Current leads for the LHC magnet system

The LHC current lead project is now entering into the stage of procurement of the components for integration into the machine. About 3300 current leads with ratings ranging from 60 A to 13 000 A will be required for powering the numerous electrical circuits. The main design choices have been taken on the basis of the outcome of an intensive R&D program covering the characterization of suitable High Temperature Superconducting (HTS) materials for current leads, the validation of lead design options and the,measurement of the thermo-electrical performance of prototypes tested under various operating conditions. Helium gas cooled leads integrating HTS material at the colder end will be used for high current leads (currents greater than or equal to600 A), while the corrector dipole magnets (60 A-120 A) will be powered via specifically designed conduction-cooled resistive leads. An outline. of the retained designs will be presented, together with required, schedule for lead manufacture.