Automatic change-over relay system for supplying current from a spare current sourceupon the failure of current supplied from a main current source

摘要

625,298. Systems depending on the use of two or more sources. WILCOLATOR CO. Dec. 24, 1946, No. 37903. Convention date, Aug. 21, 1945. [Class 38 (iv)] Upon the failure of a main inverter 14, which may be used in heavy aircraft, and which is supplied through a relay 16 energized through normally closed contacts 38 of a D.C. relay 40, a spare inverter 18 is supplied with D.C., after a time delay determined by. a relay 58 which is set in operation upon the de-energization and consequent closing of an A.C. relay 50 normally energized from the output of the main inverter 14 through line 72. Upon closing a main switch 32, relay 16 is energized from a D.C. bus-bar 12 through terminal 34, contacts 38 of relay 40, terminal 44 and line 46, and closes contacts in the input and output lines of main inverter 14. Upon failure of this inverter, the relay 50 closes, and connects the D.C. supply through contact 62 of relay 40 to heater 66 of delay switch 58. Contact 56 on a bimetallic strip then moves down and, if the inverter failure persists, engages contact 78. D.C. is then connected through terminal 82 to a relay 20 which closes the input and output circuits of the spare inverter 18. Relay 40 is also energized and contact 62 moves down to break the supply to the heater, but the supply to relays 20 and 40 is maintained through contact 38 which moves to its lower position at the same time breaking the supply to relay 16 of the main inverter. A signal 22 operated by a relay 23 indicates inverter failure.