Abstract: A power conservation circuit having a low voltage power supply for powering a first and second switch. The first switch connects output terminals to either the low voltage power supply or a powered device. The second switch connects or disconnects power to the powered device. The low voltage power supply provides a sensing current when a load is placed across the output terminals. The current goes to a control switch which causes the first and second switches to switch into the ON state. A sensing circuit detects the continued draw of current from the powered device while a load is present. The sensing circuit maintains the control switch in the ON state. In the absence of any loads on the output terminals, the sensing circuit causes the control switch to switch the first and second switches into the OFF state. In the OFF state, power is disconnected from the powered device thereby conserving power when there is no load requesting the use of the powered device.

Abstract: A power conservation circuit for a battery-powered voltage inverter is capable of conserving battery power. In a first embodiment, the circuit includes a switch, connected between the input terminals and the output terminals, for switching the circuit between an ON state wherein AC voltage is connected to the output terminals, and an OFF state wherein the inverter is disconnected from the battery. A first sensor senses in the ON state the absence of a load connected to the output terminals and switches the circuit from the ON state to the OFF state. A second sensor senses in the OFF state the presence of a load connected to the output terminals and switches the circuit from the OFF state to the ON state. The switch includes a relay having a pole terminal connected to the output terminals, a first contact terminal connected to the AC output of the inverter, and a second contact terminal connected to battery voltage.