| 摘要 |
PROBLEM TO BE SOLVED: To accurately determine short-circuit of an electrical installation even when a phase advance capacitor installation for improving power factor is installed in the electrical installation. SOLUTION: This device applies an alternating voltage of variable frequency generated in an alternating voltage generator 14 from a detection probe 13 to two phases of the electrical installation and detects current flowing into the electrical installation by applying of the alternating voltage of variable frequency. An impedance display part 16 calculates and displays impedance of the electrical installation from the current flowing into the electrical installation and the applied alternating voltage. A checker changes the frequency of the alternating current generated in the alternating voltage generator 14 so that the impedance of the electrical installation should be maximum with a frequency variable device 15, and determines whether or not the electrical installation might be short-circuited based on the maximum value of the impedance. COPYRIGHT: (C)2008,JPO&INPIT
|
