Principles and Functions of a Surge Protector Against Lightning

A surge protector against lightning is an electrical device designed to protect electronic devices, communication equipment, and other sensitive electrical equipment from lightning strikes and electromagnetic surges. It is typically installed at the input end of an electrical system, serving as the first line of defense.

The working principle of a surge protector against lightning is based on its internal variable resistor elements. When the voltage is within the normal range, these elements have high resistance, preventing current from passing through. However, when there is a sudden voltage spike, such as from a lightning strike or electromagnetic surge, the resistance of these elements drastically decreases, forming a low-resistance path that directs the overvoltage to the ground. In this way, the surge protector against lightning absorbs and dissipates the excess energy from the high voltage, protecting the equipment within the system.

While both surge protectors against lightning and lightning arresters are used for lightning protection, there are some key differences between them.

• Different working principles: Surge protectors against lightning primarily limit overvoltage through changes in resistance, directing the excess voltage to the ground; whereas lightning arresters, also known as lightning rods, distort the ground electric field as a lightning cloud discharge approaches the ground. At the tip of the lightning rod, a space with a concentrated local electric field is formed, influencing the direction of the lightning leader discharge, guiding the lightning to discharge towards the lightning rod. The current is then directed into the ground through a grounding wire and grounding device, thereby protecting the object from lightning strikes.

• Different applicable scopes: Surge protectors against lightning are more suitable for electronic devices and sensitive electrical equipment, whereas lightning arresters are used to protect buildings, tall trees, etc., from lightning strikes. A striker is installed at the top of the object to be protected and connected to a ground drainage network with compliant wires, usually used to protect buildings, antenna towers, and other large structures.

• Different response speeds: Surge protectors against lightning have a relatively fast response speed, capable of responding to voltage changes within milliseconds; lightning arresters have a relatively slower response speed, requiring some time to release the overvoltage.

In modern industries, the stable operation of electrical systems is crucial to the production process. As an effective protective device, the surge protector against lightning provides reliable protection for electrical systems through its unique working principles and mechanisms. Compared to lightning arresters, surge protectors against lightning perform better in protecting sensitive equipment, contributing significantly to the reliability and stability of industrial electrical systems. By thoroughly understanding surge protector against lightning, we can better comprehend the applications and value in the industrial field.