ABNORMALITY DETECTOR OF ELEVATOR CAR ILLUMINATING DEVICE

摘要

PURPOSE:To provide an abnormality detector of an elevator car illuminating device by which service life of a glow lamp may be predicted and non-lighting condition of a fluorescent lamp may not be generated. CONSTITUTION:Current waveform is detected from a fluorescent lamp drive circuit by a clamp type current detector. Waveform is formed by an envelope circuit 6 and an A/D converter 7 and accumulated in a memory 8, and variation time of current is measured by a computing circuit 9 based on the waveform. Whether the glow discharge time which is stored in advance is good or not is judged by a comparison circuit 11 and a judging device.