What is Horn Gap Arrester? – Construction, Advantages | New Topic [2024]

In this note, we are going to learn about a topic called “What is Horn Gap Arrester?“, also its construction, and advantages as well. Welcome to Poly Notes Hub, a leading website for Polytechnic Notes for Diploma Engineering Students.

Author Name: Arun Paul.

What is Horn Gap Arrester?

A Horn Gap Arrester is a type of lightning arrester that protects electrical power networks’ equipment and infrastructure against lightning strikes. It is made up of horn-shaped conductors grouped in a gap pattern. When lightning hits, the high voltage generated by the discharge causes a spark to fly across the gap between the horns, directing the surge of energy away from the protected electronics and safely dissipating it into the ground. Horn Gap Arresters are frequently employed in high voltage transmission lines and substations to reduce the effects of lightning-induced surges.

Horn Gap Arrester Image

Construction of Horn Gap Arrester

Above we are showing the Horn Gap Arrester Construction or Horn Gap Arrester Diagram –

• Horns: These are the principal conducting elements of the arrester, often constructed of copper or aluminum. They are formed like horns, hence their name, and are intended to aid in the creation of a spark gap when exposed to high voltage.
• Gap Assembly: The horns are positioned in a gap arrangement, with a specified distance between them. This gap controls the voltage at which the arrester discharges and diverts the lightning surge.
• Support Structure: A strong support system is required to hold the horns in place and keep them aligned. This construction is frequently constructed of insulating materials to prevent electrical conduction between the horns and the ground.
• Grounding System: The arrester is coupled to a grounding system, which normally consists of buried copper rods or conductors. This permits the lightning surge to safely disperse into the ground.

Horn Gap Arrester Working

The Horn Gap Arrester acts by generating a regulated spark gap. Under normal conditions, it is inactive. When there is a high-voltage surge, such as a lightning strike, the voltage across the gap increases. When it reaches the breakdown voltage, the air between the horn-shaped conductors ionizes, resulting in a conductive route and sparking. This spark directs the surge away from critical equipment via the arrester’s grounding system, fading harmlessly into the ground. After the surge incident, the spark gap extinguishes, leaving the arrester inactive until it is needed again.

When the voltage across the gap surpasses a predetermined threshold known as the breakdown voltage, the air between the horn-shaped conductors ionizes, forming a conductive route for electricity. The surge current is safely routed through the spark gap to the arrester’s grounding system. It then evaporates harmlessly into the ground, preventing damage to electrical equipment.

Advantages of Horn Gap Arrester

Below we listed some Horn Gap Arrester advantages –

1. They are capable of handling high-voltage surges
2. They have a fast response time.
3. Their construction is relatively simple, with horn-shaped conductors and a gap assembly.
4. They can be employed in a range of electrical power system applications, such as substations, distribution networks, and transmission lines.
5. Horn Gap Arresters are sturdy and dependable apparatuses.

Applications of Horn Gap Arresters

Below we listed some important Horn Gap Arresters Uses –

1. They are extensively used on high-voltage transmission lines to defend against lightning strikes and switching surges, preserving the transmission infrastructure and assuring uninterrupted power transfer.
2. Horn Gap Arresters are critical components in substations that include high-voltage equipment. They safeguard transformers, circuit breakers, switchgear, and other important assets from lightning-induced surges and transient over-voltages.
3. Industrial plants and facilities with sensitive electrical equipment employ Horn Gap Arresters to protect against voltage surges induced by lightning strikes or internal switching processes, assuring uninterrupted operation and reducing downtime due to equipment damage.