207--DCMT Lab manual by Prof.A.A.Malgave

Experiment no. 1
Object Load test on DC Shunt motor.
Objectives To study the direct loading test of DC Shunt motor by Rope-Pulley arrangement method.
Theory             This is direct method of testing the motor in which the motor is loaded gradually from no load to full load. The pulley is fitted on the shaft of a motor. A rope or leather belt is wound round the pulley & its two ends are attached to two spring balances F1 & F2. The tension of the belt can be adjusted with the help of the wheel.             The force acting tangentially on the pulley is equal to the difference between two spring balance readings. i.e.       F = (F1 - F2)     If         r = radius of pulley in meters,             N = speed in rpm,
Advantages of Break load test. It is direct method of testing.Temperature rise of machine can be noted.Results are accurate.Any type of motor Shunt, Series or Compound can be tested.
Disadvantages of Break load test. Not suitable for large machines.Limitations…