Patent ID: 7574152

Claim:
An AC high-voltage device comprising: an AC-transforming unit that transforms supplied power to an AC high-voltage; an over-current detecting unit that detects an over-current in the AC high-voltage; a constant voltage controlling unit that outputs a target value of the AC high-voltage; a turn-off/on unit that, when the over-current detecting unit detects the over-current, makes the constant voltage controlling unit stop AC-transforming by the AC-transforming unit for a first predetermined period, and when the first predetermined period passes, makes the constant voltage controlling unit re-start the AC-transforming by the AC-transforming unit; an intermittent signal outputting unit that outputs, when the turn-off/on unit repeats stopping and re-starting of the AC-transforming as an intermittent control, an intermittent control signal indicating a continuing of the intermittent control; a main controlling unit that determines whether the intermittent control signal continues to be output during a second predetermined period which is longer than the first predetermined period, and when it has been determined that the intermittent control signal continues for the second predetermined period, stops the AC-transforming unit due to an abnormality.