Electricity

Electrical magnitudes

We need to know the fundamental magnitudes to properly understand an electrical circuit. Without going into all of them, we will expose the main aspects that are the three most known to the general public: tension, intensity and resistance.

The voltage, E(volt), also called "potential difference" and more familiarly "voltage" is related to the working capacity that an electrical charge can perform. Using a hydraulic simile, it would be the water pressure, due to a pump or a level difference. The unit is called Volt (V) and, to have some references, it can be said that a battery or battery has a voltage between 1 volt and a few tens of volts, the home power grid operates at 230/400 V and a transmission airline operates between 11,000 and 400,000 volts.

Intensity I(A) is the amount of "electrical charge" electricity that circulates through a conductor per unit of time. In hydraulics would be the flow, the m3 per second passing through a pipe. The unit is called Amperio (A) and, by way of example, we can say that a domestic electric stove consumes about 4 to 8 amps. It is worth noting the expression that circulates because regarding the intensity it is often to make the mistake of talking about "a plug, a switch, etc. 10 A." Well, the actual intensity in home applications can be between 0 A - if nothing is connected - up to thousands of amps if the connected device is defective or short-circuited. The figure indicated on the device itself is the maximum intensity applicable, permanently, for the heating purposes of the same, not the actual intensity at any time.

Resistance R(Ω) is the measure of the degree of difficulty offered by a body (water, air, earth, wood, iron, gold, copper, etc.) for electric current to circulate through it. In hydraulics it would be equivalent to the difficulty of passing water through a pipe according to its diameter and length. The unit is the Ohmio (A) which is defined as the resistance that allows the passage of 1 A under a potential difference of 1 V.

The three magnitudes are not independent of each other. Resistance is considered not a fundamental magnitude, but is calculated from tension and intensity using ohm's well-known Law:

R (Ω)= E(volt)/I(A)

Just as a faucet allows to vary the flow of water passing through a pipe, it is also possible that the electrical resistance varies from one human body to another, and depends on the contact surfaces, the moisture state of the skin and other circumstances. This should be taken into account when considering the possible consequences of electric shock.

Differential Circuit Breaker

Therefore, we must first know what a differential circuit breaker (or switch) is and what thermomagnetic circuit breakers are. And what a function they play.

The differential circuit breaker is an automatic protection system that is installed on the electrical panel of any electrical installation and has the function of protecting people's lives. It works by cutting off the power supply if it detects that there is a difference in the intensity of the electric current (measured in Amperios) entering the house and the one that leaves. The current intensity is constant. For this reason, if there is a difference – because the intensity coming out of the house is less than the one that has entered – it is because an intensity leak is occurring in the electrical circuit that can be fatal to a human being. The differential circuit breaker grounds that difference in intensity and automatically cuts off the electricity supply to the electrical circuit. Its role is to protect people.

As we said above, the intensity of the electric current is the amount of electrical charge that passes through a circuit. Well, 15 mA (milliampere) is enough to kill a person.

Differential circuit breakers are classified as follows:

• Depending on its phases (single-phase or three-phase),
• Depending on the potential difference to which they will be subjected (230 V or 400 V),
• Depending on the maximum intensity that can pass through them and their sensitivity, being the most common of 30 milliamps and 300 milliamps and
• Depending on the time required for your reaction, it should not be less than 30 milliseconds.

Thermomagnetic Circuit Breaker

Thermomagnetic circuit breakers, also essential in an electrical installation, cut off the electrical power supply either because a particular circuit is overloaded or because a short-circuit occurs in the installation. The thermomagnetic circuit breaker is opened and its function is to protect the electrical installation of the house and household appliances. In this way we avoid, for example, that fires occur in the houses.

We install a differential circuit breaker and several independent magnetothermal circuit breakers for each service (lighting, general plugs, oven, washing machine, fridge, etc.), according to regulations. We also install a new corrugated tube (independent for each service, be it this lighting, general plugs, oven, washing machine, etc.) throughout the house, embedded by the walls and hidden in the false ceiling. Then we insert by the corrugated tube the new cable, of different sections - depending on its destination (lighting, oven, fridge, etc.)

We never use the old electric corrugated tube or the old wiring.

We also installed a telecommunications box: it consists of installing an internet plug in each room and having them centralized in a single box. In this same frame the antenna conductions are centralized. With this we achieve a higher quality in the signal and that the possible operator changes be easier and do not involve loose or overlapping cables by the skirting board, etc.

On the other hand, if you need to perform the intelligent automation of your home or business (home automation), we have specialists who can meet your needs.

Likewise, if you want to install an alarm and video surveillance system (with motion sensor, infrared, etc.) connected to central alarms or with operation from your own phone, we can help you and propose the solution that best suits your needs.