Abstract
This paper investigates transient measurements in a scale-down vertical conductor above a conductor plate. A number of experimental studies of a lightning surge in transmission towers have been carried out. However, the influence of measuring wires layout on the measured result has not been well investigated. This paper discusses the effect of a current lead wire and the layout. When a coaxial cable being used as the current lead wire, the measured voltage becomes lower than that for a covered (or bare) conductor being used. For example, the tower top voltage is reduced by 20% in the coaxial cable case. The induced current from the conductor plate representing the earth to the current lead wire also affects the measured result. The sheath current in the coaxial cable case also influences measured results significantly. Thus, it is recommended to use a covered conductor as current lead wire in a scale model experiment above a conductor plate.
