Surge protection devices (SPDs) are used to protect electrical and electronic equipment from voltage surges or transient overvoltages. A voltage surge is a temporary increase in voltage that lasts for a short duration and can occur due to various reasons, such as lightning strikes, switching of electrical equipment, or utility grid disturbances.

The main purpose of surge protection devices is to divert excess voltage away from sensitive equipment, preventing damage and ensuring the reliable operation of electrical and electronic devices. Here are the key reasons why surge protection devices are used:

1. Protection against Lightning Strikes: Lightning strikes can cause extremely high voltage surges that can damage or destroy connected equipment. Surge protection devices provide a low-impedance path for the surge current to flow to the ground, diverting it away from the equipment and minimizing the risk of damage.

2. Safeguarding Electronics: Many modern electronic devices, such as computers, televisions, routers, and smartphones, are susceptible to damage from voltage surges. Surge protection devices installed at the power supply entry point or on individual devices help protect sensitive electronics from sudden voltage spikes.

3. Extending Equipment Lifespan: Voltage surges can cause gradual wear and tear on electronic components, reducing the lifespan of equipment. Surge protection devices help in maintaining a stable voltage supply, thereby extending the operational life of electrical and electronic devices.

4. Preventing Data Loss: For electronic devices that store important data, such as computers and servers, voltage surges can lead to data corruption or loss. Surge protection devices mitigate this risk by diverting surges away from the equipment.

5. Ensuring Uninterrupted Operations: In critical applications or industrial settings, unexpected downtime due to equipment damage can be costly. Surge protection devices help ensure uninterrupted operations by safeguarding equipment from voltage surges.

6. Meeting Regulatory Requirements: Some industries or locations may have specific safety regulations that mandate the use of surge protection devices to protect equipment and personnel.

It is important to note that surge protection devices do not eliminate voltage surges entirely, especially in the case of direct lightning strikes. However, they significantly reduce the impact of surges and provide a valuable layer of protection for sensitive equipment. Surge protection devices can be installed at various points in the electrical system, including at the service entrance, distribution panels, and individual devices, to provide comprehensive protection against voltage surges.