DC BUS VOLTAGE INPUT INTO RAT AUTO-DEPLOY

A system includes a first AC bus configured to supply power from a first AC power source. A second AC bus is configured to supply power from a second AC power source. A first transformer rectifier unit (TRU) connects a first DC bus to the first AC bus through a first TRU contactor (TRUC). A second TRU connects a second DC bus to the second AC bus through a second TRUC. A first voltage sensor is connected to sense voltage of the first DC bus. A second voltage sensor is connected to sense voltage of the second DC bus. A ram air turbine (RAT) automatic deployment controller is operatively connected to the first voltage sensor and to the second voltage sensor to automatically deploy a RAT based on the combined status of the first voltage sensor and the second voltage sensor.