| 摘要 |
PURPOSE:To detect a trouble before it developes into a major one by a method wherein a photo detecting part is provided on the auxiliary contact point of a pair of a movable contact point circuit part constituting a tap changer and in the vicinity of a current limiting resistor, photo fibers facing to said auxiliary contact point and photo detecting part are connected to the photo-electricity converter provided outside a case, and the arc of the auxiliary contact point and the light of a red-heated resistor are detected. CONSTITUTION:Taps T1 and T2 are led out from the tap winding WT provided on the low tension or high tension winding of a transformer, they are connected respectively to the movable contact point circuits 6a and 6b which are housed in the case of a changer through the intermediary of movable contact points 1a and 1b. At this point, the circuits 6a and 6b have the entirely same structure, and pertaining to the circuit 6a only, it is composed of a resistance contact point vacuum valve Wa whereon the circuit 6a is series-connected, an auxiliary contact point Ka, a main contact point vacuum valve Ha, and a series-connected current limiting resistor Ra. According to this constitution, a photo fiber F1 constituting a photo detector 8 is faced to the auxiliary contact point ka and a resistor Rb, and the extended part F2 of the photo fiber F1 is connected to a photo-electricity converting part 11 through the intermediary of the infrared ray filter 13 of the connection part 19 provided on a cover 9. |
