How Do Pet Immune Motion Detectors Work?

Motion sensors guarantee additional home security by sending alerts when someone or an abject crosses designated areas inside your home. Moreover, they perfectly complement an existing safety system if you combine them with indoor wireless security cameras.

Currently, manufacturers build motion detectors for homes with pets, allowing homeowners to adjust the sensitivity range. So, they do not recognize dogs and cats, causing false alarms.

However, these customized motion detectors only work efficiently with proper installation and configuration.

In addition, understanding how the devices work is essential if you want the best from them. Therefore, let’s answer a common question: How Do Pet Immune Motion Detectors Work?

Pet immune motion detectors ignore movements from objects behaving like pets. Besides, they use the object’s weight as a dominant indicator to differentiate humans from pets.

As a result, the sensor does not trigger when a pet weighing below 80 pounds is in the monitored area.

Though sensors’ specifications vary depending on the manufacturer, most devices work with 40 to 80 pounds. So, consider your pet’s size and weight to get the most suitable detector.

There is so much more to learn about these pet immune motion detectors. Furthermore, you must know where and how to position them for optimal functionality. Hence, read this article carefully as it discusses pertinent issues concerning these devices.

What Is a Pet Immune Motion Sensor?

How Do Pet Immune Motion Detectors Work?
A Pet Immune Motion Sensor

Generally, pet immune motion sensors are specialized detectors that detect pets and avoid false alarm triggers. They use algorithms and weight, height, movement, and speed datasets to distinguish pets from other intruders. As such, the device triggers due to every movement but pets.

These sensors detect upright humans walking upright and ignore small animals walking close to the floor. Thus, properly mounting and positioning them is essential for optimal functioning.

Moreover, manufacturers provide manuals on how to mount these units for easier installation.

Remember, pet immune motion sensors allow pets and small animals to move around your home freely without annoying false alarms. At the same time, the device detects people moving in the target area.

So, you’re basically benefiting from both worlds: Allow your pets to play freely while guaranteeing maximum security to your property.

Some manufacturers consider these motion sensors “Pet-Friendly” rather than “Pet-Immune.” They even argue that there is no such thing as “Pet-Immune” motion detectors.

Well, they are not far from the truth. Bigger pets and moving inanimate objects, such as holiday decorations and balloons, trigger the alarm if they come within six feet of the motion detector.

Thankfully, these “Pet Friendly” motion sensors allow you to decrease their sensitivity, mount them at least seven feet from the floor, or partially mask the lens that looks downward at the floor. 

A typical motion detector is not smart enough to determine whether the detected motion is from a dangerous criminal or pet. Hence, some pet immune motion sensors have two detention patterns. 

The first one features a lower pattern that looks closer to the ground where pets move. Next, the device has an upper pattern focusing on where people walk upright. Therefore, the motion sensors only activate when both detention patterns are triggered.

Interestingly, most pet immune motion detectors offer pet immunity for pets up to a certain weight. For instance, if the gadget provides pet immunity for up to 40 pounds, small animals above this weight will activate the sensor.

However, these listed weights are usually estimates. The primary consideration is whether the pet gets within the detector’s field of view.

Also, pet immune motion sensors are not 100 percent perfect. The pet triggers the alarm if it gets in the upper detection area.

For example, if your pet climbs on a couch facing the motion detector, it will activate and trigger the alarm.

As a result, reconsider the pet immune motion sensor’s location and settings. Mount it at a proper height, say 7.5 to eight feet high, and use the lowest detection sensitivity level possible.

Pros and Cons of Pet Immune Motion Sensor

Every homeowner prioritizes property and family members’ protection. Therefore, it is crucial to search for efficient ways to improve your home’s safety.

A pet immune motion sensor is one of the foolproof ways to safeguard your property while enjoying the presence of adorable pets. Below is a detailed account of the device’s pros and cons for better decision-making. Starting with the pros:

1. Improved Safety and Home Security

Pet immune motion sensors are still motion detectors that alert homeowners when burglars, criminals, and vandals access their property. 

Further, these unwanted guests attempt break-ins when homeowners are asleep or away. Therefore, the gadgets deter them from focusing on your property by triggering the alarm or activating outside lighting.

Moreover, humans are not the only creatures you want safety from. Depending on your home area, Flora and fauna pose a risk to your family members and pets. For instance, coyotes, mountain lions, bears, and raccoons may approach your facility for food.

But the alarm or outdoor lighting fixtures will scare them away once they reach the targeted area.

Pet immune motion sensors are particularly beneficial when you stay in areas with bloodless winters. Besides, the lighting comes on as soon as you enter your compound. This way, you easily navigate slick floors with ice and snow, extensively lessening the probability of injury.

2. Improved Convenience

Pet-immune motion sensors allow homeowners to attach light fixtures that respond to system triggers. The lighting comes on when you pull into the driveway, giving you ample time to park and offload the car.

In addition, the porch light switches on when you step into the area, so you do not fear running into objects while approaching the door, or you can comfortably do tasks on the driveway.

3. Energy Savings and Cost Savings

Pet immune motion sensors only activate outside lighting fixtures after detecting movement from larger animals and humans. Hence, they eliminate the need to keep the lighting on 24/7. As a result, your household extensively reduces its power consumption.

Moreover, these gadgets are the best alternative if you do not want to always keep your driveway, porch, or other exterior lighting on. They consume less power while guaranteeing superior protection and comfort.

Unfortunately, pet immune motion sensors have disadvantages like all other electronics, making them unsuitable for various applications. These con include

1. Very Sensitive in High Temperatures

Passive infrared pet immune motion detectors sense any temperature increments within the sensory coverage. Thus, they react to any motion sensed within ten to fifteen meters.

In addition, the devices react to any heat changes, no matter how insignificant, when installed near heaters and air conditioning units. As a result, you experience reduced light effectiveness and false triggers.

Some pet immune motion sensors struggle to function in conditions above 35 degrees Celsius. Therefore, they do not work optimally in warmer climates, especially if the temperature does not drop at night.

2. A Bit Insensitive to Slowly Moving Objects

Unfortunately, passive pet immune motion sensors are less sensitive to objects moving slowly or toward them. Besides, intruders aware of this aspect move slowly or directly toward the device, preventing any triggers.

How Do Pet Immune Motion Detectors Work?

Pet immune motion sensors typically function by overlooking movement signals from objects behaving like pets. Furthermore, they use weight as the dominant indicator to differentiate pets from humans.

The detector does not trip when the pet weighs below 80 pounds, but this condition depends on the device’s specifications.

However, though the product’s features vary by manufacturer, most sensors ignore pets weighing 40 to 80 pounds. Anything above this stipulation is considered a human being and trips the sensor.

Pet immune motion detectors use the same lens as standard motion sensors. In addition, they pick up heat signals and motion patterns from the targeted area to detect intruders. The difference is that the gadgets have different sensitivity, calibration, and detection capabilities.

Moreover, small pets’ average height functions as a low-sensitivity zone for these motion detectors. For instance, the detector does not trip if an item in the targeted zone matches the prescribed weight and other indicators.

Thus, mounting a pet immune motion detector is critical for minimizing false alerts.

Again, pet immune sensors are not immune to pets by nature. So, they require special care during mounting. Otherwise, incorrect mounting results in hundreds of annoying false alarm frowns from family members and neighbors and even a fine if it persists for a long duration.

You may wonder if the pet immune detector can detect someone crawling on the floor. In addition, does the gadget consider a person’s weight greater than a small dog or cat?

Remember that weight is not the only detection indicator for pet immune sensors. They use metrics such as movement patterns, speed, and height with other specialized algorithms to separate pet from human movements.

Therefore, a human crawling past the pet immune motion detector will not succeed as most indicators would fail to meet.

Since these devices require correct installation to function as desired, work closely with the manufacturer’s guide to deliver the best outcome. And follow the quick tips below to start your home protection journey.

1. Choose an Optimum Height

Ensure that your pet’s immune motion sensors are 7.5 to eight feet high. Any height below this compromises the sensitivity area.

Besides, the pet may not fall under the low-sensitivity lens area and trigger the detector.

Consequently, stairways are unfavorable places for pet-immune motion detectors. If pets come crawling up, they’ll interfere with the sensors’ field of view, causing a false alarm.

2. Adjust the Sensor’s Sensitivity

Pet immune detectors should be low-sensitivity to avoid capturing pets. Furthermore, the devices use pulse counts to determine area coverage and sensitivity.

For instance, higher pulse counts indicate a larger being, especially a human who covers a larger section. On the other hand, a lower pulse count covers smaller regions where pets fall in.

Use low pulse counts for the pet immune motion sensor to prevent pets from triggering it. Moreover, if you suspect the sensitivity is too low, switch it to medium. Then, configure an adjustment that works for you.

3. Evaluate the Unit’s Mount Point, Angle, and Position

Ensure there are fewer heat sources around the detector, especially if it uses infrared radiation. Sunlight, lighting, and radiators cause false triggers, so pick an area with low interference from other objects.

In addition, ensure the sensor’s angle is not too low, as it shortens the field of view. Ultimately, the low-sensitivity region becomes too short for it to ignore pets.

Positioning the sensor away from your pet’s reach is another way to minimize false alarms and enhance its efficacy. Otherwise, the pets will activate the sensor when they climb it or attempt to walk on their hind legs.

Finally, a perfect position is at the optimal height, covering areas and angles where only humans pass through.

Below is a brief placement checklist for easy device installment and management.

  • Place the pet immune motion detector in a high corner of the room, say six to eight feet from the floor. This way, they cover as much surface area as possible.
  • Avoid placing the devices near a window or door, blocking their range.
  • Avoid aiming the motion sensor toward fireplaces, area heaters, forced air heating vents, and air conditioners.
  • Avoid placing these gadgets in direct sunlight, as sudden temperature increments trigger false positives.
  • Avoid placing pet immune motion sensors near ductwork or other metallic objects affecting RF signals.
  • Avoid positioning the unit outdoors or in non-temperature-controlled areas.

Will Larger Pets Trigger the Pet Immune Motion Detector?

Yes, larger pets trigger the pet immune motion detector as their height and weight do not meet its requirements. Generally, most sensors successfully ignore pets below 80 pounds. So, your pet may trigger the sensor if it weighs more.

Although you can reduce the motion sensor’s sensitivity to avoid detecting larger pets, it’d be counterproductive against humans.

Remember that the primary goal of a motion detector is to detect intruders and criminals. Thus, pet immune sensors feature a trade-off between effortlessly identifying humans and avoiding pets.

Sometimes, you may give up on security systems with motion detectors when you have furry friends at home.

Thankfully, installing the safety unit can keep your facility secure without triggering an alarm every time your pet passes close to the motion sensor.

Further, consider the following ideas when mounting pet-immune motion detectors. They’ll come in handy when controlling larger pets prone to triggering the alarm.

1. Position Your Motion Sensors Above the Waist Level

Generally, pets spend most of their time on the floor. Therefore, placing your motion sensor above waist level, say four to five feet above the ground, helps keep these animals from activating false alarms.

Alternatively, consult a home security expert for advice on where to mount the motion sensor when you’re concerned a trespasser could break into your property.

Moreover, they’ll assist in deciding where to place it for maximum home coverage without your pet triggering the alarm.

This trick requires you to check whether your pet is out of range and arm the security system in test mode. But it may not work well when your pets frequently jump on furniture.

2. Choose a System You Can Control Remotely

Larger pets easily trigger motion detectors, requiring you to choose systems you can monitor through an app. Besides, you can check the home’s cameras to determine whether the detected movement was due to an intruder or your pet.

As a result, you’ll prevent accidental trips, intervene, and disarm the security system before it alerts the police.

3. Use Window and Door Sensors

Most motion detectors detect intruders inside your house, but how about one that alerts you when they try to get in? Door and window sensors are effective as motion sensors and cannot be accidentally triggered by pets.

Security detectors positioned on doors or windows alert you when they’re opened while the unit is armed. In addition, you can use sliding glass doors and glass break sensors on windows, which alert you during a breakage.

So, since it’s unlikely that your pets will open a window or break glass, these motion sensors are perfect for homes with larger pets.

4. Turn Motion Sensors Upside Down

Flipping your motion detectors upside down is a straightforward trick to prevent accidental alarms. This way, they detect motion from a few feet to the ceiling, leaving the area unobserved for your pets to roam around.

Again, a home security expert can help you get the optimal location for your motion detectors to guarantee maximum coverage.

However, this hack may not work well if pets often jump onto cabinets and tables.

5. Choose a Sensor That Filters By Weight

Unfortunately, pets accidentally trip security detectors all the time. Hence, new technology in this field is handy since it allows you to filter out motion.

Thus, advanced sensors ignoring objects below a certain weight are the best for preventing pets from activating the alarm.

However, these motion detectors are only excellent for small pets like dogs and cats. Only pets weighing less than the gadget’s limit can move freely around the home all day.

6. Lower Your Camera Sensitivity

Lowering your security camera’s sensitivity is excellent for preventing accidental trips. The device filters out minor movements, such as a pet rustling around a crate or shifting in sleep. 

However, the camera will still capture significant movements, like walking across or jumping across your home.

Nevertheless, this strategy is better than doing nothing. In addition, your pet may not be as large as you thought.

NB: All motion sensors have a sensitivity feature, allowing you to reduce their sensitivity. As a result, the device will need a more significant heat change to trigger the alarm.

Further, this adjustment is critical when you have bigger pets, an overly enthusiastic dog, and a mischievous cat that can trigger the alarm by jumping higher.

How Do Pet-Friendly PIRs Work?

Pet-friendly alarm sensors are similar to standard alarm systems, except that they depend on a motion detector for activation. The other control panel components are similar to window and door sensors.

The gadgets are also called pet-friendly passive infrared motion sensors, which work by ignoring body heat movement changes up to 30 kilograms.

Also, they check for thermal differences in the target area and trigger an alarm when a human passes.

Small pets like dogs and cats do not emit infrared radiation or alter the targeted area’s thermal levels as humans do, so they do not activate pet-friendly motion detectors.

Both pet-friendly and standard passive infrared motion detectors have larger detection zones. However, the former has enough room underneath for pets to maneuver the area undetected.

Interestingly, this does not mean humans can crawl past the motion detector, as their bodies will emit high infrared radiation and trigger the device.

However, though pet-friendly alarm systems are perfect at reducing false alarms, they are not entirely foolproof. For example, you may experience problems if your dog likes to jump at the window or your cat tends to jump around the monitored area.

But still, the possibility of the pets triggering the alarm is lower than when working with a conventional alarm system. Moreover, you won’t experience issues if your pet weighs under the stipulated pounds.

Conversely, larger dog and cat breeds exceeding the sensor’s limit trigger pet-friendly passive infrared motion detectors. The animals emit more infrared radiation, causing more significant thermal differences in the area.

So, if your large cats and dogs love roaming freely in the house, consider installing other security gadgets, such as window and door sensors. These sensors use a magnet and a reed switch and only activate the alarm when they’re close to each other.

Alternatively, install glass break detectors that detect glass-breaking or tapping sounds to determine forced entry into your property.

Thankfully, passive infrared motion detectors always give a workaround for specific issues. For example, you can use smart alarms with a PIR camera to capture and detect heat movement from pets and people.

Further, these gadgets are smarter than regular pet-friendly PIR detectors and discern whether the moving object is an animal or a human. Better still, the camera sends you snapshots and notifications through a phone app to let you know who triggered the alarm.

This phone application also allows you to deactivate the alarm, examine the captured snapshots, and re-arm the system without going through the control panel. Hence, you minimize false triggers while more effectively securing your home.

Here’s How PIR Motion Sensor Work:

Can a Small Dog Set Off a Motion Detector?

Fortunately, a small dog cannot set off a motion detector, provided it offers pet immunity and is appropriately mounted. Otherwise, any mistakes during installation allow the pet to activate the system, causing a false alarm.

Below are a few guidelines if your small pet triggers the motion sensor.

  • Step One: Confirm It’s Your Small Dog Triggering the Sensor

Something else could cause this issue, not your pet. Thus, confirm whether the motion sensor is near heat sources such as a stove, fireplace, and radiator.

Also, evaluate a theme to the sensor’s trigger. Sometimes, the activation is due to heating set on a timer.

Lastly, check whether the sensor is near a door to a window with direct sunlight hitting the detector.

  • Step Two: Pet-Proof Your Motion Sensors

Proceed to this step after verifying that the above factors do not cause false triggers and alarms. Also, carefully follow the instructions for each pet.

1. Dog. Turn the motion detector upside down with the test dial facing toward the floor. Then, fix it to the wall around four to five feet high, ensuring it’s out of reach for the dog.

2. Cat. Position the sensor on a wall with no furniture below or near it. Then, turn the device upside down with the test dial facing the floor before fixing it four to five feet high.

How Far Does Motion Detector Reach?

Most low-cost motion sensors detect motions at distances of about 4.6 meters or 15 feet. Specialized systems are more pricey and have increased sensitivity and longer ranges.

More specifically, tomographic movement detection systems cover larger areas. They sense radio waves at frequencies that penetrate most obstructions and walls and in multiple locations.

Assess your motion detector and make necessary adjustments. For instance, if the detection zone is too long, aim the sensor’s head down slightly.

On the other hand, if it is too short, raise the gadget’s head but keep it one inch from lamp covers and light bulbs.

When the range is correct, make finer adjustments using the dial labeled sensitivity. Start with the button set at the maximum range before turning it down to shorten the zone. Further, narrow the lens opening with tape if the zone is too wide.

Remember, the above process is trial and error, requiring a few minutes.

You may also need to add narrow blinders only to the left or right ends of the lens. However, only cover as much of the lens as required for the desired effect.

Finally, confirm the zone width and length settings and reset the on-time switch.

Frequently Asked Questions

  • How Do Motion Sensors Work?

Generally, passive infrared motion detectors identify movement or heat signals across their field of view. Then, they trigger the alarm after sensing any motion.

On the other hand, active motion sensors release various wave types to detect objects within the monitored area.

Passive infrared and active motion detectors have flaws you can bypass by combining them. PIR sensors only depend on heat signals, while their active counterparts trigger due to objects reflecting its waves or signals. Therefore, a dual sensor only sets off the alarm when both detectors trigger.

In addition, dual sensors are the best for homeowners with pets since they need more requirements to trigger the alarm.

  • What Are the Types of Motion Sensors?

Motion sensors vary depending on how they detect movement. For example, Passive infrared Sensors identify body heat or infrared energy by assessing temperature changes. Thus, they are famous in most home security systems.

In addition, these detectors create a protective grid to detect heat changes and movement in the surrounding region. 

So, infrared energy levels increase rapidly if a moving object interferes with multiple grid zones, triggering the alarm.

On the other hand, Microwave Detectors send out microwave pulses and measure reflections from moving objects. They cover larger regions than their infrared counterparts but are more susceptible to electrical interference and are pricey.

Dual-technology motion Sensors are another category, combining multiple detection techniques to minimize false alarms. These technologies mainly combine passive infrared sensors with microwave ones.

Each sensor operates at different spectrum levels, ranging from active to passive. Triggering the alarm is difficult because the intruder has to trip both sensors to activate it.

Other less common motion sensors include Vibration Detectors that detect minor vibrations people cause when moving through a room. Also, you’ll find Ultrasonic Motion Sensors that measure reflections from moving objects using pulses of ultrasonic waves.

Finally, Area Reflective Detectors emit infrared rays from an LED. They use the reflection to measure the distance to the intruder, allowing detection when the object moves within the monitored area.

  • How Do I Maintain My Pet Immune Motion Detectors?

Motion sensors accumulate dust and debris over time, interfering with infrared energy transmission. As a result, the device does not pick signals correctly, making it less effective at motion detection.

Therefore, clean motion detectors with a slightly damp microfiber cloth every couple of months. In addition, unmount the unit when painting your walls and replace it if you paint on it accidentally. 

  • How Do Movement Sensors Ignore Small Animals?

Most movement detectors do not assume small animals by default. You must configure the device’s sensitivity to ignore certain areas, temperatures, weights, and heights.

So, calibrate your movement sensor’s sensitivity to overlook animals below a certain threshold.

Larger animals will still trigger a pet immune motion detector since it only filters out smaller ones. Besides, these pets’ weight and height may exceed the low-sensitivity region. Hence, mount and configure other security devices when concerned about frequent false alarms.

  • Will Pets Set Off Motion Detectors?

Pets can set off motion detectors at low heights or that are not correctly mounted. Moreover, most passive infrared sensors pick motion signals from pets.

Thus, consider a pet immune motion sensor to keep them from triggering the sensor.

Thankfully, these detectors are relatively affordable and cost the same as a standard motion sensor. In addition, you can calibrate the device’s sensitivity to match high-sensitivity zones and avoid triggers by small moving objects.

  • How Do I Prevent My Pets From Setting Off Pet Immune Motion Detectors?

Unfortunately, pet immune motion detectors ignore pet movements and reduce false triggers. Thus, factoring in some aspects is essential in avoiding accidents caused by enthusiastic and playful pets. They include

1. Consider the Size of Your Pets. Although pet immune motion sensors ignore pets, they can trigger false alarms under some conditions. 

Further, most pet immune detectors use ratings related to the pet’s weight, but small pets can activate them with enough verticality. So, if your cat or dog loves jumping over furniture and stairs, they’ll set off false alarms.

2. Avoid Overhangs. Overhangs reduce the range of LED motion detector lights or cameras and block the sensor light’s 180-degree sensing angle; in the same way, wearing a hat with a visor or brim dresses up your vision view.

3. Don’t Block the Infrared. Motion detectors are like flashlights, sending out light beams, but they use motion-detecting infrared radiation instead of light waves. These waves cannot penetrate through walls or furniture. Therefore, set up your pet-immune motion sensors so they cover the monitored area.


Pets are an excellent home addition but are frustrating if you have motion sensors and security systems. Besides, cats are problematic as they are more likely to climb to higher areas than dogs and other pets.

As a result, they frequently trigger the motion detector, causing the alarm to go off.

Fortunately, you can program your gadget to detect movement below or above a certain level. In addition, we have pet-immune motion detectors that allow multiple adjustments to reduce pet-related alarm triggers.

So, check out the above article for more insight into these devices and how they work for more convenience.

How Do Pet Immune Motion Detectors Work?

Pet immune motion detectors have the same lens as regular motion sensors. Moreover, they pick up motion patterns and heat signals from the monitored areas to detect trespassers.

However, the difference is that the devices have different detection capabilities, sensitivity, and calibration.

For instance, the detectors use algorithms and height, weight, speed, and movement datasets to differentiate pets from humans. Thus, they activate due to all other movements, apart from pets.

Leave a Comment

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.