Thunderstorms: Consequences for your home and how to protect yourself

In the domestic environment, there is more and more electrical and electronic equipment with very complex and necessary functions that facilitate daily life. But if these computers are not adequately protected, they are subject to damage during a thunderstorm. In the residential sector, it is essential to have adequate protection to avoid damages that, most of the time, entail high costs.

When we talk about home protection, we have to keep in mind that, even if you have a good external lightning protection system (lightning rods etc), you can still suffer the negative effects caused by overvoltages. An overvoltage refers to an increase in the voltage in the electrical network that can cause damage to the electrical, telephone, television or grounding lines.

This occurs because in most homes, the lines that enter can be damaged due to the electromagnetic effects of lightning, both from an impact captured by the external system, as well as a distant lightning strike or even the impact of a lightning strike on the line itself. In the case of buildings without an external protection system, the risk is greater, since the lightning current will find its way to ground through the most direct routes, and may even pass through the equipment.

What are the devices affected by electrical damage?

The damage they can suffer is more evident in electronic equipment, such as computers, televisions and their peripherals, often interconnected, multiplying the chances that an overvoltage can affect them. But they are not the only ones.

The effects caused by transient overvoltages of atmospheric origin translate into economic losses, ranging from the momentary interruption of work or the deterioration of components, to the total destruction of electrical or electronic equipment such as refrigerators, garage doors, alarms, heating systems, TVs, computers, printers…

The main elements or devices that can be affected by electrical storms in your home are: telephone, television, refrigerator, ceramic hob, oven, dishwasher, washing machine, microwave, air conditioning, heater, fireplaces, ceilings, water services, gas pipes and nearby trees.

The devices, which can be affected by electrical damage, represent 92% of the existing electrical devices in a home. For this reason, lightning and surge protection is essential for household equipment.

Lightning damage: losses and insured costs

Lightning impacts in residential areas are a problem directly related to home insurance. Currently the number of lightning strikes is increasing and along with the damage they cause concerns are raised, not only for insurance companies but also for residents who see that their homes are ever more vulnerable with the increased amount of electrical equipment.

The data provided by the Insurance Information Institute (Triple-I) in the United States tells us that the average cost per claim increased 2.6% from 2018 to 2019.

Domestic Surges claimsFor this reason, having basic equipment to protect you from lightning and the surges they cause is essential, as some of the damage that thunderstorms cause can lead to fires, structural damage and the aforementioned surges. These damages, in turn, bring about a series of costs for the insurers to consider: intervention of the fire services due to debris and rehabilitation; breakage of household appliances and even accommodation that should be given to the insured and their family in the event of temporary uninhabitability.

Having an external lightning protection system, together with an adequate earth connection and surge protection devices not only protects the house and the devices that are in it, but, as in some European countries, you can reduce your insurance premium by ensuring that your storm damage costs will be lower.

In any case, the importance of the damage that lightning can cause in your home goes beyond the simple economic costs, since they can entail sentimental or even personal losses.

Solutions to prevent overvoltages at home

The need for protection is increasing, as technology evolves and makes electronic components smaller and more sensitive to electromagnetic disturbances.

Currently most electrical systems are equipped with safety measures to prevent short circuits and electric shocks to people, electrical and electronic devices.

However, these general protection elements are not able to avoid the consequences of transient overvoltages, since their activation is much slower than the voltage spike that occurs. They are also not prepared to protect against so-called permanent overvoltages, increases in line voltage of less intensity but of longer duration, also causing significant damage to the equipment. The protection devices against transient and permanent overvoltages are complementary to the general protections (thermomagnetic, differential).

Aplicaciones Tecnológicas has a wide range of solutions to prevent damage from both temporary and permanent overvoltages, and effectively protect the most frequently used domestic electrical and electronic equipment.

Power Supply Protection

KIT ATCONTROL/B PT. Complete kit that includes a combined protector against permanent and transient surges, emission coil and general automatic switch.

Permanent surges

IT ATCONTROL-B PTProtectors from the KIT ATCONTROL/B series act when they detect a permanent overvoltage by firing the emission coil connected to it (S1, S2). This emission coil triggers the trip of the General Automatic Switch, protecting the equipment installed downstream.

The temporary overvoltage warning system is formed by 2 light indicators: green (correct power supply) and red (overvoltage). It is provided with a test button in order to check that the installation has been correctly carried out.

Transient surges

KIT ATCONTROL/B protectors also actuate when detecting a transient overvoltage, driving the current to the earth and reducing the voltage to a level that does not damage the connected equipment.

Tested and certified as a Type 2 protector in official and independent laboratories following the UNE EN 61643-11 standard and the REBT GUIDE-BT-23. Suitable for Category I, II, III and IV equipment according to REBT ITC-BT-23.

It has a thermodynamic device for disconnection from the network in case of degradation and transient overvoltages warning system that lights up if the protector withstood an overvoltage over its capacity. Indicates that the device should be replaced.

Protection for Telephone Lines

AT-9101 ATFONO Protector for telephone lines. Efficient protection for analogical and ADSL in modules with coordinated medium and fine protection for a single pair of wires.

  • ATFONOProtection for telephone lines as well as the digital and analogical equipment connected to these lines.
  • Discharge takes place in an internal encapsulated element, with no external flash.
  • Module includes both common and differential modes of protection
  • Low residual voltage
  • Very fast response
  • Connection of conductors via mechanical pressure points, which provides better lightning current withstand capacity than usual telephone connectors.

ATFONO SPD has been tested in official, independent laboratories, obtaining their characteristics according to relevant standards.

Surge protectors for TV lines

ATFREQ SERIE. Wide range of protectors for different frequencies and connectors. Due to their placement, aerials are one of the most exposed elements to lightning discharges. Even when an external lightning protection system exists, the discharge secondary effects can affect the TV or RF signals.

ATFREQ Surge Protective Devices protect the signal cable deriving the induced and conducted surges to ground, thus avoiding damages to the communication and TV equipment as well as connected devices (video, DVD; decoders, home cinema, etc.).

  • ATFREQOptimum coupling with imperceptible losses
  • Small attenuation in the signal even for very high frequencies
  • Short response time
  • No deflagration
  • Compact size
  • Specific connectors for each application


Surge protective devices for data lines

ATLANAT-2107 ATLAN. Single protector for local networks. ATLAN SPDs are specifically designed to avoid failures in data transfer between equipment within the same network. They protect the input of the electronic circuits of the network cards against harms due to transient currents.

ATLAN is a protector with RJ45 input and output connectors, with a withstanding current of up to 2kA for each pair of lines. It is designed to individually protect each and every piece of equipment connected to the computer network.

Installing a lightning rod at home increases your safety

And finally, the installation of an external lightning protection system is recommended, since it avoids direct impacts on the structure by diverting the passage of lightning current in a controlled manner to the grounding installation.

Aplicaciones Tecnológicas recommends the installation of an Early Streamer Emission Air Terminal DAT CONTROLER® REMOTE, which is characterized by responding to the approach of the lightning bolt, anticipating its capture before any other element within its protection zone, leading it to ground safely. Furthermore, it incorporates a remote status testing device to guarantee its correct operation at all times.


If you need expert advice on surge protection contact us. For our surge protector selection guide, you can download it here.