The OutBack G-Series inverters are the grid-interactive versions in OutBack’s FX inverter line. Available in either sealed (GTFX) or vented (GVFX) models, these inverters allow you to sell solar, wind, and/or hydro power back to the utility grid. If the utility power goes down, the inverter will automatically switch to battery power and your renewable energy source(s) to run your critical loads. The inverter can be set up so that either utility power, or your renewable source, can be used to recharge the battery bank after an outage. AC power is seamlessly switched between utility and battery power through the inverter’s built-in 60A transfer switch. With the OutBack grid-interactive system, backup AC power is made available 24 hours a day in the event of a utility outage, providing reliable power and peace of mind. At night, the inverter's automatic power save mode ensures that energy is not wasted by needlessly charging your batteries from the utility grid. Daily energy production efficiency is within a few percentage points of batteryless grid-intertie systems (depending on the condition of the battery bank). Up to two grid-interactive FXs can be combined and wired or “stacked” for 120/240V output. The Grid-Tie FX Series Inverter/Chargers can be stacked in Classic Series only, which is limited to two grid-interactive FXs. Note: The FW-X240 Auto Transformer cannot be used for stacking with a Grid-Interactive FX system. However, the FW-X240 can be used to step-up the AC output of a single Grid-Interactive FX system from 120VAC to 240VAC. These inverters are not recommended for off-grid use. See page xx for OutBack off-grid inverter models. OutBack G-Series inverters come with a standard 2-year warranty with an optional 3-year extension (5-years total). A 10-year warranty is available for California residents. ETL Listed to UL standards.