The invention concerns a motor starter circuit for an induction motor, particularly a single-phase AC induction motor, with a main winding (4) and an auxiliary winding (5) supplied with current, particularly AC, via current supply connections (24, 25), and with a starter switch arrangement (15), which serves the purpose of interrupting the current flow through the auxiliary winding (5) after the start of the motor, the starter switch arrangement (15) interacting with a measuring arrangement serving the purpose of measuring the voltage across the auxiliary winding (5).In order to optimise the motor starter circuit with regard to operation safety, a protection fuse (30) and a protection switch arrangement (47) are connected in series between the current supply connections (24, 25) so that, when the protection switch arrangement (47) is closed, the current flows in such a manner through the protection switch arrangement (47; 77) and the protection fuse (30) that the protection fuse (30) is triggered to interrupt the current flow.