What Are Common Components of a Security System?

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A home 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.

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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

Security cameras are another core security system part. 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

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

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’s one that works. And like glass break detectors, they tend to be inexpensive, making 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.

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

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Celeste Tholen
Written by
Celeste Tholen
Celeste has dedicated her decade-long career to reporting and reviews that help people make well-informed decisions. She oversees editorial strategy and production for SafeWise, with a goal to help everyone find the information they need to make their homes and lives safer. Prior to SafeWise, she worked as an editor and reporter for KSL and Deseret News. She holds a Bachelor's degree in Journalism. In her free time, she volunteers at the local botanical garden and writers for the community newspaper.

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