| 摘要 |
The control and monitoring system, for power networks, has its receiver and evaluator coupled to a rectifier output. The rectifier input is coupled to the power network. The evaluator outputs are connected to a differential transistor pair which operates the relay whose contacts separate the load from the network. The relay and transistor pair are bridged by a capacitor which is charged over a resistor from the rectifier output. To prevent this capacitor operating the relay when the supply power fails a diode is connected across the resistor to provide a discharge path for the capacitor in the event of failure. |
