| 摘要 |
PURPOSE:To facilitate accurate measurement of insulation resistance under live state, by operating a current insulation resistance based on a detected zero phase voltage or current of a distribution line, ground electrostatic capacity of the distribution line and a stored initial insulation resistance. CONSTITUTION:Means 1 for detecting zero phase current or means 9 for detecting voltage of a power distribution line 5 is provided. Means 2a for storing ground electrostatic capacity and initial insulation resistance of the power distribution line 5 is also provided. Then a value detected through the zero phase current detector 1 or the zero phase voltage detector 9 and a value stored in the storing means 2a are taken into a calculating means 2 which calculates current insulation resistance of the power distribution line 5 based on the detected value and the stored value. Consequently, insulation resistance can be measured accurately under live state thus facilitating continuous monitoring of insulation resistance of the power distribution line. |
