I have optimized the design of the RS485 piggyback for the Sunny Boy inverter. An isolated RS485 driver with integrated DC/DC converter is used and replace the external expensive 5V DC/DC converter of the first version.
If there are some people interested in an assembled PCB than I can order a batch of PCBs and [...]
After I found out the pinout of the Sunny Boy 2100TL inverter I build the UART piggyback and it is working fine. Now, it’s time to build the RS485 version.
Because I didn’t want to use an external power supply for the galvanic isolated output side I used an (expensive) [...]
Last month I did buy a 2kW photovoltaic system for my house. To connect the pv panels to the grid I bought the Sunny Boy 2100TL inverter from SMA. Unfortunately, it comes without any communication interface in standard configuration. The price for the so called RS485 piggyback interface card is around 90 Euros. On sales [...]