| 摘要 |
PURPOSE:To promptly release different system linking by turning off a semiconductor switch by an AND condition between an opening command signal and a current detection signal of a loop switch. CONSTITUTION:When an opening command is given to a loop switch 11 with an on-command given to a thyristor switch 19, the loop switch 11 is opened, and the current flowing therethrough is bypassed through the thyristor switch 19. Under this condition, when a closing command is given to section switches 5 to 10, they are closed to allow a current to flow because a different system is linked in this point of time, and when the current reaches a current detection level, a current detection signal is output from a current detecting circuit 21. As a result, the output of an AND circuit 22 becomes '1', which is the OFF command to cause a trigger circuit 23 to turn off the thyristor switch 11. |
