Failure Detector And Shutdown Circuit For Constant Voltage Transformer Power Supply
Original Publication Date: 1979-Aug-01
Included in the Prior Art Database: 2005-Feb-20
A circuit is disclosed which allows the shut down of a constant voltage transformer power supply when a fault (undervoltage, overcurrent or thermal) is sensed, by removing the AC voltage from the power supply. This is accomplished by a unique circuit breaker arrangement comprising one DC and two AC circuit breakers 1, 2 and 3, respectively, ganged together. When a fault is detected, silicon controlled rectifier Q5 is turned on. This causes the DC circuit breaker 1 to open. Since the DC circuit breaker 1 is ganged to the two AC circuit breakers 2 and 3, the AC circuit breakers open up, thereby disconnecting the AC voltage to the power supply, as represented by lines 4.