| 摘要 |
An insulation monitoring device that carries out insulation monitoring of a power system or load apparatus using, for example, an I gr method includes a table 42g in which a monitoring setting value I rref greater than a resistance component error current flowing in accordance with the sum of the electrical capacitance of a capacitor configuring a noise filter on the input side of the load apparatus and the ground insulation capacitance of the power system is set in advance in accordance with an operating schedule of the load apparatus, a monitoring setting value computing unit 42h that outputs the monitoring setting value I rref read from the table 42g in accordance with a current time according to a clock 42f, an insulation evaluation unit 42d that detects an insulation failure caused by a decrease in ground insulation resistance when a resistance component current extracted by an I gr extraction unit 42c exceeds the monitoring setting value I rref , and an alarm output unit 42e that issues an appropriate alarm in response to an output of the insulation evaluation unit 42d. |
