Method of Measuring Torque-Speed Characteristics of Fractional Horsepower Motors

Abstract

In determining experimentally the speed-torque characteristics of fractional horsepower servomotor, accurate measurement of small torques in necessary. The paper here describes the accurate measurement of small torques of the order of 50 gm-cm or even less. Principal of eddy-current damping is used on a thin metallic disc rotating in the air-gap of an electromagnet and the reaction torque due to eddy-currents in the metallic disc is balanced with the standard weights placed in a scale-pan.