MP500/4N-8-16 Installation
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Wired technology is particularly indicated:
in new constructions or in those to be remodelled, where it is possible to have a conduit system where wires can be passed;
in those situations where radio shields or significant sources of electromagnetic disturbances are found;
Radio technology is particularly indicated:
in inhabited buildings or where it is not possible to intervene on the wall structure;
where wiring can be particularly costly and difficult;
for temporary intrusion alarm systems;
As can be deduced from this information, both technologies are in some way complementary. Where one is weaker, the other is
stronger. For this reason, there are market solutions that allow the creation of hybrid systems, where both technologies can be used to
benefit from the best of both.
2.1.2.1
Radio apparatus
There are two types of radio apparatus used in the alarm systems: those that allow the system to connect to the external environment,
like the radio modules for the cell phone network, and those that allow wireless communications within the system, mainly between
radio devices and the control panel.
It is important to verify that the radio devices of the alarm system use the specific frequencies established by legislation and that they
are capable of using more than one radio channel.
Some may ask: can these radio devices create disturbances for other equipment present? Are all these electromagnetic waves
harmful?
The answer to the first question is very simple: the conformity with laws practically excludes this type of problem.
The same is true for the second question, but in this case it is better to analyse the topic in more detail. Above all, the radio devices
transmit with extremely low power; secondly they mainly work as receivers and transmit only when necessary and for durations of just
a few seconds. In other words: they almost never transmit and so do not emit electromagnetic waves; when they must do so it i s only
for very brief moments and very low power.
2.1.2.2
The bus
A particular type of connection is the bus, which can be either wired or radio. It is essentially a channel of communication th at transfers
data and information among the various devices of the system, guaranteeing their interaction.
A wired bus may physically resemble an ordinary "electrical connection, but one that transmits enormous quantities of data and
information in digital format, following a specific protocol. One bus can connect several devices together, thereby simplifying a wiring
project.
2.2
COMMUNICATING WITH THE EXTERNAL ENVIRONMENT
If suitable designed, the alarm system may interact with the external environment not only locally, but also remotely. Alarms , signalling,
images, and sounds can be replicated event at a distance of thousands of kilometres. Likewise, although far away, enabled users can
send commands to the system, activate its functions, and even manage it.
What it is possible to receive or do depends on the functions offered by the system, on the means of communication used, and on the
remote device used.
The main means of communication used by the intrusion alarm systems are:
Telephone network
Mobile network (GSM).
Internet
LAN
The receivers of the signals may be, in addition to the owner and other contacts he selects, Law Enforcement bodies, Security
agencies, and alarm reception centres.
ATTENTION!
The possibility of sending alarm signals to State or local law enforcement must be requested explicitly and
authorised by them. More details can be obtained at the local or regional police station. Security services and alarm reception
centres offer the service for payment.
The company that installed the system may be among those enabled to remotely operate it. In this way it is possible to conduc t
diagnostics and eventual maintenance more easily, because the technician need not go their directly, but will be able to work remotely
with a PC.
In the best systems, security against unauthorised access is guaranteed by the fact that each remote connection session by the
installer must be previously authorised by the owner.
Maintenance interventions of this type may be charged for separately.
The presence and type of the means of communication used by the intrusion alarm system can influence its certification.
