Lightning strikes have always been a cause of both fascination and fear due to their unpredictability and potential for damage. When lightning strikes a building or a home, it can result in a catastrophic event, damaging appliances, electrical systems, and even endangering lives. The same applies to substations, which play a crucial role in the power distribution network. To mitigate the risks associated with lightning strikes, lightning arresters have emerged as a vital protective measure. In this blog, we will explore the applications of lightning arresters in different settings - buildings, homes, and substations - and understand their importance in ensuring safety.
Buildings, whether commercial or residential, are at a constant risk of being struck by lightning due to their tall structures and exposure to the elements. A single lightning strike can cause severe damage to the structural integrity of a building and its electrical systems. To safeguard buildings against such hazards, lightning arresters are deployed.
A lightning arrester for buildings primarily consists of a metal rod or conductor that is mounted on the roof. When lightning strikes, the conductor provides a low-resistance path for the electric current to safely reach the ground, preventing it from passing through the building's electrical system. This mechanism protects the structure from damage while ensuring the safety of the occupants.
Similar to buildings, homes are equally susceptible to lightning strikes due to their exposure and proximity to lightning-prone areas. Lightning strikes can cause fires, electrical equipment failures, and even personal injuries if not adequately protected.
Lightning arresters for homes are designed to divert the high voltage of a lightning strike from entering the house. There are two types of lightning arresters commonly used for home protection: single-point and multi-point arresters.
Single-point arresters are installed either on top of the house or at the point where the electricity enters the building from the external power lines. These arresters act as conductors, redirecting the lightning energy through a grounding system and away from critical components within the home. Multi-point arresters, on the other hand, provide protection for individual appliances or electronics within the home, such as televisions, refrigerators, or computers, by redirecting the surge to a grounding system.
Substations serve as vital hubs in the power distribution network, ensuring effective transmission of electricity to homes, businesses, and industries. Due to their high energy-intensive operations, substations face significant risks from lightning strikes. Without proper protection, a lightning strike in a substation can cause transformer failures, costly downtime, and damage to critical equipment.
Lightning arresters in substations are designed to protect the valuable equipment and infrastructure. These arresters are installed at various points within the substation, including incoming power lines and outgoing feeders. Acting as surge protectors, the arresters provide a path of least resistance for lightning-induced surges, diverting the electricity directly to the ground and bypassing the sensitive components of the substation.
Lightning arresters play a crucial role in protecting buildings, homes, and substations from the devastating effects of lightning strikes. By providing a low-resistance path for the electrical charge, they effectively divert the lightning energy away from the vulnerable structures and equipment, minimizing the risk of damage and ensuring the safety of occupants.
Whether it is a commercial building, a residential home, or a critical substation, the installation of lightning arresters is a preventive measure that offers peace of mind and safeguards against the unpredictable nature of lightning strikes. It is highly recommended to consult with professionals, such as metal oxide varistor manufacturer TGE, to choose the right type and placement of lightning arresters based on specific requirements.
Lightning arresters (also known as surge arresters) come in various designs, each suited to specific voltage levels, applications, and performance requirements. The most common and widely used types today include valve-type, metal oxide (MOV-based), and gapless variants. Below, we cover these key types, their working principles, advantages, and how TGE's advanced products fit into modern protection needs.
Valve-Type Lightning Arresters
Valve-type lightning arresters were one of the earliest modern designs and remain in use in some legacy systems. They consist of a series of spark gaps combined with non-linear resistor discs made from silicon carbide (SiC).
How they work: Under normal operating voltage, the spark gaps remain open, preventing current flow. When a lightning surge or overvoltage occurs, the gaps break down (spark over), allowing the surge current to pass through the non-linear resistors. These resistors have high resistance at low voltages but drop sharply at high voltages, limiting the current and diverting the energy safely to ground.
Advantages:
Effective for high-voltage systems.
Provides good surge protection with nonlinear characteristics.
Disadvantages:
Requires spark gaps, which can lead to arcing, heat buildup, and slower response times.
Higher maintenance needs and less efficient for frequent or switching surges compared to newer types.
Valve-type arresters are less common in new installations but are still found in older substations and industrial setups.
Metal Oxide (MOV-Based) Lightning Arresters
Metal oxide lightning arresters, often referred to as MOV (Metal Oxide Varistor) arresters or zinc oxide (ZnO) arresters, represent the modern standard in surge protection. They use zinc oxide-based ceramic blocks as the core non-linear resistor material.
How they work: These arresters rely on the voltage-dependent properties of zinc oxide varistors. At normal system voltages, the MOV has extremely high resistance (acting like an insulator with minimal leakage current). During a surge, the resistance drops rapidly (within nanoseconds), clamping the voltage to a safe level and diverting the excess energy as heat without needing spark gaps.
Advantages:
Faster response time and better handling of switching surges.
Lower steady-state losses and no arcing issues.
Excellent energy absorption capacity for repeated surges.
Compact design and longer service life.
Disadvantages:
Can degrade over time with excessive surges (though high-quality units from reputable manufacturers minimize this).
These are the most commonly installed today for distribution, substation, and transmission applications due to superior performance and reliability.
Gapless Lightning Arresters (Gapless Metal Oxide Arresters)
Gapless arresters are a specific subtype of metal oxide arresters that eliminate spark gaps entirely, making them the dominant design in contemporary systems. Also known as gapless ZnO or MOV surge arresters, they use a solid stack of metal oxide varistor discs.
How they work: Without gaps, the arrester continuously monitors the system voltage. The ZnO material remains highly resistive under normal conditions but becomes conductive during overvoltages, instantly clamping the surge and shunting current to ground. This gapless construction provides seamless protection with no sparkover delay.
Advantages:
Superior protective margin and lower discharge voltages.
Reduced power losses and no risk of gap-related failures.
Ideal for high-reliability applications like substations, switchyards, and renewable energy systems.
Better performance in polluted environments and under temporary overvoltages (TOV).
Disadvantages:
Slightly higher initial cost in some cases, but offset by longevity and low maintenance.
Gapless designs are now the industry preference per standards like IEEE C62.11 and IEC, offering the best combination of protection, durability, and efficiency.
Why Choose TGE's Lightning Arresters?
At TGE (Xi'an Tiangong Electric Co., Ltd.), we specialize in high-performance metal oxide varistor (MOV) blocks that form the heart of modern gapless lightning arresters. Our products include advanced ZnO-based MOVs for distribution, substation, line, and GIS applications, meeting or exceeding IEEE, IEC, and GB standards. Whether for buildings, homes, industrial facilities, or critical substations, TGE's arresters deliver reliable surge protection with excellent energy handling, low leakage current, and long-term stability.
Explore our full range of MOV-based surge arresters and cores on our products page or contact us for custom solutions tailored to your voltage class and environment.
This variety of types ensures the right lightning arrester can be selected for any application, from residential homes to high-voltage substations, minimizing risks from unpredictable strikes.
Lightning arresters are widely used to protect various structures and electrical systems from lightning strikes and transient voltage surges. Their main applications include safeguarding buildings (commercial and industrial), residential homes, electrical substations and switchyards, power distribution lines, solar PV systems, telecommunications equipment, and sensitive industrial machinery. By providing a low-resistance path to ground, they divert harmful surge energy away from protected equipment, preventing fires, equipment damage, power outages, and safety hazards.
Lightning arrester installation for buildings usually involves mounting the arrester (often a Franklin rod or air terminal) at the highest point of the structure (roof peak, chimney, or antenna) to act as the primary strike receptor. A down conductor (heavy copper or aluminum cable) routes the lightning current safely down the exterior of the building to a dedicated grounding electrode system (ground rods or ring earth). For surge protection inside, additional surge protective devices (SPDs) are installed at the main electrical panel. Professional installation is strongly recommended, especially for multi-story or industrial buildings, to ensure compliance with standards like NFPA 780 or IEC 62305 and to achieve effective equipotential bonding.
In a switchyard (the outdoor high-voltage section of a substation), lightning arresters operate by clamping excessive voltages caused by direct or indirect lightning strikes. When the system voltage exceeds the arrester’s rated protective level, the metal oxide varistor (MOV) material inside rapidly decreases in resistance, allowing the surge current to flow through the arrester to the grounding grid. This shunts the surge energy away from sensitive components like circuit breakers, current transformers, busbars, and feeders, keeping the voltage across equipment below its withstand level. After the surge passes, the arrester quickly returns to a high-resistance state with very low leakage current under normal operation.
PREV
NEXT
English 
