JP2560736B

PURPOSE:To increase the electric life of a current controller and to reduce the heat generation at the time of energizing by providing a first terminal, a superconducting element connected to the terminal for limiting a current, a semiconductor element connected in series with the superconducting element for breaking a current limited by the superconducting element, and a second terminal connected to the semiconductor element. CONSTITUTION:A load current flows sequentially through a lead connected to a first terminal 23A, the terminal 23A, a superconducting element 30, a semiconductor element 21, a second terminal 23B and a lead connected to the terminal 23B. When a short-circuiting current flows, it exceeds a critical current of the element 30, the superconducting state of the element 30 is broken to become a high resistance state. Thus, the short-circuiting current is limited. Then, a detector is operated, the element 21 is interrupted by a control signal to the terminal 22 to interrupt the short-circuiting current. On the other hand, the element 30 is not operated to limit the current of small value for breaking, but interrupted by the element 21.