Example of Leakage Current Measurements
During a period of severe fog lasting 2 days, leakage current activity was monitored on insulator strings; the results for insulators on tower 59 are shown as examples (Table 4). The leakage current on nonceramic insulator NCI-2 on phase A, shown in Figure 1(a), reached peaks of 38 and 44 mA during the event. During the same event, RTVcoated superfog insulators on phase C showed higher leakage current activity, reaching levels up to 215 mA. The Veestring configuration on phase B with type NCI-2 insulators showed leakage currents of 35 and 60 mA on each leg of the Vee string, respectively. The NCI on phases A and B showed lower leakage currents compared with the RTVcoated superfog insulators on phase C on the same tower.