Page 91 - CITS - Electrician - Trade Practical
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ELECTRICIAN - CITS



           Tabular column:

             Sl.No  Supply Voltage (V)  Starting current (I) Field current (I ) Load current (I )  Speed (RPM)
                                                                         F                L













           TASK 4 :Start & run of DC compound motor
           1  Make the connections of DC compound motor with 4 point starter as per circuit diagram.

           2  Ensure that there is no mechanical load on the motor. (However, motor can be started with nominal load).
           3  Check the connections & connect the motor to DC power supply unit through DPST switch.
           4  Start the motor by operating DC 4 point starter.
           5  Record the starting & running current, voltage and speed of the motor.
           6  Now apply the mechanical load gradually on the motor and check the speed of motor by tacho meter. (Note-
              Compound motor is capable to take heavy loads).
           7  Switch OFF the supply and disconnect the motor.























           Tabular column:

             Sl.No  Supply Voltage (V)  Starting current (I) Field current (I ) Load current (I )  Speed (RPM)
                                                                         F                L









           Safety precautions:
           1  Ensure proper foundation & fixing of DC motors.

           2  Never start DC series motor without mechanical load.
           3  Never start DC motors without starter & protective MCB.
           4  Ensure proper earthing for motors.
           5  Do not load the motors excessively.


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                                    CITS : Power - Electrician & Wireman - Exercise 37
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