The apparatus has an inverter housing (7) provided with a safety fuse (8). Positive direct current voltage (Plus Uzwk) or negative direct current voltage (Minus Uzwk) is grounded through the safety fuse. The safety fuse is provided in a plug connector part that is equipped with three plug connectors. The plug connectors are plugged at an outside of the inverter housing. Three mating contacts corresponding to the plug connector part are provided on the inverter housing. The safety fuse is located in a cup-like part, and an inverter is equipped with a transformer. An independent claim is also included for a method for converting a photovoltaic current of a photovoltaic generator.