A series of round-robin measurements of the self-field ac loss of Bi-2223 tapes

A round-robin of self-field ac loss measurements on Bi-2223 tapes has been performed for the first time, under the Brite EuRam research programme SACPA, Excellent agreement on loss data has been obtained by the four measurement partners. This further confirms the validity of the electrical technique employed and allows reliable comparisons between the loss data of the individual partners in the project. The different measurement systems and sample mounting procedure are described. For accurate measurement of the loss voltage to the required sensitivity, only a lock-in technique was suitable. The phase of the applied current was measured with a Rogowski coil (with or without compensation) or a non-inductive resistor.