In this paper, we develop a explosion-proof LED lighting (Ex circuit) circuit of Explosion-proofLED Signal Lamp (Ex LSL) to utilize the core module of the explosion-proof Local Control System (ExLCS) for offshore plant applications. And then analyzed its electrical, optical and thermal characteristics. Ex circuit was applied input voltage from AC/DC(12～254) V. In this experiments, stable light-oncharacteristics were confirmed by eyes for the every input voltages with min. 78,462 and max. 517,975cd/m2 of luminance. also Output current and output luminance was made proportional. Because themeasured maximum surface temperature of Ex circuit was 54.23℃ at AC 48 V, Ex circuit was rated withT6 of temperature class. Finally, Ex circuit was shown stable light on characteristics under the?50℃ and60℃ during 12 hours of test period.
