Luminescence in tracking test of polymer insulating materials

This paper presents a study on effects of flammation retardant in polycarbonate (PC) on the luminescence phenomena during the tracking tests. A photo multiplier tube was employed to measure the light intensity, which is found to be well in accordance with the development of tracking failure. The results obtained reveals that light is easily emitted when the phase angle of applied voltage is around 90° and 270°. Weak initial light indicates the coming scintillation discharge; the continuously enhanced light is associated the scintillation discharge and the arc discharge. Each light pulse is composed of a main pulse and scores of small pulses. With the increasing flame retardant in PC, the luminescence intensity significantly decreases. The detecting technique of luminescence is sensitive to measure the light information from faint discharge pulses during the tracking tests.