The purpose of lightning protection grounding is to:
- Disperse the lightning current effectively into a large surface area of soil.
- Handle current pulses with fast rise time without excessive rise of the potential near the ground electrode connection point.
To design a lighting protection system that disperses the lightning current into the ground and minimizes potentially dangerous overvoltages, the shape and dimensions of the grounding system are important. A low grounding resistance is recommended.
| When planning and designing a lightning protection system, the shape and dimensions of the grounding system are critical in determining how it works in practice. |
Low impedance grounding, which means small inductance and preferably high capacitance, is essential for the proper operation of transient suppressors and lightning protection systems. Vaisala recommends using several parallel routes that disperse the current to a large surface area of soil.
| A lightning protection and grounding system requires three or more ground rods in the ground electrode. Using fewer rods does not provide sufficient protection and may cause dangerous step voltages. |