Discharge Voltage of Arrester Connecting Lead Wires

In order to provide adequate surge protection for underground cable circuits, particularly at system voltages above 13.2 kV, the riser pole arrester discharge voltage must be held to relatively low values. The surge impedance voltage drop of lead wires connecting arresters between line and ground adds to the arrester discharge voltage, and as a consequence influences the total transient voltage that can enter the cable circuit. Because of this it becomes essential to know, quantitatively, the effect of lead wire lengths on total voltage.