motion sensors are able to work, but they can also be unpredictable.

Other Motion Sensor Characteristics

Wireless Motion Sensors

Nowadays, most motion sensors are wireless. Wireless sensors are very simple to set up. They do not need drilling, and they commune with the other security system mechanism wirelessly.

Contact Motion Sensors (door/window)

A lot of contact motion sensors are reactive infrared sensors. They set off an alarm if the protected door or window is opened while the system is equipped.

Pet Immune Motion Sensors

A passive infrared sensor can be set up to pay no attention to animals up to a definite weight. A double technology motion sensor is more defiant to false alarms caused by animals since it needs two sensors to be triggered in a way determined by the company.

They can be set up to disregard a large animal or numerous small animals without setting off a false alarm. Some pet resistant motion sensors have a sensitivity level that can be attuned for families with very active animals.

Video Motion Sensors

Links video cameras with advanced signal processing. Some recordable motion sensors set off recording when they sense motion. Cameras controlled by motion sensors can save you memory storage by not recording thousands of hours of useless footage—they only capture the significant information.

Best Practices for Mounting Sensors

If you want a system that needs specialized installation, the installer will know to set up your sensors. on the other hand, you are accountable for setting up your sensors if you go with a DIY home security system. Prior to installing motion sensors, make sure to read the setup instructions, since they will likely consist of position recommendations. Some DIY systems also provide you with electronic prompts or have you call a sales rep that will walk you through the setup procedure.

Keep in mind that motion sensors are not error-proof, and there are instances in which there might be false alarms. False alarms are more often than not caused by electrical failures, user error, poor application engineering, power surges, lightning, and faulty apparatus. They can also be triggered by animals, insects, and plants.