A lightning arrester is a device that is used to protect electrical equipment and facilities against lightning strikes and power surges. When lightning strikes a structure or a power line, it can generate a high voltage surge that can damage the equipment and even cause fires. A lightning arrester is designed to divert this high voltage surge away from the equipment and into the ground, thus protecting it from damage.
Working Principle of Lightning Arrester
The working principle of a lightning arrester is based on the concept of electrical breakdown. A lightning arrester is made up of a metal oxide varistor (MOV) block that is connected between the phase conductor and the ground. The MOV block’s resistance is very high under normal operating conditions, but as the voltage surges during a lightning strike, it becomes a conductor and diverts the surge to the ground.
Different Types of Lightning Arresters
1. Station Class Arrester: This type of arrester is used on transmission and distribution lines to protect high-voltage equipment against power surges and lightning strikes. They are designed to handle high current and voltage surges.
2. Intermediate Class Arrester: This type of arrester is used on distribution lines to protect low-voltage equipment against power surges and lightning strikes. They are designed to handle lower current and voltage surges.
3. Distribution Class Arrester: This type of arrester is used on transformers and other low-voltage equipment to protect against power surges and lightning strikes. They are designed to handle low current and voltage surges.
Location of Lightning Arresters
Lightning arresters are usually installed at the point where the electrical lines enter the structure or facility. For transmission lines, the lightning arresters are usually located at the power substation. For distribution lines, the lightning arresters are usually installed near the transformers or other equipment that needs protection.
Differences between Lightning Arresters
The main difference between the different types of lightning arresters is their current and voltage rating. Station class arresters are designed to handle high current and voltage surges, while distribution class arresters are designed to handle lower current and voltage surges.
Advantages of Lightning Arresters
1. Protect Electrical Equipment: Lightning arresters protect electrical equipment against power surges and lightning strikes, preventing damage and potential fires.
2. Cost-effective: Installing a lightning arrester is a cost-effective solution compared to repairing or replacing damaged equipment due to lightning strikes.
3. Easy to Install: Lightning arresters are easy to install and require minimal maintenance.
Disadvantages of Lightning Arresters
1. Limited Protection: Lightning arresters provide protection against power surges and lightning strikes, but they cannot protect against all types of electrical disturbances.
2. Grounding Issues: If the grounding is not proper, then the lightning arrester may not be able to divert the surge to the ground, resulting in damage to the equipment.
Conclusion
In conclusion, lightning arresters are an essential component of any electrical system operating in areas prone to lightning strikes and power surges. They protect electrical equipment from damage and potential fires and are easy to install and maintain. Ensure to use the appropriate lightning arrester according to the current and voltage rating of the equipment. The results will be fewer failures and longer equipment life.