| 摘要 |
<p>PURPOSE:To prevent a fault current induced by other phase and line from continuously flowing and effectively protect power transmission line by detecting any fault current cutoff in a breaker in order to automatically close the grounding switch on the transmission line side of the breakers on both ends of a transmission line after the breaker is cut off, and then, automatically opening it through a timer. CONSTITUTION:When a ground fault occurs at the A point of a circuit 1, the breakers 3A1 and 3A2 on both ends of the transmission line of the circuit 1 are cut off. This cutoff is detected by limit switches 3L1 and 3L2. The closing coil 4C of a grounding switch is excited by the contact 10a of an auxiliary relay 10 to close a grounding switch 4A1. Then, the leader coil 4T of the grounding switch is excited by the a contact 4a of the grounding switch and the timer contact 11a through a timer 11 to automatically open the grounding switch 4A1. Thus, after the grounding switches 4A1 and 4A2 are opened, the breakers 3A1 and 3A2 are again closed by an automatic re-closing instruction 6.</p> |
