Tripp Lite's APS1012SW 3-function DC-to-AC inverter with auto line-to-battery transfer and integrated charging system serves as an extended run UPS, a standalone power source or an automotive inverter. Supplies up to 1000 watts of continuous 120V AC power. When the AC cable is connected to a live wall socket, utility power passes through to connected equipment and the battery set is recharged via 3 stage, 4/40 amp selectable charging system. In UPS mode, the APS system responds to blackouts and brownouts with an uninterrupted transfer to battery-derived AC output. Includes a set of high current DC input terminals for simple installation (user supplies batteries and cabling). Reliable large transformer design with efficient sine wave output and frequency control powers resistive electronic loads or large inductive motors, compressors and other items with high current needs on start-up. Supports an unlimited amount of runtime with any number of user-supplied batteries. Highly adaptable to a variety of applications and site conditions.