Series Operating Circuit of Lamps Using Silver Sulphide Resistor
Tadao Sakaguchi, Toru Noguchi, Keisuke Nishimura, Akira Kagayama, Kozo Watanabe · JOURNAL OF THE ILLUMINATING ENGINEERING INSTITUTE OF JAPAN · 1969
Silver sulphide (Ag2S) is an ionic bond crystal with phase transition temperature of 179°C. At this temperature, the resistivity of Ag2S changes discontinuously to an extent as large as 103. In β phase (179°C), the conduction of Ag2S is metallic, and its resistivity is very low.The silver sulphide resistor can be applied to a device for shorting out a faulty lamp of series operating circuit by taking advantage of the resistance change at the phase transition.In this paper, this characteristics of series circuit using this device are described.The merits of this circuit are as follows:(1) This circuit is available for discharge lamps as well as incandescent lamps.(2) The constant current regulator is not required in this circuit.(3) The silver sulphide resistor can be used for a fail shorting device repeatedly.