Sustainable mobility implications in surge protection systems

For an efficient and safe electrical vehicle charge, a specific instruction has been elaborated within the Low Voltage Regulation for the installations intended for that purpose: the ITC-BT 52. This instruction stresses the necessity to have specific material in transient and permanent surge protection. Aplicaciones Tecnológicas has tailored solutions for compliance with this standard.

Although currently less than 1% of the Spanish automotive industry is sustainable, it is estimated that in 2050 there will exist around 24 million electric cars and in ten years’ time the amount will increase to 2,4 million.

This transformation in the number of cars slows down the climate change. However, this evolution also implies the adaptation of the infrastructures that will supply this new clean technology.

Protection against overvoltages in the charge of electric vehicles

The efficient and safe charge of electric cars is a key issue in the sustainability of the new system.

This charge should be made safely, guaranteeing the vehicle and the electric system conservation, with all the protection devices needed, including those related to overvoltages.

In this regard, charging installations for electric vehicles must comply with the ITC-BT 52 to protect all the circuits against transient and permanent surge protection that can damage the vehicle during the loading process.

The regulation was published by a royal decree in the Spanish Official Bulletin (Real Decreto 1053/2014, B.O.E), in which a new Complementary Technical Instruction ITC-BT 52 was approved: «Facilities for related purpose. Infrastructure for the charging of electric vehicles».

electric vehicle

Instruction ITC-BT 52 of the Electrotechnical Low Voltage Regulation

This instruction requires to have new facilities for the supply of the charging stations as well as the modification of existing facilities that are supplied from the electric power distribution network to the following areas:

1. In new buildings or parking lots a specific electric facility must be included for the charging of electric vehicles, executed in accordance with the established in the referred ITC-BT 52:

a) in parking lots of buildings with a horizontal property regime a main conduction must be run through community zones (through tubes, channels, trays, etc.) so that it is possible to have branches connected to the charging stations located in the parking spaces, as it is described in section 3.2 of the ITC-BT 52.

b) in private parking lots in cooperatives, businesses or offices, for staff or associates, or local vehicle depots, the necessary facilities must supply one charging station for every 40 parking spaces.

c) in permanent public parking lots, the necessary facilities to supply a charging station for every 40 seats will be guaranteed.

It is considered that a building or a parking lot is newly constructed when the construction project is presented to the corresponding Public Administration for its processing on a date following the entry of the Royal Decree 1053/2014.

The buildings or parking lots prior to the publication of the royal decree had a period of three years to adapt to the new regulations.

2. In the street, the necessary facilities must be considered to provide supply to the charging stations located in the spaces for electric vehicles planned in the regional or local Sustainable Mobility Plans.

What are the possible schemes for the installation of charging points?

The installation diagrams for the charge of electric vehicles that have been foreseen in the instruction are the following:

  • Collective or branch scheme with a main counter in the origin of the installation.
  • Individual scheme with a common counter for the house and the charging station.
  • Individual scheme with a counter for each charging station.
  • Scheme with circuit or additional circuits for charging electric vehicles.

Surge protection devices for the ITC-BT 52

All circuits must be protected against temporary (permanent) and transient overvoltages.

Transient surge protection devices must be installed in the proximity of the origin of the facility, or in the main board.

In November 2017, the Technical Guide of application of the ITC-BT 52 was published, where the following is recommended:

– To install a type 1 transient surge protection upstream of the main counter or next to the main switch, located at the entrance of the centralization of counters.

– When the distance between the charging station and the transient surge protection device located upstream is greater than or equal to 10 meters, it is recommended to install an additional transient surge protection device, type 2, next to the charging station or inside it.

surge protection in your charging facility

Solution against transient and permanent overvoltages

In Aplicaciones Tecnológicas we have the right solution for an effective protection against transient and permanent surges:

To protect against type 1 transient overvoltages, Aplicaciones Tecnológicas has the ATSHOCK T 25 model (AT-8089). This element guarantees a high protection against transient overvoltages for power supply lines at the entrance of the building, including those produced by direct lightning discharges.

It is a type 1 and 2 protector according to the standard UNE-EN 61643-11 and the BT-23 guide of the REBT (Low Voltage Regulation). For equipment of categories I, II, III and IV equipment according the ITCBT-23 of the REBT.

Its main characteristics are:

  • Impulse current per pole (limp) of 25 kA and a protection level of 1,5 kV.
  • It is formed by gas discharger devices.
  • It has signs for the state of the protections.

For protection against type 2 transient overvoltages and permanent overvoltages, Aplicaciones Tecnológicas recommends the KIT ATCONTROL/R model.

It is a complete kit that includes contactor and protector against transient and permanent surges with automatic reset.

The protectors of the ATCONTROL/R series act when they detect a permanent overvoltage by triggering the associated contactor. This contactor cuts the line, protecting the equipment installed downstream. When the permanent overvoltage ceases, the protector reconnects the contactor.

The warning system of permanent surges consists of two luminous indicators, green (correct network voltage) and red (overvoltage). It has a test button to check that the installation has been carried out correctly.

ATCONTROL/R protectors also act when they detect a transient surge by diverting the current to the ground and reducing the voltage to a level which is not harmful to the connected equipment.

Suitable for equipments of category I, II, III and IV according to ITC-BT 23 of the REBT. It has a thermodynamic device for disconnection from the electrical network in case of degradation and a warning system for transient surges.

Tested and certified as a type 2 protector in official and independent laboratories according to the standard UNE-EN 64643-11 and guide BT-23 of the REBT.

Protect your electric vehicle

An electric vehicle can withstand a shock voltage of 2.500V. In case of an electrical storm, the voltage that could be transmitted to the vehicle is even 20 times higher than the voltage it can withstand, causing irreparable damages in all the system (controller, counter, communication systems, vehicle), even when the impact of the beam occurs at a certain distance.

Aplicaciones Tecnológicas puts at your disposal the necessary products to protect the charging points against transient and permanent surges, ensuring the conservation of the vehicle. In case you are interested in acquiring the protection against overvoltages, you can rely on the help of our expert staff in the matter here.