We present electrical AC loss measurements of multifilamentary Ag sheathed Bi(2223) samples in self field and under a small external DC magnetic field. The I-V measurements are performed using the AC transport method. We use a dual channel high stability lock-in amplifier in order to achieve the highest phase resolution. Tape samples of 1,19, 37 and 55 filaments are compared. We use current amplitudes under and above the critical current at power frequency. The AC losses are analyzed as functions of the number of filaments. This effect is studied in self field and also under a small DC magnetic field of 10 mT, applied perpendicular to the tape surface. The AC losses of those multifilamentary tapes are comparable to Norris predictions of hysteretic losses. The evolution of the AC losses brings into consideration the sc/Ag ratio and the twisting of the filaments. The Ag sheathed multifilamentary Bi(2223) tapes are prepared by Professor Flukiger's team at the University of Geneva and the measurements were performed at the EPFL.
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