A method and current sensor arrangement for measurement of a primary current in a primary conductor which is magnetically coupled to a secondary conductor via a ferromagnetic core, with a voltage of a specific amplitude being applied to the secondary conductor, such that a secondary current flows for remagnetization of the ferromagnetic core, and the secondary current is measured during the remagnetization of the core, in order to obtain a first measured value. The voltage polarity is then reversed such that a secondary current flows for renewed remagnetization of the ferromagnetic core, and the secondary current is measured during the remagnetization of the core, in order to obtain a second measured value. The primary current is calculated as a function of the first and of the second measured value, with the polarity reversal being carried out at least once at a time which occurs before that time at which the ferromagnetic core reaches its saturation magnetization.