| 摘要 |
PROBLEM TO BE SOLVED: To provide a means which can determine whether the state of the normal leak current of an electric path is in a range of being able to guarantee the detection accuracy of a requested grounding current for a resistor and also is practical and economical, in an apparatus such as a molded case circuit breaker, an earth leakage breaker, a relay, or a measuring instrument, which includes a means for detecting the ground leakage current of an electric path and detecting the magnitude of the leakage current due to grounding through a resistor, based on the phase difference between the magnitude and the voltage of the electric path. SOLUTION: The apparatus, which detects the ground leakage current of the electric path and detects the grounding current for a resistor, based on the magnitude and the shift of the phase from the voltage of the electric path, includes a means which issues an alarm when the phase shift between the ground leak current and the voltage of the electric path is beyond a specified range. COPYRIGHT: (C)2009,JPO&INPIT
|
