What Are Common Components of a Security System?

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Alina Bradford
May 02, 2023
Icon Time To Read2 min read
Icon CheckReviewed ByRebecca Edwards

With 25+ years in tech journalism, Alina blends safety expertise with her passion for simplifying technology. Alina has tested hundreds of safety and security devices, is trained as a first responder, and has worked as a volunteer firefighter.

A DIY or professional security system consists of different components, including motion sensors, indoor and outdoor cameras, glass break detectors, door and window sensors, yard signs and window stickers, smoke detectors, and carbon monoxide detectors. These alarm system components work together to keep you and your family safe from a variety of threats.

Whether you just want to learn more about security system parts or are considering going the DIY route, here are the major security system components you should be aware of.

Motion sensors

Motion sensors are an essential part of any home security system. They have a wide variety of uses: turning on indoor and outdoor lights, activating cameras, setting off alarms, and more. For this reason, they are often incorporated into other home alarm system equipment.

Indoor and outdoor cameras

Glass break detectors

Security cameras are another core part of the security system. Cameras can be used to record areas of your home or yard, and some can also send the feed straight to your smartphone or tablet.

Cameras are also used in new and clever ways, from doorbell cameras that are all but invisible to smart cameras, like the Google Nest Cam (Battery), that record in crisp 1080p HD and automatically store footage in the Cloud for safekeeping.

Glass break detectors are handy sensors that detect the frequency of shattering glass and set off an alarm. These are useful for letting you know if someone attempts to enter your home by breaking windows or glass doors, making them an essential component of an alarm system.

Typically, these small sensors are placed indoors near windows or other glass you’re concerned about someone breaking. They tend to be inexpensive, so they make great, simple investments to boost security.

Door and window sensors

Door and window sensors detect when the door or window they are attached to opens. These devices use two sensors: one on the door or window, and one on the frame.

When the door is closed, the two sensors form a closed circuit. When the door is opened, the circuit breaks, triggering a burglar alarm or text alert.

This is an older technology, but it works. And like glass-break detectors, they tend to be inexpensive, making them great first investments in home security.

Yard signs and window stickers

One burglar alarm part that might be easily overlooked is the signage that comes with it. You might not think these are all that important, but the presence of these signs and window stickers can deter would-be burglars from entering a home. Make sure to display your signs prominently!

Smoke detectors

Most homes have smoke detectors installed, but if you need to install your own, you can get one as part of a comprehensive home security system. If you’re looking to upgrade, there are also smart smoke detectors that speak alerts out loud, letting you know what room the smoke is coming from.

Carbon monoxide detectors

Carbon monoxide (CO) detectors are less common than smoke detectors, but they are just as important. Carbon monoxide is odorless, tasteless, and colorless. Without a detector, there is no way to know this gas is present. This can be extremely dangerous—thousands of people go to the hospital each year from CO poisoning in their homes.

You can get smoke detectors with built-in CO detectors. This can help you save money on home security equipment. 

 

This covers the basics of a security system. If you’re considering purchasing a home security system, check out our picks for the best options.

Compare the best home security systems

Brand
Self-monitoring option
Monthly cost Icon Tooltip  Dark
Starter equipment price
Break-in deterrent(s) Icon Tooltip  Dark
Smart home compatibility Icon Tooltip  Dark
Learn more
Icon No  LightNo
$0.00Smart AI detection, Live agent intervention, Motion-sensor floodlight camera with two-way talkGoogle,
Z-Wave
Icon Yes  LightYes
~$250AI detection, Live agent intervention, Siren, Cameras with two-way talkAmazon,
Google
Icon No  LightNo
~$200.00Smart Deter lurker detection, Lights, Sounds, Motion-sensor floodlight camera with two-way talk Amazon,
Google,
Z-Wave
Icon No  LightNo
~$300Motion-sensor floodlight camera with two-way talkAmazon, Google
Icon Yes  LightYes
~$200Live agent intervention, Lights, Siren, Motion-sensor floodlight cameras with two-way talkAmazon, Z-Wave
Icon Yes  LightYes
~$75AI-powered alerts, Cameras with two-way talkAmazon, Google, Apple, Z-Wave, Zigbee
Icon No  LightNo
~$400†AI-powered alerts, Lights, Siren, Cameras with two-way talkAmazon, Google, Z-Wave

Amazon.com price as of post date. Offers and availability may vary by location and are subject to change. Read full disclaimer. *ADT $28.99 for landline system only. Full ADT disclaimer  Frontpoint's starter equipment package, valued at $386.93, starts at $69 with an optional contract.

Alina Bradford
Written by
Alina is a safety and security expert with over 25 years of experience. She has contributed her insights to CNET, CBS, Digital Trends, MTV, Top Ten Reviews, and many others. After testing thousands of devices, apps, services, and more, her goal is to make safety and security gadgets less mystifying one article at a time. In the early 2000s, Alina worked as a volunteer firefighter, earning her first responder certification and paving the way to her current career. Plus, she has tested hundreds of pieces of security and safety equipment over the years. Places published: CBS, MTV, CVS, Rachael Ray, eBay, Reader’s Digest, ConsumerAffairs, and more. Certifications: Fire Service Training, Oklahoma State University. Awards: Received the Experience Leader certificate from Authority, putting her “in the top 25% among the thousands of professional content creators analyzed by Authory for the Fall 2023 audit.” You can view more of Alina's work at alinabradford.com.

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