Inverter for photovoltaic systems

The inverter (1) has inverter inputs (7.1, 7.2), an inverter output (9), and an inverter element (3) with a direct-voltage input (8). A control electronic system having a microcontroller (5) monitors direct voltage lying at the direct-voltage input and mains voltage and/or mains frequency of a network. The system permits switches (K1, K2) to separate one of the inverter inputs from the direct voltage input when the voltage lying at the direct-voltage input exceeds upper threshold and/or the mains voltage or mains frequency lies beyond standard voltage and/or standard frequency range. An independent claim is also included for a method for controlling an inverter for a solar panel.