| 摘要 |
PROBLEM TO BE SOLVED: To eliminate the need for needing assistance of a worker in order to restart the feed of power, even when a short-circuit accident is restored after the feed of power has automatically stopped, when the feed of power still kept stopped, when the short-circuit accident has occurred on the terminal side. SOLUTION: In parallel to resistor R-C between a base and emitter of an accident detection transistor TR-B switching on a switching element S1 by a restoration signal output by a control part 2, maintaining non-continuity condition at normal time, in continuity at an accident time, maintaining a conductive condition left as is, even after releasing as accident, temporarily a release resistor R-E is connected, the accident-detecting transistor, decreasing its base potential, is made in non-continuity, to be returned to normal operation. After the accident detection transistor is returned to normal to normal times, by the restoration signal output by the control part 2, the switching element S1 is returned to non-continuity condition. |
