It is not unusual for amateur to confuse between a closed circuit television (CCTV) or an alarm system, regarding the two as inseparable or misunderstood one for the other. Indeed, a well-structured surveillance system is best to incorporate the duo, nevertheless, users still have the freedom to dominate one over the other, depending on their needs and the context in which the systems will be employed.
Let’s just focus on alarm system for now, to avoid confusion.
A typical alarm system should accommodate a detector, a control panel, and a siren. A detector, as the name proposes, reacts to all forms of movements, tremor, changes in temperature or water level, and jolt etc. Some detectors can be found in contact with doors or windows, that set off the alarm when they are open, broken, or being forced free. It is also common to embed passive infrared sensors (PIRs) in some of these detectors, as an additional caution to check if someone or something is moving with the use of infrared heat sensing. Others include Dual Technology, which make use of both the infrared and microwave on sensing technologies, to minimise the likelihood of a false alarm.
The control panel is regarded as the “brain” of the entire alarm system because it is the base for all detectors and sensors. Pairing with a controlling keypad, the main role of a control panel is to decode all signals transpired from detectors. In the incident when the alarm is triggered, the keypads on the control panel will hence identify the possible provoking source(s) via the use of LED indicators (for LED keypads) or texts (LCD keypads).
Last but not least, the siren. Often, users set different tones for different triggers so that they can immediately recognised if the incident took place internally (something happened within the surveillance premise) or externally (something outside the surveillance premise had triggered the alarm). Most of the time, more attention is given to the external trigger as it serves as a way of deterrence and also to seek the attention of outsiders for additional help. In commercial setting, communication devices with pre-recorded speech(es) may come together with the siren so that the public can be informed and to remain calm when an alarm goes off.
Other miscellaneous components such as the backup unit, may sometimes be found in the alarm system too, especially in areas where blackout or electricity shortage are more likely to happen. In such circumstance or when someone is trying to cut the system’s wires so as to gain access without triggering the alarm, the backup unit will make sure the control panel is working normally, so that users or relevant authorities can still be informed instantly.
With the advance in technology, putting up an alarm system can be as fancy as going onto a fashion runway. However, always keep in mind your surveillance needs and communicate them to an expert, so that the most suitable system can be installed.
Go on for CCTV’s anatomy in the next article.