A device (340, 440, 540) is connected to an output terminal of a controller (330), having a single input terminal connected to a first power terminal of an external power source (305) which outputs an AC voltage between the first power terminal and a second power terminal. The device includes a bleeding circuit (342, 442, 542), and a switching arrangement (344/346, 444/446, 544/546) to detect whether the controller powers a load (320 or disables the load. When the controller is in an OFF state, the switching arrangement connects the bleeding circuit between the output terminal of the controller and the second power terminal to provide a current path between the output terminal of the controller and the second power terminal. When the controller is in an ON state, the switching arrangement disconnects the bleeding circuit between the output terminal of the controller and the second power terminal.