| 摘要 |
<P>PROBLEM TO BE SOLVED: To solve the following problems: when a protective relay of a low-order load supply line fails, a high-order transformer protective relay (51P) operates as a backup; and when a corresponding load supply line has a fault in such a state, the high-order transformer trips, so that a power failure occurs also in other normal load supply line. <P>SOLUTION: A simple portable trip device is connected to a failed protective relay of a load supply line and a transformer protective relay (51P) that operates as a backup. The device trips the load supply line according to a signal from the transformer protective relay (51P) which has detected a fault of the load supply line. Afterward, if the fault continues, the device trips a high-order transformer. <P>COPYRIGHT: (C)2011,JPO&INPIT |
