For contactless current measurement at a first primary conductor that is configured to conduct a first primary current having a first current strength, and at a second primary conductor that is configured to conduct a second primary current having a second current strength, a ring-shaped magnetic core that encircles the first primary conductor and the second primary conductor detects the total magnetic field in the magnetic core and generates from the total magnetic field detected in the magnetic core a signal corresponding to the superposition of the first current strength and the second current strength. The first or second magnetic field component or individually both are also detected, and from the detected first or second magnetic field component or from both, a signal corresponding to the first current strength or a signal corresponding to the second current strength or both are generated.