An exemplary magnetic actuator for a circuit breaker arrangement includes a coil, a core with a groove for accommodating a section of the coil, and a movable plate configured to be attracted by the core. When a magnetic field is generated by the coil, the movable plate actuates the circuit breaker arrangement based on the attraction to the core. The magnetic actuator also includes a position locker for locking the coil in the groove. The position locker having a locking part protruding away from the core and over a section of the coil not accommodated in the groove.