w40 series mcb has small size,light weight,novel structure and excellent performance.they are mounted in the illuminationdistribution board and used in gusethoused,block of flats,high buildings,squares,airports,railway stations,plants and enterprises etc,in ac circuits 240v (single-pole),up to 415v(3-pole) 50hz for protection of overload short circuit and for circuit changober in lighting system.breakoing capacity is 3ka.its indicator can be used circuti indication in illumination and industry system.