All modern houses with electrical installation they have one and, nevertheless, it is probably the most unknown technological element and to which we pay the least attention in our house.
Its technical name is General Command and Protection Panel, but familiarly we know it as “electrical box” or “light box”, and its main function is to control the electrical installation and protect both electrical equipment, appliances and household devices as well as its inhabitants from possible discharges.
Basically it’s kind of junction box full of wires generally located behind or near the entrance door to the house and that shows a series of switches or levers that most mortals do not dare to touch in case we spoil something. What does it consist of and what are its main functions?
House electrical panel: parts and functions
Each house is a world and the electrical panels that we can find today are the most varied, many of them with a few decades behind them and fewer installed components, others of recent batch and full of switches and sections.
In general, the usual thing is that we find the following elements, although not all of them may be present in our installation: a PCI (Power Control Switch), a ID (differential switch), multiple PIAs (small circuit breakers), a IGA (Automatic General Switch) and a PCS (Surge protector). Let’s see what each of them consists of.
PCI: The Power Control Switch is a mandatory element in homes according to current regulations (article 10 of RD 1454/2005) and its mission is to cut off power supply in the house when from within we demand more power than that officially contracted with our electric company or in cases of overload or short circuit, to avoid damage to the installation.
Normally the ICP is usually separated from the rest of the switches, with its own cover and sealed so that we cannot manipulate it, although in the most modern installations it was integrated into the panel itself and now with the massive implementation of smart meters, this function is integrated directly inside them.
IGA: The Automatic General Switch is an element incorporated in modern electrical panels and its mission is cut off electricity to the entire house in case of a short circuit or exceeding an excess of power because we have many devices on.
It also takes care that we do not exceed the maximum power that our installation is capable of withstanding even if we had contracted a higher power with the electricity company. For example, we could contract 10 kW with the distributor but our wiring could not support more than 5 or 6 kW. The IGA ensures that we do not exceed those 6 kW in daily use.
ID: The Differential Switch is easy to identify since it usually carries a rotary lever or a test button which should be done at least once a year to check that everything works as it should. This element protects the installation against current leaks, avoiding electrocutions.
If at any time the ID jumps, it is because a current leakage to ground has occurred due to an anomaly in the installation or due to a faulty appliance.
PCS: Surge Protector protects electrical appliances preventing them from being damaged by surges or voltage spikes caused by any reason, such as lightning during a storm, and sends the current to the ground to avoid damage.
PIAs: The Small Automatic Switches protect each of the interior circuits in the different sections of the house. They separately control the arrival of electricity to the different circuits of the house and there is usually one for lighting, another for high power plugs, several for low power plugs, etc. with different values of supported power that vary between the 10A, 16A, 20A and 25A.
They are always together, in the form of a set of small magneto-thermal levers that are activated if they detect an excess of electrical consumption in a part of the house. In this way only that area is left without electricity, but not the rest of the house.