Smart grid tie inverter is a compact unit that directly converts direct current into alternating current for powering devices and/or office equipments and connecting to utility grid. The AC output of Smart Micro inverter is synchronized and in phase with the power grid. The voltage of matched solar panel:Vmp: 17-21V, Voc: 20-24V. AC output voltage: 120VAC(90-140VAC). Frequency Range: 48Hz 62Hz Auto. MPPT range: 15.5-22V. Vmp (from a solar panel) must be in the MPPT range to ensure the good output efficiency. Please note that this inverter is designed for solar panels, which can be suitable for 12V Solar Panels, Vmp is 17-20V and Voc is 20-24V. When using 12v battery as input, the inverter it will not reach the max power point. We will suggest using 24v battery as input source to get better output power. There is always a loss in power in converting from DC to AC. Also through heat loss of energy. So if you are expecting to receive they are 100% out of the machine it will not give you that. Solar panel has the loss too, so please do not calculate the efficiency as inverter output power/solar panel specification. Because solar panel and inverter all have own efficiency. Collect several customers error feedback, most of which stop working are with the wrong solar panel voltage input? 2. Please use a 10 square cable, the cable length is not recommended to exceed 4M. Disconnect the DC terminal wiring. If the cable is too thin or the connection is loose, the inverter will be damaged. How to easily set up Y&H Grid Tie Inverter? 1: Use 150W-600W Solar Panel, Vmp17-20V; Voc 20-24V. 2: Red terminal: Connect DC positive, black terminal: Connect DC negarive.. Be sure to unplug! Otherwise it will be short-circuited. AC The output need to be connected to the mains power. 3:AC socket: Connect to the mains. The AC cable to the inverter 3 foot outlet, then the AC cord to the home 3 pin AC outlet. 4: The switch of the home socket must be turned on.