APPARATUS FOR MEASURING LEAKING CURRENT FROM INSULATOR

摘要

PURPOSE:To make it possible to improve measuring accuracy, to simplify an apparatus, to make the apparatus compact and to reduce cost by converting a picked up current from a current collecting means through a resistor into a voltage, and detecting the voltage with a voltage sensor. CONSTITUTION:A current flowing through the surface of an the insulator of an insulator string device 20 between a power transmission and distribution line 28 and its supporting structure 21 is detected with this apparatus. A current collected with a current collecting means 2 which is provided at the outer sur face of a metal can part 20a of the insulator is converted into a voltage through a resistor 4 in a lead wire 3. The voltage is detected with a voltage sensor 5 of a current detecting means 6. Thus the converted voltage is detected with the sensor 5 without the use of a CT (current transformer) and a power ampli fier. The effects of an external magnetic field, noises and a electric field are not received. The difference in impedance directly between the device 20 and the structure 21 and the current path through the lead wire 3 can be made large with an insulating body 7 that is provided additionally. Even the minute current can be measured accurately.