Yes, it is necessary to have a very good contact between the lower end of a lightning conductor and earth. If the connection has broken the current will pass through the neighbouring areas. So there will a flow of current around it, so it will be very dangerous

Importance of a good contact between the lower end of a lightning conductor and the Earth

Having a very good contact between the lower end of a lightning conductor and the Earth is crucial for the effective functioning of the lightning protection system. This contact ensures the safe dissipation of the electrical charge from lightning strikes, preventing damage to structures and harm to individuals. The lightning conductor acts as a pathway for the lightning bolt to follow, guiding it safely into the ground.

1. Safety
A good contact between the lightning conductor and the Earth is essential to protect buildings and people from the destructive power of lightning. When lightning strikes a structure, it can cause fires, structural damage, and even injuries or fatalities. By providing a direct path to the ground, the lightning conductor allows the electrical current to bypass the building, reducing the risk of damage and ensuring the safety of occupants.

2. Dissipation of electrical charge
When a lightning strike occurs, a large amount of electrical charge is discharged. If this charge is not effectively dissipated into the Earth, it can cause a buildup of electrical potential in the building or structure, leading to electrical surges and damage to electrical systems. By providing a low-resistance pathway to the ground, the lightning conductor allows the electrical charge to flow away from the structure, preventing potential damage.

3. Prevention of side-flashes
Side-flashes occur when the electrical charge from a lightning strike jumps from a lightning conductor to a nearby object, such as a tree or another building. These side-flashes can cause significant damage and pose a risk to individuals in the vicinity. A good contact between the lightning conductor and the Earth ensures that the electrical current is safely directed into the ground, minimizing the chances of side-flashes occurring.

4. Stability and durability
A good contact between the lower end of the lightning conductor and the Earth is crucial for the stability and durability of the lightning protection system. The conductivity of the connection ensures that the lightning conductor remains securely grounded, even in adverse weather conditions. This stability is essential to ensure the continuous and effective operation of the lightning protection system.

In conclusion, having a very good contact between the lower end of a lightning conductor and the Earth is of utmost importance for the safety, dissipation of electrical charge, prevention of side-flashes, and the stability and durability of the lightning protection system. It ensures that the electrical current from a lightning strike is safely redirected into the ground, protecting structures and individuals from the destructive power of lightning.