The SMA Sunny Boy 1.5, 2.0 or 2.5 can be connected to the router via an ethernet cable, or wirelessly using Wi-Fi. If there is no data coming thorugh to the internet, it can help to reset the inverter. This means: removing the power to the unit fom both sides (both from the grid as well as from the solar panels), and then reconnecting them again. 

In order to perform a reset, follow these steps