In this work an inductive contactless method for the quality control of long length filamentary Bi-2223 tape superconductors is investigated. In a continuous process, the magnetic field of induced shielding currents is determined with a single Hall probe or a Hall probe array. The magnetic field along the length of the conductor is used to investigate the length homogeneity of the critical current and to locate defects in the tape, the cross profile gives information about the filament

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... The magnetic field along the length of the conductor is compared with the resistively determined critical current. Resistiv measurements on short tape sections with a length up to 0.5 m, are used to demonstrate the suitability of the inductive method. Measurements on different types of tape conductors show a correspondence between the magnetic field variation along the length and the resistively determined critical current. This proves that the magnetic field of the induced shielding currents is suitable to deterrnine the homogeneity of the critical current, if filaments are coupled due to the experimental conditions (dB/dt). The method was applied to long tapes (up to 16m) with twisted and untwisted filaments. The typical defect structures which are observed are bubbles and variations of the critical current, caused by the rolling process during the tape production.