APPARATUS AND METHOD FOR MONITORING AN INPUT VOLTAGE OF A DIGITAL PROTECTION RELAY

摘要

PURPOSE: An input voltage inspection device of a digital protective relay and a method thereof are provided to improve the monitoring and control function of a digital protective relay by using a digital input only when a voltage value is greater than a threshold value. CONSTITUTION: A voltage detecting part(115) detects the DC voltage of a digital input. A calculation part(130) executes a calculation by using the digital input only when the DC voltage of the detected digital input is greater than a threshold value. A digital output part(160b) outputs a control signal regarding the operation of the digital protective relay by receiving calculation result from the calculation part. The voltage detecting part includes a multiplexer(116) and an A/D converter(117) which converts CB Close DI and CD Open DI into a digital signal.