Application problems of high-current superconducting materials

High-current/field application problems for both conventional and high-temperature (HTS) superconductors are discussed briefly. As an illustration, it is shown how one can avoid the control of the critical current of full Rutherford cables, by measuring the critical current of extracted strands. Residual-resistance ratio adjustment is also shown to be necessary, in order to achieve the required high ramp rate properties of the SC material. Examples are given of how a too high or a non-uniformly distributed contact resistance between the HTS and the normal metal (Cu) structure can cause serious problems when HTS materials are used at high currents.