Preventing Leakages at Insulators
Leakages at insulators, cracking of insulators and flashover across insulators frequent cause outages and give output in loss of revenue. Pollution is a major cause for this damage. Because of pollution a deposit is created on the insulator surface. The surface layer might absorb moisture and become semi-conducting causing leakage currents to flow. The surface gets heated and leads to an avalanche causing a flashover and cracking of insulator.
Use of appropriate material for insulators (like porcelain, glass and etc. depending on the nature of pollution in the local area) and designed protected creepage path helps in decreasing insulator failure. Preventive actions are regular inspection and hot line washing, the latter being particularly appropriate for coastal areas and areas along with chemical industries.