Whether for indoor or outdoor use, a motion sensor light is always one of the optimal lighting solutions combining energy-saving, illumination, convenience, automation, and security at the same time. A motion sensor light will automatically turn on when you enter your room or when the motion sensor detects someone suspicious outside your house.
It’s not easy, sometimes even complicated, to select an ideal motion sensor light for your house because there are many factors to consider, such as the power supply, installation method, and light styles. We write this guide to help you learn about indoor and outdoor motion sensor lights, so you know how to use and pick the best motion sensor lights that suit your actual demand.
What Is a Motion Sensor Light
A motion sensor light is motion-activated by a motion sensor inside the light that will automatically turn on when the sensor detects people or motion nearby and automatically turn off when it no longer detects the motion to reduce electricity waste.
Motion sensor lights are mainly used outdoors as outdoor security lights for their ability to detect suspicious human activities near your property to deter crime. Most of the time, the motion sensor lights are completely automatic and do not require manual operation, which is ideal for placing and using outdoors.
Indoor motion sensor lights are popular as well, such as cabinet lights, closet lights, or night lights for the primary purpose of illumination, energy-saving, and convenience. For the main indoor ceiling lights in the house, we would normally use motion sensor light switches to control the regular lights rather than using a motion sensor light directly.
It’s very inconvenient to wait for the motion sensor light to turn off by itself after the timer expires when we need to immediately turn the light off. With motion sensor wall switches, it’s so much easier for people to have direct manual control to override and bypass the motion sensor. In the meantime, indoor motion sensor lights are more frequently used in hallways or stairways where people simply pass by occasionally, so we don’t have to wait for the light to turn off.
How Do Motion Sensor Lights Work
A motion sensor light turns on when it detects motion and turns off when it no longer detects the motion. Because the motion sensor directly controls the power to the light bulb, only when the motion sensor detects motion will it send electricity to the light to turn the light on. When the motion sensor no longer detects motion, it interrupts the electricity to the light then the light is turned off.
There are many types of motion sensors, such as PIR motion sensors, ultrasonic motion sensors, and microwave motion sensors. Almost every motion sensor light utilizes the passive infrared motion sensor as the motion detector because PIR motion sensors are extraordinarily durable, cheap, consistent, and consume very little power. The PIR motion sensor is excellent at reducing electricity consumption to expand the working hours for the battery-operated or solar-powered motion sensor lights.
The PIR motion sensor can detect motion within the detection range from 20 feet to 70 feet, sometimes up to 100 feet(30 meters). When the PIR motion sensor detects people, the light is turned on and will last about 20 seconds to 10 minutes depending on the timer setting and then automatically turn off.
Most motion sensor lights are highly adjustable, allowing users to customize several functions and settings on the light to make it more suitable for various situations.
The common settings on motion sensor lights include:
Motion sensor lights with ambient light detection will only turn on when the ambient light is insufficient to further avoid electricity waste in the daytime. The motion sensor light contains a light sensor inside to detect the ambient lighting and compare to its LUX value, which roughly represents the environmental brightness. The ambient light feature is also known as light-sensing or daylight sensing on other models.
When the ambient lighting is higher than the pre-set LUX value, it means the environment is bright enough, so the light will not get triggered by the motion sensor. When the environmental light is below the light sensor’s selected LUX value, the motion sensor is now able to turn on the light to provide sufficient illumination.
Typically, users can select the ambient light from various pre-set values from off to 50 LUX to suit their demands. When the ambient light setting is selected off, the light will turn on whenever the motion sensor detects motion even in the daytime, which may cause unnecessary lighting waste.
Dusk to Dawn
Dusk to dawn is a term similar to ambient light, which is exclusively used on outdoor lights. As the name suggests, dusk to dawn lights turn and keep on after the sunset in the evening and turn off after sunrise in the morning.
Dusk to dawn motion sensor lights are often more flexible than regular dusk to dawn lights with additional options. The dusk to dawn motion sensor lights can work the same as regular dusk to dawn light which keeps ON in the night and keeps OFF in the daytime.
It’s also available to keep the light off the entire day and only turns on when it detects motion at night. Some advanced dusk to dawn light allows the light to keep dimming at night and turn on full brightness when motion detected so your yard could have sufficient illumination the entire night for proper navigation but not completely dark.
The timer setting is the time for how long the light is additionally kept ON before being turned off as long as the motion sensor is detecting motion. The motion sensor light’s timer is the same thing as the time delay of the motion sensor. For different models, users can select a time period from as little as 5 seconds to as long as 30 minutes.
For example, a “30 seconds” timer means the light is still on for another 30 seconds when the motion sensor no longer detects motion.
The shorter timer you set on the light, the more energy it can save, but it is also bad for the user experience because the light might suddenly turn off while you are still in the place. In contrast, a longer timer may cause unnecessary electricity waste. Find an appropriate time setting, usually between 30 seconds to 5 minutes, for the best balance between energy saving and enough illumination.
The sensor sensitivity, also known as detention range in some motion sensor light models, allows users to customize how far/sensitive the motion sensor can detect with usually three levels from low, medium to high to target the most accurate detection coverage.
When the light is not turning on when you walk towards the motion sensor, it’s possible that the sensitivity is too low. Try setting the sensitivity to high to solve the problem.
When the light often accidentally or falsely turns on, it’s possible that the motion sensor is too sensitive that it has been detecting other motion activities such as moving cars and animals. You can set the sensor sensitivity to low to avoid the sensor from detecting too far away.
The default motion detection mode for most motion sensor lights is auto ON and auto OFF for the purpose of automation and convenience. Some motion sensor lights, especially indoor lights, might provide a manual mode that allows users to have more direct control of the lights. With the manual override feature, users can turn ON and OFF the light immediately, which would be extremely helpful for homeowners.
For outdoor motion sensors lights that do not have a built-in override feature, you can add a light switch directly to the light to bypass the control of the motion sensor. Some outdoor motion sensor lights provide a manual mode that allows users to control the light independently via a switch. If you frequently need to keep your outdoor lights on, you should consider buying one of these lights with such a feature.
Why Use Motion Sensor Lights
Motion sensor lights add automated lighting, convenience, and security to your house while reducing energy waste and lowering your electricity bills at the same time. A motion sensor light has everything that an ordinary light has, and there is simply no reason not to use a motion sensor light with the added useful features.
The major benefits of using a motion sensor light include:
Convenience and Automation
A motion sensor light is clearly more convenient to use than a regular light, and they require no touch, making them child and disabled friendly. It can be completely hands-free and automated without you operating a thing.
You don’t have to reach to the light switch when it’s not so convenient such as in the dark room or with a full arm. What’s more, you’ll never have to go back to turn the lights off after you already leave the area, such as leaving your home storage room or leaving your house in the dark with the lights on.
Though motion sensor light switches control the majority of indoor ceiling lights, there is battery-powered stick-anywhere type motion sensor light that is extremely popular and widely used to provide illumination in your home such as stairs, bedrooms, under kitchen cupboard, or in the closet where hardwired lights are not a good option. For example, when you are cooking in the kitchen, selecting clothes in your wardrobe, walking the stairs at night, the light will be auto on for you and turned off after you leave.
Most motion sensor lights are used outdoors to provide illumination to your yard, driveway and garage around your property. Almost all outdoor motion sensor lights are fully motion-activated. When you come back home in the dark, the motion sensor light will turn on for you to illuminate the path for easy navigation and automatically turns off after you enter the house.
Save Energy and Cut Electricity Bills
Needless to say, motion sensor lights can reduce electricity waste and cut our electricity bills. But by how much?
On average, motion sensor lights can save energy from 30% to 60% depending on your use case and applications, sometimes up to 80% in places with heavy lighting use time, compared to normal halogen lights.
Additionally, it’s a total waste of electricity to keep the light ON when there are no people in the place, and it’s also causing light pollution at night that disrupts the natural patterns of wildlife and human sleep and contributes to the increase in carbon dioxide.
Add Safety and Security to Your Home
When we are talking about security lights, we are talking about the outdoor motion sensor lights. The outdoor motion sensor lights, usually floodlights or spotlights, can help deter crime and burglars.
Burglars are highly likely to startle and give up the crime when the motion sensor spots and detects their presence, unexpectedly turns on the light and illuminates the space outside your property. The intruders find it hard to hide their existence without the dark cloaks removed by the ample lighting from the security light.
When the light is on, the burglars know that they have been spotted and detected. Even worse, the security light might connect with a security camera that already records their faces and trigger the alarms. It’s a high chance that they will give up the crime and escape the areas fast.
Indoor motion sensor lights can contribute to adding safety to your home as well. These night lights and stair lights can provide adequate illumination at night to prevent children and the elderly from getting injured from accidental falling or tripping.
Motion Sensor Light Types
As long as a light connects to a motion sensor and becomes motion-activated, it is now a motion sensor light. So there are various types of motion lights available on the market, such as security floodlights, spotlights, night lights or even motion sensor light bulbs.
Motion Sensor Floodlight
Floodlights are broad-beamed, high-intensity artificial lights that can spread the lighting to illuminate a wide range of outdoor fields, and they usually consist of 2 or 3 adjustable heads to provide ample lighting and illumination coverage. Motion sensor floodlights are commonly used as outdoor security lights for their bright and broad illumination and detection coverage up to 72 feet away at an angle of 150 – 180 degrees.
Motion sensor flood lights are mainly used outdoors, so they are made of weather-resistant materials to withstand water, rust, erosion, UV exposure and other weather elements for long-time durability.
Motion Sensor Spotlight
Motion sensor spotlights project a bright beam of light to spot a specific area such as front doors, doorways, steps and corridors. Spotlights are compact in size, allowing them to be used in cramped areas as well.
Compared to floodlights that spread the light into a broad area, spotlights are often used in groups to illuminate different areas in your house where lighting is needed. In this case, motion sensor spotlights are usually wireless, battery-operated or solar-powered, so they can be easily placed and installed anywhere without the need for wirings.
Motion Sensor Porch Light
Besides the illumination that a regular motion sensor light provides, porch lights can add extra decor and a cozy atmosphere to your house. Porch lights illuminate warm lights, sufficient enough for seeing the pathway but not too bright to hurt your eyes at night.
Motion sensor porch light can be highly practical and can detect people very well with the motion sensor built on the top of the lantern after properly mounted on the wall outside your house.
Motion Sensor Light Bulb
Motion sensor light bulbs are a very convenient motion-activated lighting solution without the need for any modification or installation process. It’s a standard light bulb with a PIR motion sensor embedded at the tip of the bulb that can be installed directly into a standard light socket and start working automatically.
The downside of using a motion sensor light bulb is that the detecting range is limited. You need to point the motion sensor to the desired detection area or the light will only react to people walking downside the light blub. Don’t install the light bulb in a total enclosed fixture which would block the sensor from correctly detecting motion.
Motion Sensor Light Socket
The motion sensor light socket is similar to a light bulb, requiring only a regular light bulb to work. Motion sensor light socket is also a preferable alternative motion-activated solution that can work out of the box without extra handwork.
The motion sensor light socket can usually provide extra adjustment settings than a light bulb such as timer and daylight sensing because it has a bigger capacity to contain these small components.
Indoor Motion Sensor Light
Indoor motion sensor lights are a group of lights for interior use inside your house. Indoor motion lights often include motion sensor puck lights, LED light bars, strip lights, ceiling lights or night lights.
The primary indoor motion sensor lighting is achieved with the help of motion sensor light switches which can offer more manual controls for users. Indoor motion sensor lights are a great complementary to provide lighting in corners, compact areas and inner compartments where the major ceiling light cannot thoroughly cover, such as closets, stairs, cabinets.
Power Source Types
Hardwired Motion Sensor Light
Hardwired motion sensor lights are powered by AC voltage, and this type of motion light should be your first consideration when you have wirings available because the hardwired power supply is more solid, consistent and stable that can output ample illumination, and you don’t need to worry about the power once correctly set up.
For outdoor lights, you should always consider wiring the light whenever possible because outdoor lights, especially security lights, consume a lot of electricity to be able to provide the most bright illumination around 3000 to 5000 lumens with consistent performance. If the illumination is not bright enough, it makes no sense to use it as the security light.
Wireless lights need to balance the battery lifespan so the illumination cannot come even close to wired light. You usually need to replace the batteries within one year of usage, even when the light is not frequently activated.
For indoor motion sensor lights, hardwired is not necessary as you can replace the batteries anytime. And the wirings are usually not available where you want to put the motion sensor light, such as under stairs or inside your closet.
Battery Operated Motion Sensor Light
Battery-operated motion sensor lights are wireless that they often use 3 or 4 D-cell batteries for power supply. With an average use of 8 to 10 activations per day, the battery-powered motion sensor lights can usually last for 1 year before the batteries run out.
To have the optimal balance of the battery lifespan and illumination brightness, the battery-operated lights often illuminates around 500 lumens which is enough for common indoor and outdoor use.
Without the requirement for wirings, you are free to place battery-operated motion sensor lights anywhere it’s needed. Commonly the outdoor motion sensor lights are screw mounted to the wall to withstand hard weather like a strong wind. Indoor motion sensor lights are more flexible to install, and they can either screw mounted to the wall traditionally or stick to the mounting plate magnetically.
This type of light that is stick mounted is called the stick-anywhere type. The stick anywhere type light provides a mounting plate to be attached to any wood or metal surfaces by adhesive tapes, and the lights can directly stick to the mounting place magnetically. The sticky anywhere type battery-powered motion sensor light is extremely popular for indoor use.
Solar Motion Sensor Light
Solar motion sensor lights are wireless as well and they do not require extra batteries or wirings for power supply. The solar-powered lights absorb sunlight during the day and charge the electricity into a battery built-in to the lights for illumination at night.
Solar motion sensor lights are trendy for outdoor use because they nearly have no restriction for power or installation, use only green power and have no additional cost except for the purchases of the lights. The solar motion sensor lights are very budget-friendly, and they are often sold in packs to be placed at different corners of your backyard for broad coverage.
If you have sufficient sunlight in your area, the solar lights are the best option for outdoor lighting if you only look for proper illumination for outdoors at night and do not require the light to be consistent and reliable at a security level.
Plug-In Motion Sensor Light
Plug-in motion sensor lights are popular among indoor night lights, which are directly plugged into the wallbox outlets for power.
They are easy and quick to use and have a consistent power supply for bright illumination. If you have available outlets where you want to install the night lights, the plug-in type of motion sensor light might be the best option.
Indoor Motion Sensor Light Applications
For most people, indoor motion sensor lighting is achieved via a motion sensor light switch, but motion sensor lights are also very popular and widely used in many places. The motion sensor lights are a perfect complement to motion sensor switches for small and compact areas where the main lighting cannot cover effectively.
Inside Closet, Cabinet and Drawers
Motion sensor lights are the perfect lighting for compact areas such as closets, gun safes, cabinets or drawers. These compact places are often packed with stuff that cannot get enough illumination inside even when you turn on the main ceiling light in the daytime.
Let alone there are often times you need to use them at night with the ceiling light off. For example, you might need to find something in the drawer but don’t want to turn on the light to wake up your spouse, or you need to find a gun in your quick access gun safe at the bedside but you don’t want to alert the burglars by turning on the bedroom light.
A motion sensor light is the best solution for these spaces. As soon as you open the door, the motion sensor light will turn on to light up the inner room for you to find your clothes, guns, keys, or other small things. After you close the door, the light will automatically turn off to save energy. A wireless battery-operated, stick-anywhere motion sensor light is even better that you don’t need to worry about wiring or installation.
Under Cabinet and Stairs
The space under cabinet, cupboard or stairs are usually covered in shadow because the illumination from the ceiling is often blocked by the cabinets themselves. For example, when you are cooking in the kitchen, the countertops might not have bright illumination that the lighting is blocked by your body and the cupboard. In this case, an under cabinet light such as a strip light or a LED light bar installed right under the kitchen cabinet can provide sufficient illumination for you.
Another reason why it’s better to use a motion sensor light instead of a regular light is that it’s often not convenient to manually operate the lights in these situations. For example, your hands might be too oily or not clean to turn on/off the under cabinet light when you are in the middle of cooking, and the motion sensor strip light under your stairs should turn on automatically to light up the stairs when you come near.
Under-cabinet lights are famous for their ease of installation as well. These under cabinet lights usually have a built-in magnet that users can stick the light directly to any iron surface. For other non-magnetic surfaces like wood cabinets or wardrobes, a steel sheet is usually provided along with the light, so users can stick the iron sheet to the wood surface with adhesive tapes first and attach the motion sensor light to the steel sheet magnetically.
Motion Sensor Night Light
Motion sensor night lights aim to provide illumination at night. Traditional night lights keep ON all night which causes a massive amount of energy waste for lighting up the space with no beneficial use. People might need the illumination from night lights for only minutes per day, and sometimes we don’t need to use the night light at all.
With a motion sensor night light, you can save those wasted energies from now on. Even if you do need illumination all night, some night lights allow you to keep the light dimming on all night and turn 100% on when it detects people to have the best of both worlds into one.
Plug-in type night lights are popular for their quick install and consistent power supply, and there are usually outlets available where you need to place the night light. If you do not have a light socket available or the plug-in type might take too much space, you can use a battery-operated night light instead, making little to no difference.
Outdoor Motion Sensor Light Applications
Outdoor motion sensor lights are mainly for illumination for your backyard or garage around your property and security purposes to detect and deter crimes and intruders. The outdoor motion sensor lights are usually firmly screw-mounted into walls and are weather-resistant to withstand weather elements such as strong wind, water, rust and corrosion. They can be either hardwired, battery-operated or solar-powered according to how you want to power them.
For Illumination and Home Decoration
All outdoor motion sensor lights can provide motion-activated illumination for your property at night. These motion sensor lights can welcome you home by lighting up the backyard and pathway. Some motion sensor lights with warm light, especially the porch lights, can contribute the lighting atmosphere a lot to your home decoration as well.
The motion sensor floodlight and spotlight are widely used specifically as security lights, and they project a strong beam of light to spot any human appearing around your property. Some security lights work in conjunction with a security camera for recording any suspicious activities around your house that can alert you via your phone.
How to Choose the Best Motion Sensor Light
Here are the major things to consider when you want to buy a motion sensor light that will work best for your home.
The brightness of motion sensor light is often identified as lumens, and the higher lumens, the brighter the light is. Lumen, also known as brightness or light output, measures the total quantity of visible light emitted by a light source per unit of time, weighted according to the human eye’s sensitivity to wavelengths of light.
For example, 730 lumens equals a 60 watts light bulb or a 7 watts LED Light. 1500 lumens equals a 120 watts light bulb or a 15 watts LED Light.
Depending on what type of application and how bright you need the place to be, you should look for the lumens of the light can output before purchase.
The power source is another critical factor to look at when choosing a motion sensor light. Many manufacturers would offer several power supply options for the same motion sensor light model, so users are free to choose from wired, battery-operated or even solar-powered as they prefer.
The hardwired and plug-in types of light are powered directly from the source. These types of lights can output consistent and bright illumination. If you have wirings or sockets available, you could consider picking these two types of lights first.
If line wires are not available or difficult to handle, a battery-operated motion sensor light is maybe the only option. The solar-powered motion sensor light is also a great choice when used outdoors.
Where do you want to install the motion sensor light, indoors or outdoors?
For indoor lights, there are not any limitations on where to use what lights. Literally, you can almost use any type of motion sensor light wherever you like. The strip light, night light, stick-anywhere light are usually interchangeable for installation, and it’s totally up to the homeowner to decide which type of light suits their needs best.
For outdoor lights, there are more things to consider such as the detection angle and coverage so they can illumination the entire backyard around your property.
The detection angle from 180 to 360 degrees and detection range from 10 to 20 feet might be suitable for most houses. The fewer detection coverage, the more lights you need to group together to light up the entire space outside your property.
For outdoor lights, you can choose floodlights or spotlights for more of a security purpose and use porch lights and light bulbs for pure illumination and home decoration.
If you have a smart home ecosystem such as Alexa, HomeKit or SmartThings, you can buy a smart motion sensor lights from brands like Ring to connect the light to your doorbell, camera or indoor lights in the ecosystem and control them via phone app.
Where to Place Motion Sensor Lights
Indoor motion sensor lights are usually placed where the ceiling light’s illumination cannot effectively cover, such as under stairs, cabinets, cupboards or inside the compact rooms like drawers, clothes, gun safes.
You can also place the outdoor motion sensor lights wherever needed, whether for illumination at night or security detection for burglars. Common places we recommend to install the lights are: above the garage, walkways, all home entrances including front/back doors and windows, and open areas around your house.
Generally, it’s recommended to install the outdoor motion sensor light 6 to 12 feet for the best motion detection result. The average man height is about 6 feet and the 12 feet is about the max accurate detection range of a standard PIR motion sensor. The installation of different motion sensor light models may vary. Check the installation recommendations from the manufacturer before installation.
When placing the motion sensor light, ensure that the motion sensor points to the area you want to detect, such as doorways or entrances. Additionally, according to how the PIR sensor works, a PIR motion sensor is more sensitive to movement across the sensor and less sensitive to the movement towards or away from the sensor. It’s better to place the motion sensor lights at each side, pointing to the entrance for the best detenting performance.
How to Install a Motion Sensor Light
Installing or replacing your existing light with a motion sensor light is no difference from installing a regular light. The motion sensor does not make a difference to how the light is wired. Check our detailed installation guide on how to install a motion sensor light.
How to Adjust a Motion Sensor Light
After successfully installing a motion sensor light, users need to adjust the settings of the motion sensor light before using it. When the light is not properly adjusted, the light can provide false ONs or false OFFs, which may cause more inconvenience than the benefits it should provide.
Before putting the light into work, we need to adjust:
- Mode: Choose the motion detection mode that best suits your needs, such as auto mode, dusk to dawn mode or manual mode, etc
- Sensitivity: Adjust the sensor sensitivity or detection range so the motion sensor light is not too sensitive or too clumsy
- Timer: Customize the timer on the light so the light is not lasting either too long or too short
- Direction: Point the motion sensor to the detection zone and point the light to the illumination zone
Motion Sensor Light FAQ
How to Keep Motion Sensor Lights On
If you want to keep your outdoor motion sensor light on, for example, leave the outdoor lights ON all night long to illuminate your yard, you should consider buying a light available with such a feature in the first place.
Most dusk to dawn motion sensor lights allow you to keep the light on all night, and other motion sensor lights might provide a manual override feature that allows you to manually keep the light on.
If your current light does not have such features but has a switch to turn ON/OFF the power, you can try to turn the light ON, OFF, ON quickly to override the motion sensor and keep the light on. This method will work for some motion sensor lights, worth a try.
If you have electric skills, you can manually add a switch parallel to the lights to power the light individually by simply taking the hot circuit to the sensor and to the light switch in parallel. So you can use the light switch to always power the light and keep them on, but you are not able to turn the light off manually when the motion sensor has been detecting motion and powering the light on its side.
How to Turn off Motion Sensor Lights
If your motion sensor light does not have a manual override feature, then you have to wait for the timer(time delay) to expire, and the light will automatically turn off.
If you want to keep the light off, you can disable the motion detection function on the light if it’s able to do so. Or you can completely mask the motion sensor to keep the light off as the sensor cannot detect motion.
How to Fix a Motion Sensor Light That Stays On
First, check whether the light is set to Always On mode. For example, some dusk to dawn motion sensor lights allow you to keep the light on all night with one of its working modes. Try switching to motion detection mode and see if the light can turn off.
If your light still stays on, it’s possible that the motion sensor is constantly detecting motion that you are unaware of, such as the moving cars or heat sources near the light. Try pointing the light to other positions or masking the motion sensor to see if the light is still on. If the light can auto turn off when facing other directions, then it’s highly possible that the motion sensor has been detecting distraction heat sources.
Another reason is that the timer is set too long that it seems the light stays on without turning off. Try setting a minimum time delay, such as 20 seconds to see if the light will turn off.
Finally, the motion sensor might get overridden, so the light is always powered. Unplug and reset the light to see if it will get back to normal.
Why Are Motion Sensor Lights Flashing
When your motion sensor light keeps flashing ON and OFF and flickering, it’s usually not the problem of the motion sensor because the PIR motion sensor used on the lights is very durable and will keep the light ON for a while and does not simply switch from ON and OFF instantly.
The repeatedly flashing is often caused by the light bulb and electric circuit. Check the following for possible causes:
The light bulb is bad. It is the most straightforward reason that causes the flickering. Try replacing it with another light bulb.
The connection between the light bulb and the light fixture is not stable. Try reinstalling the light bulb.
The circuit itself is faulty, which may also cause the light to turn ON by itself, bypassing triggering from the motion detection. Try replacing it with a regular light fixture to see if it flashes as well.
How to Reset a Motion Sensor Light
Fully unplug the light or turn off the breaker for at least 30 seconds, then most motion sensor lights will be successfully reset to the default setting.
Can Animals Trigger Motion Sensor Lights
Yes, as most outdoor motion sensor lights utilize PIR motion sensor, which detects motion by infrared, or simply put, heat changes, so animals can trigger the lights if they have near-human body temperature.