What protective devices does an EV charging point need in Spain?

EV charger protection requirements under ITC-BT-52

The protection an EV charging point needs is set by section 6 of ITC-BT-52, the part of Spain’s low voltage regulations dedicated to electric vehicle charging. It is stricter than for an ordinary socket because the car can spend hours charging at 32 A.

1. A dedicated circuit

The charger has its own circuit, with no other loads except the unit’s auxiliaries. In homes it is circuit C13.

2. A curve C MCB

It protects the line against overloads and short circuits. It is all-pole and sized to the cable: for example, 40 A with 10 mm² cable or 32 A with 6 mm² for a 7.4 kW charger, depending on the length and the installation method.

3. A 30 mA RCD, at least type A

Each connection point is protected by its own 30 mA RCD (diferencial), at least class A. The regulation does not literally require DC detection, but the technical guide, standard UNE-EN IEC 62955 and the manufacturers recommend it: a fault in the car’s on-board charger can inject direct current that blinds a type A RCD. The solution is:

• a type B RCD, or
• a type A plus a 6 mA RDC-DD, which almost every quality wallbox has built in.

4. Surge protection

It is compulsory against temporary and transient overvoltages. The protector goes in the main fuse board and, if the charger is far away, another one is fitted next to it, coordinated with the first. In Seville, Spain, with the summer storms and the value of the car plugged in, it is essential.

5. Earthing and TN-S system

The circuit has a protective conductor, and the only earthing system allowed is TN-S, with neutral and earth kept separate all the way to the charging point.

Where they are fitted

In a detached house, usually in the home’s fuse board. In a communal garage a small board is fitted next to the space with the MCB, the RCD and the surge protector, and the charger is fixed to the wall or a pillar at about 0.8 to 1.2 metres from the floor.

When to call an electrician

Call if you are installing a charger, or if yours lacks this protection or trips often. In Seville, Spain, we install it through home EV charger installation for houses and fit surge protection.