| 摘要 |
<p>PURPOSE:To enable a stable closing composition test with high reliability, by perfectly separating a switch to be tested from a current source circuit and separately applying voltage to both terminals of the switch to be tested to lower the voltage applied to a current closing device. CONSTITUTION:A main transformer 2 has a tap 2a for taking out a large current and one terminal 4a of a switch 4 to be tested is connected to said tap 2a to receive the application of high voltage. A current closing device 5a is inserted between one terminal 4a of the switch 4 and the tap 2a and bridged by a current transformer 6 when a current is flowed to the switch 4. An earth closing device 11 bridged simultaneously with the closing device 5 by the current transformer 6 is inserted between the other terminal 4b of the switch 4 and the earth and a sub-transformer 9 is provided in parallel to the closing device 11. By this method, because the switch 4 is perfectly separated from the power source of a current source circuit when high voltage is applied by separately applying voltage to both terminals of the switch 4, high voltage can be applied to both terminals of the switch 4 while the voltage for operating each closing device is kept low.</p> |
