The construction of an electrical system is an important aspect in any construction project or building renovation because it must be safe, in accordance with the law, better if it lasts over time and, if possible, would have been useful in a short time.
For all this to be possible, it is essential to follow some simple, but necessary, rules of execution. Specifically, the essential steps will be:
- planning: study of the building and the positioning of the elements of the system;
- wall tracing: selection of the walls inside which the pipes will pass;
- creation of space for cables: creation of special compartments in which the tubes containing the cables will be placed;
- choice of the safest and most suitable wires and related materials;
- verification of compliance (carried out by experts) of the plant.
Electrical system: design
An electrical system plays an important role in any building and must be designed and built in an effective and functional manner, so it is best to be meticulous in every design phase.
In the first place it is necessary to examine a plan of the building in order to study the areas in which the appliances or machinery will be installed or any other instrumentation that requires electricity. Based on the size of the rooms it will be possible to choose the power and type of the system between 3kW and 6kW. Subsequently it will be necessary to study the position where to place the panel (which includes the general and the two lifesavers) from which it will be possible to manage the entire system. Finally, during the planning phase it will be necessary to decide which position the outlets will have, the earthing system leading to the switchboard and the different switches. All these preliminary decisions will be essential during the construction of the plant as they will allow you to work in a precise, fast and highly secure manner.
Tracing of walls and creation of space for cables
After the design phase, the so-called tracing of the walls and ceilings will follow in order to identify the most correct passage for the junction boxes, the lighting points and the device-holder boxes.
After this first phase, you can start the actual work that will go to create a special space in the wall that allows you to correctly pass the pipes that will lead the cables (and therefore the current) to the points defined above. Afterwards, the conduits must be inserted in the appropriate slots and connected with the elements of the system to then be covered and therefore included in the wall. The cables will be inserted with a special device.
The best wires to make a safe and durable system
To realize a domestic system in a fast but safe way, it is generally advisable to choose 2.5 sq. Mm wires with the exception of the areas destined to specific loads that require a higher power such as, for example, appliances where the wires to be used are those of 4 sq mm.
This last type of wire, moreover, according to the regulations governing domestic electrical systems, must also be used for protection conductors.
The earth plant
Safety is essential when building a domestic electrical system. It is necessary that the current has a way of “venting” and it can therefore be dispersed in the ground to avoid that the presence of anomalies or failures is dangerous for the plant itself and neighboring appurtenances. The earth installation, therefore, is made up of earth rods, earth collectors, wells, protective conductors, and the circuit breaker, also known as differential.
The circuit breaker, better known as a differential switch, is nothing but a device that has the purpose of interrupting the conduction of electricity in the circuits and systems. The system detects the difference of incoming and outgoing currents in the event of leakage.
The installation of this equipment is necessary so that, in the event of a fault, leakage and electrocution do not put people’s lives at risk. However, this does not provide any protection in the event of a short circuit or overload.
What are the rules for a plant according to law
Given the essential role of the electrical system, this must possess certain requisites established by law.
Specifically, Ministerial Decree 37/2008 determines all the rules for which it is possible to recognize, for any system, the so-called certificate of conformity which establishes its proper functioning, safety and allows it to fall within the required compliance parameters by the CEI for Italy e.g. (Italian Electrotechnical Committee). Only qualified personnel registered in the company register can decide whether or not the plant has the characteristics required by law. This last step also takes place after an accurate test, necessary to verify its safety and correct operation.
From this it can be seen how each step for the realization of an electrical system needs particular attention and is aimed at obtaining this certificate of conformity, from the detailed design, to the personnel in charge of the realization, as well as to the choice of the correct materials that facilitate the installation as pre-wired conduits as required.