1.1 This standard applies to the measurement of partial discharges during tests with alternating voltage, but general terms, definitions and require050928087050ments are usually also applicable for measurement of partial discharges during tests with direct voltage. Some special characteristics of partial discharge measurements under direct voltage are given in a separate clause and necessary references are made throughout the text. The standard is intended principally as a general guide for drafting specifications for specific apparatus.
1.2 Even though they involve only small amouts of energy, partial discharges may lead to progressive deterioration of the dielectric properties of insulating materials; the definition and evaluation of such deterioration, however, are beyond the scope of this standard.
1.3 The standard deals mainly with electrical measurements of partial discharges, but some reference is also made to non-electrical methods.