Dual isolated power supply inputs

A power supply system for providing power from either a first power supply or a second power supply to an ultimate rectified output. The system consists of a first switch that couples the rectified output of the first power supply to the ultimate rectified output, and a second switch that couples the rectified output of the second power supply to the ultimate rectified output. When the first power supply is providing a voltage within a predetermined window and the first switch is closed, the first power supply provides an inhibit signal to the second switch of the second power supply that prevents the second power supply from providing power to the ultimate rectified output. Similarly, when the second power supply is providing a voltage within a predetermined window and the second switch is closed, the second power supply provides an inhibit signal to the first switch of the first power supply that prevents the first power supply from providing power to the ultimate rectified output. The first and second power supplies are electrically isolated and the inhibit signals are transferred without conducting electrical current between the first and the second power supplies.