Bruzzone, P. GWesche, R.Uglietti, D.Bykovsky, N.2017-09-052017-09-052017-09-05201710.1088/1741-4326/aa7babhttps://infoscience.epfl.ch/handle/20.500.14299/140146WOS:000406105300001High temperature superconductors (HTS) may become in future an option for the superconducting magnets of commercial fusion plants. At the Swiss Plasma Center (SPC) the R&D activity toward HTS high current, high field cables suitable for fusion magnets started in 2012 and led in 2015 to the assembly of the first 60 kA, 12 T prototype conductor. The cable concept developed at the SPC is based on the principle of 'soldered, twisted stacks' of REBCO tapes. The required number of stacks is assembled in a cored flat cable, cooled by forced flow of supercritical helium. The sample environment of the test facility at SPC has been upgraded with a HTS adapter and a counter-flow heat exchanger to allow testing the HTS sample in a broader range of temperature (4.5 K-50 K) using the existing, NbTi based superconducting transformer and the closed loop refrigerator.high temperature superconductorsfusion magnetshigh current cablestext::journal::journal article::research article