In the operation of transformer bushing dirty harmAddtime：2015/3/27 

transformer bushing surface dirt, dirt due to absorption of water, resulting in reduced insulation. This will not only easily cause the surface discharge of porcelain bushing, but also may make the leakage current increase, causing the casing fever.  porcelain bushing surface dirty, the flashover voltage is reduced, when line overvoltage phenomenon, it will cause porcelain bushing flashover discharge, cause damage to the surface of ceramic, the insulation breakdown of an important factor.