| 摘要 |
PURPOSE: A digital protection relay is provided to prevent a circuit breaker from being tripped due to an error by including a microprocessor which outputs a trip control signal when an inrush current is generated. CONSTITUTION: A current detector(1) provides an analog current detection signal about a current value in a circuit. An analog-digital converter(2) converts the current detection signal from the current detector into a digital signal and outputs the digital signal. A breaker state input circuit unit(3) receives on, off, or trip operation signal. A microprocessor(4) outputs a trip control signal which trips the circuit breaker. An output circuit unit(5) transmits an on control signal or trip control signal received from the microprocessor into the circuit breaker. |
