Electrical discharge machine and failure determining method

A failure determining method of an electrical discharge machine comprising a machining power supply having a plurality of different circuit states, and configured to be capable of being set to one circuit state of the plurality of circuit states by switching at least one of electrical connection and electrical setting, and the machine configured to perform electrical discharge machining by applying a voltage to an inter-electrode gap formed between an electrode and a target workpiece and to cause a current to flow, the failure determining method comprising:

• a state determining step of, when each of the plurality of circuit states is set as the circuit state of the machining power supply, determining whether or not the set circuit state is normal;
• a failure portion specifying step of specifying a failure portion of the machining power supply based on a determination result with respect to each of the plurality of circuit states provided in the state determining step;
• a reporting step of reporting the failure portion specified in the failure portion specifying step to an operator;
• and
• a setting switching step of setting each of the plurality of circuit states as the circuit state of the machining power supply sequentially by switching at least one of the electrical connection and the electrical setting,
• wherein, in the state determining step, when the circuit state of the machining power supply is switched, whether or not the switched circuit state is normal is determined.