Electrical Contact Resistance of Multi-Contact Connector in Semi-Retractable Current Lead

Heat leakage through current leads is the dominant contributor to cryogenic heat load for various high field magnets. The semi-retractable current lead is a good option because the conductive heat leak can be eliminated after the magnet is charged. It is composed of a normal metal element and an HTS element. The normal metal element is disengaged from the HTS element through the multi-contact connector without disturbance to the insulating vacuum space and without requiring complete removal of the normal metal element. In this paper, the electrical contact resistance of multi-contact connector is measured to confirm the feasibility of our application. The effects of current level, operating temperature and size on the electrical contact resistance in a lockable set are also discussed.