According to the Crime in England and Wales Report published in 2007, homes and offices equipped with an alarm system are three times less likely to experience a break in. Indeed, we all know that there is a need to install an alarm system so that we will be alerted when there is an intruder or when an emergency is about to happen, but we may not be so sure what actually make up of a good alarm system.
Typically, three things are inseparable from an alarm system; first and foremost, a detector. A reliable detector should react to incidences such as movement, jolt, tremor, change in temperature and water level etc. Some detectors come with passive infrared sensors (PIRs) which can detect if a person is moving via infrared heat sensing. Others may make use of Dual Technology – that is to combine sensing technologies via infrared and microwave in reducing the likelihood of a false alarm. Detectors also come in the forms of door or window contacts, so that alarm will sound when the door is open or when window is broken.
Secondly, an alarm system should also come with the control panel. This is also known as the “brain” of the whole alarm system as it is where all the detectors or sensors are connected to. A control panel will analyse all the signals transmitted from the detectors. A control panel usually comes with a keypad, which serve the purpose of controlling it. When an alarm goes off, the keypads within the control panel will identify what is the possible trigger and the information can be communicated either by LED indicators (for LED keypads) or texts (for LCD keypads).
The third component to an alarm system will be the siren. Sometimes, different tones are set to reflect if the alarm had been triggered internally or externally. External trigger is more vital in this case as it serve an additional purpose of deterrent or to seek the attention of outsiders for extra help. There are also optional component such as the communication device in which pre-recorded speech can be sound out when the alarm is triggered. These messages can be sent out by the control panel to users’ phones or contacts, which comes in handy especially when the user is not around.
Once we have the basic knowledge for making up a reliable alarm system, the next thing one should consider will be the locations to which the system is to be placed.