Yes, the wall switch "routes" 12 volt power to the power supply circuits in the roof antenna amplifier (white box on the Winegard Sensar antenna models) via a powered closed relay and "deselects" the cable input on the outside wall when the green light is on.
When you turn it OFF, the wall plate relay is deenergized and 12 volt power is disconnected from the roof; the 12 volt power draw is then zero amps.
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