| 摘要 |
PURPOSE:To elevate the reliability for the insulation of tap part of tap changing transformer and to miniaturize the apparatus by a method wherein a surge suppressing element made with a zink oxide group, which has high non-linear characteristic, is connected between tap selectors. CONSTITUTION:A divertor switch 111, having two groups of fixed contact 112, 113, a movable contact 119 and the resistor 114, 115, and two tap selectors 109, 110 connected to the contact of each group, are prepared in a tap changing transformer. A surge suppressing element 116, which is made with a zinc oxide and has the characteristic of I=(V/C)<15-50>, is connected between two tap selectors 109, 110. The similar surge suppressing elements 117, 118 are inserted between, for example, the maximum voltage tap or the middle voltage tap, to prevent discharge caused by lighting surge. By this way, the insulation of tap part is mitigated, the reliability of insulation is elevated and the apparatus can be miniaturized. |
