The graph shown below is related to which type of class in the motor
Right Answer is:
Continuous Duty With the variable load
Continuous Duty with Variable Load:- In this type of duty, the load is not constant but has several steps in one cycle. This cycle of loading repeats for a longer time. If the load variations are slight the motor of the continuous rating of the highest load may be chosen from the available catalog.
However, if the variations in the load cycle are large the machine undergoes a continuous change of temperature. However, after several cycles of operation, the motor selected may attain a steady-state value. The thermal calculations of the motor are involved. The selection of a motor based on heating is rather involved and a difficult task. Therefore some simplified criteria may be evolved for selecting a motor for this duty. The motors operating for such types of duties will have poor efficiency and also poor power factor.
The selection of motor for this type of duty may be based on average power or average current method.