Method of triggering a high pressure sodium vapor lamp and sodium vapor lamp with improved triggering

摘要

A high vacuum sodium vapor lamp whose discharge tube is surrounded by a heating coil connected in series with a switch opening to interrupt the heating after the lapse of a heating period sufficient to allow breakdown of the tube, is also provided with overvoltage protection and especially an element located in the lamp base, for limiting the autoinductive voltage poles to a level sufficient for breakdown of the tube but insufficient to allow breakdown between the terminals of the lamp.