| 摘要 |
PURPOSE:To make it possible to perform function test and to confirm output contact through a relay unit itself by making it possible to apply a test signal onto a trip mechanism under steady state. CONSTITUTION:Upon occurrence of abnormality in a power system 1, an operation value comparing circuit 5 causes an output circuit 13 to function so that an output contact 131 is closed. Consequently, output of an amplifier circuit 7 increases and a microcomputor 6 judges a system abnormality and causes the output circuit 15 to function so that an output contact 151 is closed thus exciting a trip coil 20. Upon provision of an operation command onto a switch 101 in a switch section 10, a test signal generating circuit 9 provides a test signal to the operation value comparing circuit 5 in order to perform self inspection of the operation value comparing circuit 5, the output circuit 13 and the output contact 131. Upon provision of an operation signal to a switch 102, a test signal is provided to the amplifier circuit 7 in order to perform self inspection of an A/D converting circuit 8, the output circuit 15, the output contact 151 and the microcomputor 6. |
