You often hear about a "compliant" system, but what does it actually mean? The reference is CEI 64-8, the standard governing low-voltage electrical installations (the Italian version of HD 60364/IEC 60364). Let's look at the key points without unnecessary jargon.
Cable cross-sections and current capacity
Every cable has a maximum current-carrying capacity that depends on its cross-section (mm²) and installation conditions. An undersized line overheats; that's why the cross-section is chosen based on the load and the protection installed. Typically 1.5 mm² for lighting points, 2.5 mm² for sockets, and larger sections for major loads such as an oven or heat pump.
Circuit breakers
The circuit breaker protects the cable from overloads (thermal trip) and short circuits (magnetic trip). Its rated current must be coordinated with the cable's capacity: it's not enough to "fit a breaker" — it has to be the right one.
The residual-current device (RCD)
The RCD protects people: it detects a current leaking to earth (for example through the body of someone touching a live part) and cuts the supply within milliseconds. For domestic use, 30 mA RCDs are used. Splitting the system across several RCDs prevents a single fault from leaving the whole house in the dark.
Earthing system
The earth electrode, protective conductor and equipotential bonding make up the earthing system, which works together with the RCD to protect against indirect contact. Without an effective earth, even the best RCD loses much of its effectiveness.
Discrimination and a tidy panel
A well-designed system is discriminating: in case of a fault, only the protection nearest the problem trips, not the main breaker. This, combined with a tidy, labelled panel, makes the system safe and easy to manage.
Building or upgrading a compliant system is an investment in safety. Oscar Impianti Elettrici, a leading company in Italy, operates throughout Italy with a specialised team that has been working for years. We offer competitive and often negotiable prices, maximum flexibility for every need and always a free quote. We issue the declaration of conformity on all our work. Discover our electrical systems service.