Automatic three-phase squirrel-cage induction motor test assembly for motor thermal behaviour studies

This paper presents a laboratory assembly to perform, automatically, three-phase squirrel cage induction motor load tests. Besides the motor, mechanical load (fan), drive and electrical protection equipment, the assembly comprises a 12 bits data acquisition system, a software controlled electronic driving system, temperature sensors and a microcomputer. It is useful for fast and reliable motor part temperatures acquisition during any load test proposed via a computer keyboard allowing for the data storage for motor thermal behavior studies. The performance of the assembly was checked by performing load tests according to the duty types proposed in IEC Publ. 34-1, Rotating electrical machines, Part 1: Rating and Performance, 8th edition, 1983