Pros and Cons of Wired and Wireless Motion Detectors

You don’t want to take chances with your home security system.

Motion detectors are small devices that send notifications any time there are people near or inside your home who shouldn’t be there. Sensors can help protect your home and give you peace of mind.

With so many motion detectors to choose from (both wired and wireless), it can be tough to decide which kind will work best for you.

This guide reviews the differences between wired and wireless motion detectors. We’ll explain how they work, run through the benefits and disadvantages of each, and answer some common questions about motion detectors.

How do motion detectors work?

A motion detector's main job is to sense when there’s movement in or around your house. Your devices will either send you notifications using a mobile app, set off a motion sensor alarm, or activate another device in your security system whenever they detect burglars or intruders on your property.

Different motion detectors work in different ways. The two main types of motion detectors are active ultrasonic sensors and passive infrared (PIR) sensors. Here’s a breakdown of how the technologies work.

Ultrasonic sensors rapidly emit sound waves from a transducer within the device. These sound waves are too high to be heard by the human ear.

An echo of the sound wave bounces off objects surrounding the motion sensor and travels back to the transducer. The transducer measures the time it takes for the wave to leave and come back and uses the calculation to measure the object’s distance.

This process happens constantly. If the amount of time it takes for an ultrasonic sound wave to echo back to a transducer changes, the sensor knows that something is moving.

PIR sensors are more advanced. They can measure the heat, or infrared radiation, given off by objects and living things in an environment. Infrared sensors know something is moving when they notice a change in the temperature of their environment.

Both ultrasonic sensors and PIR motion sensors work well indoors. However, ultrasonic sensors can get confused by objects (like furniture) in your home. And ultrasonic detectors don’t work well as outdoor motion sensors because small animals and bugs can set them off.

While PIR sensors work better inside, they can sometimes be a component in outside security cameras. It’s also harder to confuse PIR sensors because they don’t rely on waves bouncing off an object.

Active ultrasonic sensors and PIR sensors are the most common forms of motion sensors, but there are a few other technologies. For example, area reflective sensors detect motion by bouncing LED light pulses off objects, and vibration sensors can tell when objects vibrate.

There are even dual-technology sensors that combine two types of sensors to minimize false alarms.

Pros and cons of wired motion detectors

Wired motion sensors are usually wired into your home’s electrical system and rely on your home’s wiring for power and to send messages to other devices in your security system.

For example, when a wired motion detector senses movement, it might send a signal down an ethernet cable or phone line in your home to your security camera. The security camera would then record in the area.

Here are some advantages of using wired motion detectors:

• Wired motion detectors are reliable. Signals that travel within a wired system in your home aren’t likely to get lost.
• Wired motion detectors are secure. Wired systems are difficult for cybercriminals to hack because they don’t normally rely on a wireless internet connection.
• You don’t have to worry about replacing the batteries in wired motion detectors because they use your home as a power source.

Here are some disadvantages of using wired motion detectors:

• Wired systems can be complicated to install because they have to be tied into your home’s existing electrical network.
• If you have plug-in sensors, they’ll need to be near an outlet. This can severely limit where you can place them.
• You can’t take your motion detectors with you if you move (unless you’re willing to completely disconnect them from your home’s wiring system and reinstall them in your new home).

Pros and cons of wireless motion detectors

Wireless motion detectors work using your Wi-Fi internet connection or a cellular network to communicate with your home’s security system. They’re also generally battery-operated.

Here are some advantages of using wireless motion detectors in your home:

• Wireless sensors are much easier to install than wired ones because they don’t need to be tied into your home’s electrical grid.
• Wireless sensors can send alerts to your smartphone while you’re away. You can monitor and control security systems that use Wi-Fi technology remotely.
• If you move, you can simply pick up your detectors and take them with you.

Here are some disadvantages of using wireless motion sensors:

• Sensors that use wireless internet can be susceptible to hackers. It’s crucial to use strong passwords to protect your Wi-Fi network if you have wireless sensors.
• Signals sent through Wi-Fi networks can get lost easier than those sent over a wired network.
• Wireless motion detectors use batteries. You’ll need to change them periodically.

Wired or wireless: Which motion detector is best for you?

Many different factors can help you decide whether to go with wired or wireless motion detectors in and around your home. Here are some of the top things to consider when choosing a motion detector alarm.

• Your location: If you live in a rural area where Wi-Fi internet can be spotty, you might want to use wired motion detectors to get better reliability.
• Whether you rent or own your home: Wired motion sensors might not be an option for renters because they require drilling into your home’s walls to reach its electrical system.
• Your installation: You’re better off going with wireless sensors for easy installation. You should have a professional install wired detectors if you don’t have experience with electrical systems. Even if you have wireless detectors, an expert can show you the best places in your home to mount them.
• Your other smart connected devices: Smart motion detectors can connect to the rest of the smart devices in your home. Many of today’s smart appliances connect to each other using wireless technology. Wireless sensors may be able to connect to smart home hub systems like Amazon Alexa as well.
• Whether you want remote control of your sensors: You can control and keep tabs on smart wireless sensors from anywhere through a mobile app.
• Your budget: Wireless sensors generally have a higher price tag than wired ones. Account for the cost of professional installation for wired sensors when weighing your options.

Motion detector FAQs

We’ve provided answers to some of the most common questions people ask about motion sensors.

Do motion sensors use Wi-Fi?

Wireless motion sensors can use Wi-Fi internet or cellular networks to communicate with other devices in your home security system. Wired sensors generally use your home’s landlines or ethernet cables to work.

Can I use my phone as a motion detector?

While mobile phones can’t work as motion detectors themselves, you can use your phone to manage your smart motion sensors. For example, a Vivint smart home security system allows you to program smart devices like motion sensors and get notifications from anywhere using your phone.

Do all security cameras have motion detection?

Many security cameras have features like motion sensor lights to monitor an area. For example, video doorbells like Vivint’s Doorbell Camera Pro have sensors to detect when someone comes near your door and sound a chime to notify you.

However, security camera sensors might not be as effective as dedicated motion detectors. In a smart security system, your motion detectors can communicate with your security camera directly.

For example, you could program your indoor security camera to turn on whenever the detectors in your hallways sense a person.

See how Vivint brings motion detection to the next level

Motion detectors are an essential piece of an effective home security system. If you’re ready to upgrade your home protection game, take a look at the motion sensors offered by Vivint. While there, be sure to check out all the other great smart security devices we offer.

Our motion detectors have many advanced features. They’re pet immune, have a large detection range, a two- to five-year battery life, and integrate with a variety of other smart devices and home automation software (like smart lights, smart locks, and weatherproof outdoor security cameras).

Vivint’s security alarm system makes it easy to protect your home from wherever you happen to be. Call us at 855.822.1220 to speak to one of our smart home experts. They’ll be happy to walk you through the process of designing your ideal custom smart home setup.