Leakage resistance data acquisition system for porcelain insulators along the coast

The leakage resistance of transmission line insulators suspended along the coast decreases with the accumulation of sea-salt blown from the sea, particularly when the relative humidity is high and the shed surface is slightly wet with rain or wet snow. In order to measure, automatically, by a leakage resistance data acquisition system including a personal computer, the real time leakage resistance properties of a string of 3 standard suspension porcelain insulator units and a porcelain long rod insulator subjected to +1500V DC voltage depending on the coast weather conditions, a field test site was prepared in Rumoi, a heavily sea-salt affected area on the coast of the Sea of Japan, in December 1990. This paper presents data collected in 1992. The leakage resistance was affected by the wind direction depending on whether or not the wind bore sea-salt particles, by relative humidity, and by precipitation