The best answer with some examples and necessary considerations are mentioned in abaqus document 1.8.4 or go directly to examples - abaqus benchmarks manual.
I cannot find the usersubrouttne UDEMPOTENTIAL for the examples input files for 1.8.5 TEAM 6: Eddy current simulations for spherical conductors in an oscillating magnetic field. Could you help me find the contents in the subroutine file? Thank you.