PURPOSE: To automatically count the number of times of spark generation so as to save labor by providing a spark detector for detecting a spark of an electric discharge element without a contact so as to output the result as an electric signal, and a counter.

CONSTITUTION: A condenser microphone unit 12 serving as a spark detector is housed inside an electric discharge element protecting casing 9, for acoustically detecting a spark sound at the time of generation of a spark of an electric discharge element 8, converting the sound into an electric pulse signal, and sending the signal to a digital counter unit 13. In the unit 13, a wave form shaping circuit 16 is adapted to receive the electric pulse signal and shape it into a rectangular pulse, to thus send the pulse to a monostable multivibrator circuit 17. The circuit 17 inputs the pulse as a pure pulse excluding a noise pulse into an up/down counter 18. The counter 18 counts the input pulse to send the count value to a display 23, where the count value is visibly displayed by a light emitting diode. Consequently, it is possible to save labor because the unit 13 can automatically count the pulse signal, thereby enhancing workability.