Electrical Machines Questions and Answers – DC Motors
Operating Characteristics of DC Motors
0%
A dc shunt motor is connected to the source through 3point starter. Suddenly if we starter handle is moved fastly from off to on position, then
Correct!
Wrong!

How will the speed torque characteristic of a dc shunt motor and cumulatively compound dc motor perform at no load?
Correct!
Wrong!

For a dc shunt motor of 5 kW, running at 1000 rpm, the induced torque will be
Correct!
Wrong!

For a 100 hp 250 V, compound dc motor with compensating winding has a field current of 5 A to produce a voltage of 250 V at 1200 rpm. What will be the shunt field current of this machine at no load?
Correct!
Wrong!

A student is given a differential compound motor and he has been asked to make it start. How will he try?
Correct!
Wrong!

It is advised not to run dc series motor with no load. Why?
Correct!
Wrong!

It is impossible to start a differential compounded dc motor.
Correct!
Wrong!

The flux and the internally generated voltage of a dc machine is a ________ function of its magnetomotive force.
Correct!
Wrong!

The torque vs armature current of a differential compound motor in the strong field is
Correct!
Wrong!

Mark the correct option which affects the terminal voltage of a dc shunt motor.
Correct!
Wrong!

The torque characteristic is best described for a dc series motor with respect to armature current is
Correct!
Wrong!

The speed torque characteristics of the dc motor is best described by following the equation
w=(Vt/k*flux)Ra*T/((R*flux)^2)
w=(Vt/k*flux)Ra*T/((R*flux)^2)
Correct!
Wrong!

Choose the best option which identifies about the below characteristics.
Correct!
Wrong!

Identify the speed torque characteristics of a dc series motor.
Correct!
Wrong!

The speed torque of the differential compound dc motor is shown below. What conclusions can be made?
Correct!
Wrong!
