No-Load Test: At no-load the machine runs at very small slip sufficient to provide power for windage and friction loss, core loss and also a certain amount of stator copper loss, which has to be, accounted for because of the large no load current.
With low slip, the following approximation will hold good.
R2?(1/s-1) is very high
R2?/s>>X2?
With these approximations the necessary formulae for finding out Xm will be given while conducting the no-load test.
