According to UL 96A and LPI-175, what is the minimum ground system earth resistance value required?

The minimum ground system earth resistance value required according to UL 96A and LPI-175 is 25 ohms. This standard is critical as it ensures that lightning protection systems can effectively dissipate electrical energy into the ground.

Achieving a ground resistance of 25 ohms or lower helps ensure the safety and effectiveness of the lightning protection system. A lower resistance value allows for more efficient conduction of lightning energy, minimizing the risk of damage to the structure and its occupants. This is particularly important during a lightning event, where a well-grounded system can help prevent dangerous electrical surges.

Standards like UL 96A and LPI-175 are designed to establish robust guidelines for lightning protection, emphasizing the importance of a properly grounded system to protect against lightning strikes. In the context of lightning protection, maintaining the specified resistance is crucial for the integrity of the entire protection system.