Precision Coaxial Manganin Shunts

High precision, four-terminal resistors (shunts) of coaxial design have been developed at Argonne National Laboratory (ANL) for measuring and controlling constant or pulsed magnet currents. Air or water-cooled shunts for currents between 50 A and 10 kA have been built. Their frequency response ranges from dc to tens of kilohertz, and their resistance is reproducible within ±0. 001%. The resistance-stress coefficient of shunt-manganin was determined for compressive stresses applied transverse to the direction of current flow.