The monitoring system classifies leakage current peaks in five ranges, as shown in Table 1, and the microprocessor monitors all leakage current pulses in each half cycle (8.33 milliseconds) for all three phases and provides a data summary every 9 hours. Thedata contain the maximum leakage current pulses, have the ac-cumulated peaks classified into each of the five ranges, and haveautonomy for 6 months, after which the data need to be down-loaded and the system reset to begin a new monitoring period.