To realize smooth control of reversible switching time, easier measurement of soft start/stop time and a method of double-interlock of a reversible non-contact contactor to be used for reversible operation of an induction motor.

A reversible non-contact contactor assures the double interlock with a trigger signal and a reversible output signal of a reversible semiconductor non-contact contactor, by detecting the soft start/stop time with the number of times of flickering such as the flickering display during the start/stop operation of the induction motor, and providing a reversible switching time adjusting function for realizing adequate setting of the reversible switching time with a CPU and a semi-fixed resistor.