DIMMER

PROBLEM TO BE SOLVED: To provide a dimmer which restrains a fault from occurring when an inductive load is connected by mistake.SOLUTION: A dimmer D comprises: a switching circuit 1 including a pair of switching elements Q1 and Q2 which are connected in series facing oppositely each other within a current loop in which a current from a commercial AC power supply returns via an illuminator to the commercial AC power supply; a charge/discharge circuit 2 which repeats charging to each gate of the pair of switching elements and discharging therefrom with the timing corresponding to an operation alternately for the pair of switching elements; a surge voltage detection circuit 3 which detects a surge voltage developing between opposite ends of the switching circuit 1; and a surge voltage absorption circuit 4, connected in parallel with the switching circuit 1, which absorbs a surge voltage developing between the opposite ends of the switching circuit.