An incident that the leakage current of metal oxide surge arrester(MOA) is higher than specified value is analyzed.Combination of infrared temperature measurement
on-line monitoring data and climate features
the cause of the above incident is due to surface pollution of MOA.The variation of the testing data caused by surface pollution is analyzed in principle.How to effectively distinguish the feature difference between the surface pollution and MOA fault is pointed out to avoid misjudging the condition of MOA.