An AC high-voltage device comprising: an AC transforming unit configured to transform supplied power to an AC high-voltage; an over-current detecting unit configured to detect an over-current in the AC high-voltage; a main controlling unit configured to output a target value of the AC high-voltage, and that has an abnormality determining unit configured to determine an abnormality; and a voltage controlling unit (212, 215, 216) that includes a constant-voltage controlling unit (212, 215, 216) configured to control the AC transforming unit so that the AC transforming unit outputs the AC high-voltage targeted on the target value; and an turn-off unit (212, 215) configured to turn off the AC transforming unit so that the AC transforming unit stops outputting the AC high voltage, wherein when the over-current detecting unit does not detect the over-current, the constant-voltage controlling unit (212, 215, 216) controls the AC transforming unit so that the AC transforming unit outputs the AC high-voltage targeted on the target value, for a period of time during which the over-current detecting unit detects the over-current, the turn-off unit (212, 215) turns off the AC transforming unit, and after the period, the constant-voltage controlling unit (212, 215, 216) re-starts to control the AC transforming unit, characterized in that: the voltage controlling unit (212, 215, 216) is further configured to output an operation-signal to the main controlling unit during the period of time during which the over-current detecting unit detects the over-current; the abnormality determining unit is configured to determine that the abnormality has occurred when the operation-signal continues for a predetermined period; wherein the main controlling unit does not output the target value and the voltage controlling unit (212, 215, 216) turns off the operation-signal when the abnormality determining unit determines that the abnormality has occurred; and the AC high-voltage device further comprises a resetting unit configured to reset the main controlling unit to initial state when the abnormality determining unit determines a single occurrence of abnormality in a predetermined period. an AC transforming unit configured to transform supplied power to an AC high-voltage; an over-current detecting unit configured to detect an over-current in the AC high-voltage; a main controlling unit configured to output a target value of the AC high-voltage, and that has an abnormality determining unit configured to determine an abnormality; and a voltage controlling unit (212, 215, 216) that includes a constant-voltage controlling unit (212, 215, 216) configured to control the AC transforming unit so that the AC transforming unit outputs the AC high-voltage targeted on the target value; and an turn-off unit (212, 215) configured to turn off the AC transforming unit so that the AC transforming unit stops outputting the AC high voltage, wherein when the over-current detecting unit does not detect the over-current, the constant-voltage controlling unit (212, 215, 216) controls the AC transforming unit so that the AC transforming unit outputs the AC high-voltage targeted on the target value, for a period of time during which the over-current detecting unit detects the over-current, the turn-off unit (212, 215) turns off the AC transforming unit, and after the period, the constant-voltage controlling unit (212, 215, 216) re-starts to control the AC transforming unit, characterized in that: the voltage controlling unit (212, 215, 216) is further configured to output an operation-signal to the main controlling unit during the period of time during which the over-current detecting unit detects the over-current; the abnormality determining unit is configured to determine that the abnormality has occurred when the operation-signal continues for a predetermined period; wherein the main controlling unit does not output the target value and the voltage controlling unit (212, 215, 216) turns off the operation-signal when the abnormality determining unit determines that the abnormality has occurred; and the AC high-voltage device further comprises the voltage controlling unit (212, 215, 216) is further configured to output an operation-signal to the main controlling unit during the period of time during which the over-current detecting unit detects the over-current; the abnormality determining unit is configured to determine that the abnormality has occurred when the operation-signal continues for a predetermined period; wherein the main controlling unit does not output the target value and the voltage controlling unit (212, 215, 216) turns off the operation-signal when the abnormality determining unit determines that the abnormality has occurred; and the AC high-voltage device further comprises a resetting unit configured to reset the main controlling unit to initial state when the abnormality determining unit determines a single occurrence of abnormality in a predetermined period.