Yes. The L400 and T400 are capable of controlling inverters. The inverter will be wired to the ATS, hence the ATS recognizes it as the 3^rd source of supply making it priority 2. In other words when utility power supply is lost the ATS starts up the inverter and powers the load, and if auto generator is used, when the inverter battery is weak the ATS starts up the generator and the load is powered by the generator and inverter starts charging the batteries, when utility supply is restored the generator is shut down and the load is powered by utility supply.