Experimental analysis of earth wires for induced lightning surges

Experimental studies were made on induced lightning surges on multiconductor systems. The results obtained support the theory that an induced voltage on a conductor of a multiconductor system is the same as that on a single-conductor line occupying the same position. The effectiveness of earth wires against induced voltages were checked and a general formula for many earth wires with many earth connections was established. Basically, the effectiveness of earth wires can be attributed to the current flowing through the earth wires, which reduces the induced voltage on a phase conductor due to coupling.