How Motion Sensor Lights Work

House Night 179061993Motion sensor lights are fairly simple in theory – when the sensor detects motion, it triggers the light to turn on. But more than that, motion detector lighting has a lot of interesting ways in which it works, each providing unique benefits to the owner of the home who has chosen them for their security lighting. With the different types of sensors available for motion sensor lights, you’ll see that they have clear advantages in various settings; thus, you’ll be able to determine which ones might be right for your home.

Types of Sensors

  • Radar – Just like military planes can detect nearby aircraft using radar, some sensors use radar to detect that someone has walked by. These are common in the automatic doors that open grocery stores and are less common for homes.
  • PIR Detectors – Passive Infrared sensors, called PIRs, are what most motion sensor lights are in residential homes. They passively detect infrared energy transmitted by humans. Because we humans radiate infrared energy due to our warm temperatures, PIR detectors are sensitized to sense or detect the infrared energy wavelengths at the temperature of the human body. But rather than sensing only the transmission of those wavelengths of energy, PIRs are made with attachments to sense when there has been a quick change in the wavelengths it senses. Basically, when a person walks or moves nearby, the wavelengths are altered and the sensor recognizes it. Thus, motion sensor lights won’t react to slow changes in infrared light such as the sun slowly setting. These lights are more effective for perimeter security when placed outside, because the energy wavelengths from the infrared light sent off by the human body will not transmit well through the glass of a window. So if a person is looking through your window, an interior motion sensor light will not be able to detect their movements. For this reason, the security lights should also not be put behind bushes or furniture – they need a clear line of sight to be able to detect motion. Additionally, they need to be kept at an appropriate distance from heat sources such as clothing dryers so as to not interfere with their detection.
  • Smart Sensors – Some sensors are able to detect the natural light in the room and know when not to switch on the light because it is not needed. This is a convenient way of saving even more in energy costs through the use of motion sensor lighting.
  • A vacancy sensor, also known as a manual-on sensor, when manually set ON, will then turn off when the room has been vacated. These are common in classrooms and businesses but can also be used in homes.
  • An occupancy sensor, also called a motion sensor, will turn the light on when the sensor detects motion, then remain on until no more motion is detected. Of course, this is what usually comes to mind first when thinking of motion sensor lights. Occupancy motion sensor lights are particularly useful for security but also for home automation in rooms such as basements, garages, laundry rooms, closets, etc. where you don’t typically spend a lot of time, so that turning the lights on and off for 1 minute is no longer a hassle you have to deal with.

What The Sensor Reacts To – Vacancy vs. Occupancy Sensors

motion-alarms-135448943Both of these types of motion sensor lights are rapidly becoming commonplace because of their convenience, security, and lower energy and electric bills. And in addition, they are affordable and easy to install; they can even simply replace any standard wall light switch you have already in your home. Sensors can work with a variety of bulb types, including incandescent, LED, halogen, fluorescent, and more; just make sure that one you choose will work with the bulb you’d like to pair it with.

Types of Motion Sensor Mounts

  • Ceiling-Mount – This type provides overall coverage for the room and allows motion to be freely detected, not obstructed by furniture. These are ideal for big, open rooms such as garages, dining rooms, and family rooms, as well as hallways, which are narrow and don’t have much room for wall or fixture mounts.
  • Wall-Mount – Areas that are irregularly shaped, such as stairwells or hallways, can benefit from a wall-mount, which can be adjustable to be fixed at the appropriate angle.
  • Fixture-Mount – To be mounted onto fixtures, these are best for task lighting or offices.
  • Wall Switch – This is the most common motion sensor light mount; it simply replaces a wall switch that is already installed. They are best in children’s rooms, main living areas, bathrooms, pantries, and also basements and garages.

Knowing how differently these sensors function from each other, it is easy to see the benefits of some over the others in specific settings. Use this information in deciding what you want for your home automation system.