Slip-ring motor tests

This is a very useful nomogram to determine the performance of a motor with the help of only no-load and short-circuit test results. In slip-ring motors, it also helps to determine the external resistance required in the rotor circuit to control the speed of the motor and achieve the desired operating performance. Slip-ring motors are discussed in Chapter 5. The concept behind this nomogram is that the locus of the rotor and the stator currents is a circle. Consider the equivalent circuit of an induction motor as shown in Figure 1.15, where... 

Open-circuit voltage ratio test for slip-ring motors 11/264... 

On a wound rotor motor, the following additional checks are also necessary after removing the slip-ring covers, prior to testing ... 

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