Abstract: A device for imposing a torque load upon rotating machinery comprises a rotary unit and plural electromagnetic units. The rotary unit includes a shaft and conductive disks discretely fastened thereto. Each electromagnetic unit includes a bracket-shaped magnetic core and one or more ferromagnetic pieces discretely fastened thereto. The device's shaft is joined end-to-end to the motor's shaft, permitting integral axial rotation of the device's shaft, the disks and the motor's shaft. Each electromagnetic unit is placed so that the core “brackets” the two extreme disks, while each piece is between two disks. During rotation, a wire (coiled around each core) conducts current of selected amperage so as to generate a magnetic field of sufficient intensity that a magnetic flux circuit is formed through the stationary core and pieces and the rotating disks, resulting in a Lorentz force associated with the magnetic field and eddy currents engendered in the disks.