| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a circuit breaker for detecting occurrence of connection failure in its early stage without making a substantial design change and by minimizing increase of the number of components. <P>SOLUTION: A connection failure detecting circuit to detect connection failure of a terminal is connected to a power supply side terminal 2, the terminal seat 10 of the power supply side terminal 2 is fixed to the housing 1 of the circuit breaker by a fixing screw 14 together with a circuit board 8 forming the connection failure detecting circuit. The connection failure detecting circuit determines the connection failure by detecting a potential difference generated between a wire 4 and the terminal seat 10, performs electrical connection with the terminal seat 10 through the fixing screw 14, performs electrical connection with the wire 4 by bringing one end of a contact metal fitting 19 the other end of which is connected to the circuit board 8 into contact with a nut 12, and determines the connection failure if a detected potential reaches a prescribed value. <P>COPYRIGHT: (C)2010,JPO&INPIT |
