Central inverters (also called string inverters) connect a string of PV panels and convert the DC electricity into AC. A single string- term used for solar panels connected in series - usually has a maximum of about ten solar panels. How Does a Solar Inverter Work? It works by taking the variable direct current from the solar panels and changing it into alternating 120V/240V or alternate current output. Most home appliances run on alternate current but not direct current.