Alarm systems: How do house alarm systems work?

Welcome to our blog on how alarm systems work, whether you call them intruder alarms, burglar alarms or house alarms they all do the same job and that is to protect your property. For the purpose of this blog, I will try to keep it as non-technical and easy to follow as possible.

An intruder alarm system is made up of 4 basic components, the master control panel, the keypad, sensors, and a warning signal such as a bell box siren or strobe lights. You can read more about alarm systems below:

Domestic Intruder alarms here

Commercial Intruder alarms here

 Let us look at each component in a little more depth.

The Alarm keypad

This is used to arm and disarm the alarm and is usually positioned near an exit/ entry door for ease of use. A personal user code is needed to set the alarm, the code should not be disclosed to anyone that does not live at your address for maximum security. Key fobs and proximity tags can also be purchased for most modern-day alarm systems, these allow the user to either arm/disarm the alarm by either showing a proximity tag to the keypad Key fobs are a little bit like car keys, they allow you to arm and disarm the alarm before you enter the property say as you are driving on to your driveway.

PIR Sensors

Passive infra-red sensors or more commonly known PIR’s can detect motion by picking up infrared radiation. All living things emit infrared radiation, when an alarm is armed and an animal or human move into its sight it detects the infrared radiation that is emitted and sends an electronic signal to the master control panel to activate a warning signal.

 PIR sensors mainly come with pet motion sensors, pet immunity settings slightly differ from a standard PIR, they allow small pets up to approximately 35 kg to be able to wander around without setting the alarm off. 

Door contacts

Door contacts are installed on doors and windows, they consist of a sensor and magnet that is installed so that when the door/window is closed they sit next to each other and when the door is opened, they separate.  When the alarm is set, and the doors and windows are shut if the magnet and the sensor come apart in the case of the door/window opening it will send a signal to the master control panel to activate the warning signal from the bell box.

Glass break detectors/shock detectors

Glass break detectors sense the high pitch sound waves of glass shattering due to the small inbuild microphones. The microphones listen for the high pitch frequency sound of breaking glass, when it hears the sound, it will trigger the alarm to activate.

Shock detectors

Shock detectors detect any type of vibration on a window from banging the window to the window being broken. When a shockwave is detected, it will send a message to activate the alarm.

The alarm systems Bell box

This is the part that scares the burglars away. The bell box houses the warning siren and or strobe lights. This is where the noise is produced to make you and everyone else aware that the alarm has activated.

At CJB Installation services our best sellers by far are the wireless alarm systems.  They are neat and tidy and come without any unsightly wires which can be a pain especially if you have just decorated!  It comes with a year’s free subscription to the Pyronix cloud, this allows you to arm/disarm, turn individual sensors off and be alerted if your alarm is activated from anywhere in the world from your smart phone. Giving you the ultimate peace of mind knowing that your home or business is safe and secure.

Pyronix wireless alarm systems

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