Discharge and emission spectra on the surface of polymer insulator materials in salt fog aging test

A deterioration diagnostic method using salt fog aging test particularly on silicone rubber that possesses hydrophobic recovery properties has now been developed. Two kinds of discharges occurring in the salt fog aging test adversely affected the silicone rubber material. Using a spectroscope and still camera, the discharge characteristics of spectral distribution and optical observation were observed. High-speed camera images of the corona and dry band arc discharges in the, salt-fog aging test were studied. The results, confirmed the corona discharge emission spectra is mainly ultravioliet and that of dry band arc discharge includes the yellow-red range of the electromagnetic spectrum.