MP500/4N-8-16 Installation
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3.3.5 Choosing devices
Choosing the devices to be used in the alarm system means having a clear idea of what they do and how they do it. If there should be
any doubts, it could be useful to read paragraph
The devices used to create an alarm system
3.3.5.1
The detectors
Magnetic contacts are used for the doors. For security doors and other metal objects, magnetic contacts with stronger magnets are
used. Glass doors, without safety glass or bars, may resemble windows when deciding which detectors to use.
Windows are somewhat complicated to protect. Luckily, there are different types of detectors available, so it is always possible to
find a solution for any situation. If the window has a roller, a cable detector for rollers can be used. If there are shutters, a magnetic
contact can protect them. A simple window with glass, if not adequately reinforced or protected by a roller or shutter, may require
the contemporary use of a detector for breaking glass and a magnetic contact. For shop windows and skylights, breaking glass
detectors are used. The windows can then be protected with IR detectors with a barrier or curtain; in both cases the attempt to
pass through the "space" of the window is detected rather than the attempt to force the closure of the window.
For closed environments, volumetric detectors are used. The choice between IR and microwaves can be made according to
contingent factors. If the room to be protected is subject to intense and sudden changes of temperature, then using IR may result
in a greater number of false alarms. Another aspect to take into consideration when choosing among various model is the roof
area and its shape. If the environment is very big, just one volumetric detector may not be sufficient. It is better to understand that
using multiple microwave detectors in the same room may create problems of interference among them. These problems do not
exist when passive IR detectors are used or when passive IR detectors are used with a microwave detector.
Once the selection of detectors is complete, it is necessary for their number and type be coherent with the final project to be
created. It should suffice to ask a few simple questions: is there at least one sensor that protects each door or window in the
perimeter protection? If a trap protection was selected, is there at least one volumetric detector covering each important room? Are
all the mandatory passages, like stairways and corridors, covered by an adequate detector?
3.3.5.2
Sirens
Plan for at least one keypad, regardless of the arming/disarming system of the alarm system adopted.
If the complex to be protected encompasses multiple separate buildings, or if it is very extensive, or there is no façade that is more
visible than the others, then it would be better to take into consideration the installation of more than one siren.
3.3.5.3
Keypads, readers and remote controls
Plan for at least one keypad, regardless of the arming/disarming system of the alarm system adopted.
The presence of a keypad allows, for example, entry into the home or office even if the electronic key or remote control has been
lost (remember that for security reasons, it is preferable to keep the keys and electronic keys/remote controls separately), or to
provide service personnel or employees only the entry keys. Moreover, obviously, this allows the programming of the system and
the display of system messages.
It is opportune to install a keypad or reader near every point of access from outdoors. This makes use of the alarm system much
more convenient.
The same consideration should be made if, in a rather large building, there are indoor areas that are physically separated fr om
others that are identified as an alarm system partition and are always under protection. Even in this case, a keypad or a reader will
be installed nearby.
3.3.5.4
External communications
The type of communication used externally (telephone landline, mobile, SMS, etc.) may influence the certified grade of security.
When in doubt, always select the solution or device that guarantees the highest level of certification.
Due to technical or economic reasons, it is not always possible to choose the best solution. In this case, even the most restrictive
solution is preferable to a non-solution.
When making a decision, always consider not only what the control panel can communicate externally, but also what can be
communicated externally to the control panel, or in other words, how it can interact remotely with the alarm system. Succeeding in
interacting remotely with the system though the control panel may mean reducing maintenance costs and having a system that is
always efficient.
It is not always necessary to choose. If the budget and the technical characteristics allow it, various types of communication may
coexist, each of which may act as a back-up to the others. Redundancy is a plus, because the certainty that alarm notifications are
received increases.
