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MP500/4N-8-16 Installation
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 t o 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 the EN50131-1 standard
), 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.
