Wire breaking arc testing circuit for physiotherapeutic apparatus

PROBLEM TO BE SOLVED: To provide a disconnection spark detecting circuit for a physical treatment device which can securely detect a disconnection spark caused by a defective contact of a treatment guide. SOLUTION: This disconnection spark detecting circuit 5 is inserted into the output line 2 of a physical treatment device. The disconnection spark detecting circuit 5 consists of a detection transformer 6 and a rectification/ integration circuit 7 which rectifies and integrates a disconnection spark voltage detected by the transformer 6 to make detection outputs. Two equally-divided first coils 6p1 and 6p2 are wound around the output line 2 so that the coils 6p1 and 6p2 generate magnetic flux in reverse directions to each other, and a disconnection spark in the output line 2 is detected by the detection transformer 6 which takes out signals from a secondary coil 6s. In this way, a disconnection in the output line can be securely detected.