A dc shunt motor drives a centrifugal pump at a speed of l000 rpm when the terminal voltage and line currents are 200 V and 50 A, respectively. The armature and field resistances are 0.1 ? and 100 ?, respectively.

a. Design a starting resistance for a maximum starting current of 120 A in the
armature circuit.
b. What resistance should be added to the armature circuit to reduce the speed to
800 rpm?
c. If the terminal voltage is reduced by 25%, what is the speed of the motor?




Trades & Technology

You might also like to view...

SAE 30 oil is contained inside a cylinder with inside diameter of 1-in and length of 1-ft. What is the pressure required to decrease the volume of the oil by 2%?

What will be an ideal response?

Trades & Technology

Where is food stored in monocot and dicot seeds?

What will be an ideal response?

Trades & Technology

One purpose of filters is to:

a. add air or other gases to a process stream b. remove moisture from a process stream c. remove solid particles from a process stream d. none of the above

Trades & Technology

Final adjustment of a deck slab's elevation is done using _____.

a. hanger clamps b. wedges c. haunches d. leveling screws

Trades & Technology