A security system involves several components that integrate to provide robust security. Among them is a motion sensor that detects anomalies on your site when you are not physically present to alert you. This blog talks about motion sensor alarms and how it works and what it can do for your business.

What is a Motion Sensor Alarm?

A motion sensor alarm is a device used to detect intruders in a facility and trigger an alarm based on that. It detects movement in a specific area using optical, infrared or microwave sensors. Motion sensor alarms are commonly used for security, automation, and convenience purposes.

Motion sensor alarms or simply motion sensors can be used for the following:


Motion sensor alarms can be used to protect the property, the valuables, and the people from intruders, burglars, or trespassers. They can alert the user or the authorities of any unauthorized entry or activity in the area. They can also deter or scare away the potential threats with loud noises or flashing lights.


Motion sensor alarms can also be used to control or activate other devices or systems based on the detected motion. They can turn on or off the lights, the heating, the cooling, the ventilation, or the appliances when someone enters or leaves the room. They can also adjust the settings or the intensity of these devices according to the level of activity in the area.


Motion sensor alarms can be used to make life easier and more comfortable for the user. They can open or close the doors and windows or be set to play a specific message in case someone is detected on site. This can ward off trespassers, or give specific information to people on the premises.

What are the Components of Motion Sensor Alarms?

A motion sensor alarm typically consists of the following main components:

  • A microwave, infrared, or ultrasonic wave emitter that puts out waves throughout the room, which is used to detect motion.

  • A sensor or receiver that detects motion using various technologies such as infrared, ultrasonic, microwave, or camera.
  • A control unit that processes the signal from the sensor and determines whether to activate the alarm or not.

  • An alarm that produces a sound, a light, a message, or a combination of these to notify the user or the authorities of the detected motion.
  • The Mobile App is used to interact with and see information about the alarm system.

The motion sensor alarm can also be connected to a motion sensor camera that can be set to go off if motion is detected to capture the intruder. This acts as a visual confirmation for the responder.

How Do Motion Sensor Alarms Work?

There are different types of motion sensor alarms based on the technology they use to detect motion.

Some of the most common ones are:

Passive infrared (PIR) motion sensor

(PIR) motion sensor alarms use infrared radiation to detect the heat emitted by humans and animals. They are sensitive to changes in temperature and can work in the dark. However, they may not detect motion through walls, glass, or other obstacles.

Active infrared (AIR) motion sensor

(AIR) motion sensor alarms use infrared beams to create a grid or a perimeter around the area to be monitored. They detect motion when the beam is interrupted by an object. They are immune to environmental factors such as heat, dust, or smoke. However, they may be triggered by small animals, insects, or leaves.

Ultrasonic motion sensor

Ultrasonic motion sensor alarms use high-frequency sound waves to measure the distance and the speed of the objects in the area. They detect motion when the sound waves bounce back differently from the moving objects. They can cover a large area and can work through walls and other materials. However, they may be affected by noise, wind, or humidity.

Microwave motion sensor

Microwave motion sensor alarms use electromagnetic waves to scan the area and detect the movement of the objects. They detect motion when the waves reflect back differently from the moving objects. They can penetrate walls and other materials and can cover a large area. However, they may be interfered with by other devices that use the same frequency, such as radios, phones, or microwaves.

Camera motion sensor

Camera motion sensor alarms use image processing to analyze the video feed from a camera and detect the changes in the pixels. They detect motion when the pixels change significantly from one frame to another. They can provide visual evidence of the motion and can be integrated with other features such as face recognition, night vision, or zoom. However, they may require more power and storage than other types of motion sensor alarms.

How To Install Motion Sensor Alarms?

Motion sensor alarms can be installed either as wired or wireless systems. Depending on the usage and the budget, picking the right one for your business requires careful consideration of the pros and cons of both.

Wired Systems

Wired systems require a physical connection between the sensor, the control unit, and the alarm. They are more reliable and secure, but they may be more difficult and costly to install and maintain. These systems are more suited for businesses, since homeowners are less likely to want excessive wiring in their homes.

The greatest benefit of wired motion sensors is that there is a lower risk of malfunctioning, due to lesser chance of interference and the lack of batteries. Moreover, they require little to no maintenance as well.

Wireless Systems

Wireless systems use radio signals or Wi-Fi to communicate between the sensor, the control unit, and the alarm. They are more flexible and convenient but may be more prone to interference, hacking, or battery issues. wireless sensors are better for homes because they are more pleasing to the eye and do not require installation. Maintenance requires changing batteries and keeping up with the firmware updates to keep the system running.

Where are Motion Sensor Alarms Used?

Motion sensor alarms can be used in various places and businesses/industries where motion detection is needed or desired. They are primarily used to improve security where they can detect intruders, burglars or trespassers.

Some of places where motion sensor alarms can be used are the following:

Homes And Multifamily Residential Buildings

Motion sensor alarms can be used in homes to enhance the security, ease up automation and improve the convenience of the residents. They can be installed in the entrances, the hallways, the bedrooms, the bathrooms, the kitchens, the garages, or the gardens.

Office Buildings and Complexes

Motion sensor alarms can be used in offices to improve security, productivity, and the sense of safety of employees. They can be installed in the reception, the conference rooms, the cubicles, the restrooms, the cafeterias, or the parking lots. They free up time and other resources of the business which can be spent elsewhere to create more value for the business.

Retail Shops And Stores

Motion sensor alarms can be used in shops to improve control measures, increase customer satisfaction, and the safety of the products. They can be installed in the display windows, the aisles, the fitting rooms, and the doors for when the store is closed.

Schools And College Campuses

Motion sensor alarms can be installed in the classrooms, the libraries, the laboratories, the auditoriums, or the playgrounds. They improve security by alerting responders of activity where there should not be, leading to swift action by law enforcement.


Motion sensor alarms can be used in hospitals to improve the health, the care, and the safety of the patients and the staff. They can be installed in the wards, the operating rooms, the intensive care units, the pharmacies, or the emergency exits.

Construction Sites

They can also be used on construction sites to prevent theft of equipment from the site. Valuable material and equipment remains overnight on construction sites, and motion sensors can alert the security team of activity during non-working hours.

Parking Lots

Motion sensor alarms can help improve security and efficiency in parking garages. They can help deter car theft, detect intruders, and control access. They can also help save energy by turning on the lights only when motion is detected.

How To Pick The Right Motion Sensor Alarm For Your Business?

Choosing a good motion sensor alarm depends on your needs and preferences. Here are some factors to consider:

  • Cost: Motion sensor alarms vary in price depending on the type, the features, and the quality. You should compare different options and find one that fits your budget and offers the best value for money.
  • Range of detection: Motion sensor alarms have different ranges of detection, which means how far they can sense motion. You should choose one that covers the area you want to monitor and does not miss any blind spots or false alarms.
  • Ease of use and installation: Motion sensor alarms have different levels of complexity and difficulty in terms of installation and operation. You should choose one that is easy to set up and use, and does not require too much maintenance or troubleshooting.
  • Effectiveness: Motion sensor alarms have different ways of notifying you and/or your professional monitors that something has been detected. You should choose one that has a reliable and clear alert system, such as a sound, a light, a message, or a combination of these. You should also choose one that has a low rate of false alarms and a high rate of accuracy.

Looking For Motion Sensor Alarm Systems in Canada?

Are you looking for a motion sensor alarm system for your business in Canada? Installing security systems yourself is an option, however, employing a security company makes sure that your system faces no hiccups.

Spotter Security installs, maintains and manages motion sensor alarm systems for your business so you never have to worry about security. With over 20 years of experience and expertise in the security industry, Spotter Security knows your business and can help you secure it.

Written by : Carlo Di Leo

At the age of 24, with no experience in the security industry or any money in the bank, Carlo quit his job and started Spotter Security from his parent's basement. Founded in 2004, Spotter grew from a single man operation into a multi-million dollar security system integrator that caters to businessess and construction sites across Canada.

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