Abstract :
The transient overvoltages caused by the effects of lightning on an overhead line distribution network can be damaging to the system equipment, costly to the supply authority carrying out the repairs and inconvenient to the customer suffering from a likely loss of power supplies. The author describes the 11 kV triggered spark gap which can be used to protect networks from lightning. It consists of a specially manufactured porcelain with a high potential, earth, and two auxilliary electrodes forming a four capacitance bridge. A single triggered spark gap on the centre conductor will cause the necessary flashover to earth