Circuit arrangement for connection to an electrical circuit and electrical circuit

An electrical circuit (10) is described which includes a transformer (12) with primary winding (13) connected to the electric power grid (17) and secondary winding (14) connected to a power converter (19) with a capacitor (20). It includes a circuit arrangement (25) which is connected to the electrical circuit (10). The circuit arrangement (25) has a primary winding (13) coupled to the auxiliary winding (27), which is connected to a switching device (28).