| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a device for protecting load circuits, capable of immediately interrupting only a load circuit if dead short-circuiting occurs in the load circuit, in order to protect the load circuits. <P>SOLUTION: The protection device includes an E1 detection circuit 13 and an E2 detection circuit 12. The E1 detection circuit 13 detects a back-EMF (electromotive force) E1 produced in a common wiring for connecting a plurality of load circuits and a power source VB. The E2 detection circuit 12 detects a back-EMF E2 produced in a part of load connection wiring for connecting each load circuit. Then, if it is detected in the E1 detection circuit 13 that the back-EMF E1 generated in the common wiring exceeds a predetermined threshold and if it is detected in the E2 detection circuit 12 that the back-EMF E2 having an identical direction with the E1 occurs at the load connection wiring, a relevant load circuit is interrupted. Thereby, when a short-circuiting accident occurs, this load circuit can be immediately interrupted, while other load circuits can be operated continuously. <P>COPYRIGHT: (C)2010,JPO&INPIT |
