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Alarm System Components - The Basics

Basic Components

With so many different types of home alarm and security systems on the market today, choosing one that best complements your budget and lifestyle can be a challenge. An overview of basic components can be helpful when researching any industry and its products, so let’s begin with that. After all, an informed consumer makes the best choices.

At its most basic, a home security system consists of a control panel(aka security console), a siren and a signal transmitter.  The control panel is the brain of your security system; it’s programmed to receive inputs from the various sensors and detectors that are connected to it (the nervous system). Most security systems come with one or more sensors.  If the system only has one sensor, it will probably be a motion detector, and might even be built into the console.  Control panels usually have a built-in keypad although some keypads are separate “remote” units; others are touch screen and/or voice activated.  The keypad is where you punch in your pass-code to activate and deactivate the alarm.  Most control panels also have a screen that displays the sensors and detectors that are active in each zone within your home. 

The siren is probably the most obvious and apparent component of the security system; in fact, it’s what we generally think of when we think of home protection - the “alarm.”  The siren can be built into the console, or the system might include stand alone sirens that can be placed at appropriate places within your property (like facing neighbors or a public street). A siren of 95 decibels or more can be heard over a significant distance. Strobe lights are also common; both they and alarms help police officers to locate the house while simultaneously scaring off intruders.

At the heart of the security system is a transmitter, which in essence is the alarm signal itself.  The transmitter receives information from the control panel, like “acoustic sensor detected a glass-break event in zone 3,” and communicates to either a central station (your monitoring service provider), you or, if you co-monitor, both. 

Types of Alarm Signals

The most common method of transmitting the alarm signal is via your home phone line.  In this case, the “transmitter” is simply an additional phone jack.  85% of home security systems in the United States are monitored this way.   When an alarm is triggered, the console takes control of the phone line, dials the monitoring station and transmits either a voice recording or predetermined data that depicts the nature of the event.

Radio transmission is the fastest communication method available, but it is not necessarily the most reliable. Security systems that use radio waves to transmit signals must be placed in certain areas of the home and tested to be sure that they can pick up available frequencies.  Many companies who sell these systems also act as the central station monitoring provider, since they specialize in receiving radio signals.  The quantity of data that can be sent via radio waves is limited as well and often times will be as simple as “burglary” vs. “fire,” without expressing any additional details. 

VoIP, which is becoming increasingly common in wireless security systems, uses your internet connection to send a digital signal to the central station.  Because central stations were traditionally set up to communicate over land lines, the signal must be converted before arriving at its final destination; thus, it is somewhat prone to error.  Because of the popularity of wireless, DIY security systems, the industry is responding by developing innovative products to satisfy each consumer’s situation, as well as many hybrid systems that take both analog and digital inputs.

Features and Accessories

In addition to the basic components above, you should know that a transformer is something that manages the power supply (“stepping it down”), a plug-in board provides additional communication or automation capabilities, including voice prompts (“voice annunciation”) and touch screens are essentially more sophisticated displays that look more like a small computer monitor.  They often come in automated home security kits, some which include software that allows you to control every aspect of your home’s security, as well as lighting, climate, audio and electrical equipment.

Many systems include CCTV or video surveillance equipment (cameras and monitors to view the footage), which can also be viewed and controlled remotely via the internet or Smartphone.  Should you think you want one, there’s a wealth of cameras to choose from (including cameras used for access control or as baby monitors) and recording devices and surveillance software to complement them.   You will have to decide whether you want to undertake the monitoring yourself or hire a central station to monitor it for you. 

Smoke detectors, as well as other environmental detectors, like those that measure carbon dioxide levels, gas and sense moisture and climate changes are usually sold separately but can often be hooked up to your main control panel.  You should definitely check to see how compatible the system is with whatever additional components or accessories you might want to add in the near future.

Some security kits contain panic buttons (aka medical alert buttons) that are built into the control panel, others put them on separate key fobs making them portable.  Ask your central station monitoring providerwhat their protocol is for monitoring panic buttons, e.g. how do they contact you when the button is pushed?  Panic buttons can ensure safety and peace of mind when they are placed by the bedside or worn around your neck or bracelet, allowing you to call for help when you perceive a threat before the security system is able to.

You will also want to consider perimeter security and access control, e.g., electric fences or gates for an added level of security.  Last, but not least, is the yard sign, fence sign (which is required on electric fences) or window stickers.  In and of itself, this can be a sufficient deterrent to sway potential criminals or vandals in another direction.  It might not be enough, however, for intruders who have no real criminal intent, like solicitors or trespassers, for which you might want additional access control.