urmet domus 1067/024, Руководство по установке

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DS1067-063D
35
LBT20064
Let's example the typical alarm system to understand how they are powered. Particular or complex systems can have
different configurations.
Wired systems
The power supply and the batter are contained in the control panel, from which multipolar cables branch out to connect
the various devices. These cables include two conductors dedicated to the transport or power to the devices. The mains
power supply provides the primary source of electricity to the control panel, which in turn powers the various devices.
When the power network is interrupted, the battery takes over to power all the system devices. Once the electrical
current is restored, the battery is disabled and the power supply recharges it to its maximum capacity.
One particular function is the main siren. This is in fact equipped with a rechargeable battery or batteries that enable it to
general acoustic and light alarms, even if electrical current is missing from the control panel. Devices of this type are
called "self-powered". If the battery installed is rechargeable, then the power supply that arrives from the control panel is
also used to maintain the charge or recharge it as needed.
Radio system
In this case all the devices are equipped with non-rechargeable batteries. The radio control panel, instead, can be
completely powered by batteries or have both a power supply and a battery, like a standard wired control panel. The last
configuration is obligatory when the control panel has a communicator inside for the mobile telephone network. This
device actually consumes a lot of electricity and would soon consume the control panel battery, making the system
unusable.
3.3 HOW TO DESIGN AN ALARM SYSTEM
A good design facilitates the work involved in the installation and, more importantly, ensures that the intrusion alarm
system fulfils its scope of punctually notifying the presence of any threat to the people or property that is must protect.
Step by step, beginning with defining the security needs, below is an explanation of what to do to protect property and
persons, how to choose the devices to reach the objectives, how to install them effectively in the environment and,
finally, which checks to carry out if radio frequency extensions are used (radio detectors and other devices connected
with the mobile phone network).
3.3.1 Analysis of the site and needs
The first thing to do is to have a clear idea of what must be protected and the needs of the people who must use the
system. Being able to have a floor plan or map of the places to be protected helps during the successive planning and
installation phases.
The first question to ask is: “Who and what must be protected and what grade of security must be guaranteed?” Indeed,
it may be that not all the property must be protected in the same way. For example, a tool shed or a garage may not
need to be protected in the same way. It may be that something is not protected because it is not worthwhile, and priority
will be given to using resources where there is something truly important to be protected.
It is just as important to understand what current needs are and how they may evolve in the future. The choices for a
system are in fact made according to the configuration of the site and places and the user needs. Making the wrong
decision because there is not a clear idea of the final result may mean redoing everything, which in turn leads to higher
costs.
3.3.2 Certification requirements
The certification of a system according to intrusion alarm system laws and standards is very important. Firstly, because
certification ensures that the alarm system provides the desired protection, secondly because it could be a prerequisite
for eligibility for discounts on insurance policies or the possibility of being connected with Law Enforcement bodies,
security agencies, and alarm reception centres.
Once the necessary and desired grade of security has been established (see paragraph Conformity with EN50131-1 ), it
is necessary to verify that the system you wish to create corresponds to what the standards recommend. There are two
figures that ensure this:

the manufacturer , who builds and certifies his products;

the installer , who constructs the system state-of-the art, following indications provided by the standards.
IMPORTANT! It is very important to understand that the level of security guaranteed by a system is determined
by both the products used and how the installation was carried out. In other words, if devices certified for high
grade of security are used, but if the installation is lacking or even not in correspondence with the standards, the
system will be without certification or with a very low grade of certification. Likewise, carrying out a perfect
installation from a technical and standards point of view does not guarantee certification if the system uses
uncertified devices.
IMPORTANT! The certification of an alarm system does not correspond to the certification of an electrical system.
An alarm system could be perfectly in conformity with electrical system standards, but not respect those of an
intrusion alarm system. The certification issued by the installer must explicitly declare that all the devices installed
are certified for a grade of security equal or greater to the one indicated for the system and that the installation
respects the standards. It is also preferable that the specific standards be cited clearly in the document.