| 摘要 |
PROBLEM TO BE SOLVED: To provide a ground fault interrupter comprising a test function capable of confirming whether a ground fault detection function is normal, without interrupting an AC electric circuit.SOLUTION: The ground fault interrupter comprises: a ground fault discrimination part 5 which is connected to a secondary coil 3a of a zero-phase current transformer 3 inserted into an AC electric circuit 1, detects a ground fault current flowing in the AC electric circuit 1 and outputs a ground fault detection signal; a tripping device 8 for opening an opening/closing contact 2 inserted into the AC electric circuit 1 in accordance with output of the ground fault detection signal; a test circuit that makes a test current flow to a test coil 12 of the zero-phase current transformer 3; a self-check test pulse generation circuit 15 supplying a test pulse signal for self-check to the test circuit; and a test pulse discrimination part 17. The ground fault interrupter also comprises a self-check abnormality display device 22 in which, when the test pulse signal for self-check is outputted but is not detected in the test pulse discrimination part 17, abnormality is determined and a test result is displayed without operating the tripping mechanism 8. |
