| 摘要 |
PROBLEM TO BE SOLVED: To prevent the problem of tripping errors caused by the output drop of a photovoltaic element, when an inspection-purpose interlocking circuit for controlling a power FET to normally an 'on' sate is provided for the inspection of the tripping circuit in a breaker. SOLUTION: An interlocking circuit 15 includes an insulated transformer 15A at the input side and turns on or off a power FED 15D with the 'on/off' of an AC current inputted into the transformer. The AC current is obtained from the output of windings provided on an insulated transformer in a control power supply 16 for relays 1, 2. This also includes the case where it is obtained from the chopper output of a chopper circuit. At inspections, the output of the relay 2 makes the AC input of the transformer zero via a photocoupler 18. |
