DC Machines 1

Which of the following statements are correct?

• Construction of DC Motor and DC Generator are same

• A machine can be made to run as a Motor or Generator

• The voltage that is generated in the armature are always AC

• At no load the efficiency is always zero

Which generator has voltage booster characteristics?

• DC Shunt Gen

• DC Series Gen

• DC Cumulative Compound Gen

• DC Differential compound Gen

The first DC generator developed by Thomas Alva Edison is a (a)   Generator

Which generator type is known for its ability to maintain voltage under varying load conditions?

• DC Shunt Gen

• DC Series Gen

• DC Cumulative Compound Gen

• DC Differential Compound Gen

Which is not a part of constant loss?

• Series Field Cu loss

• Shunt Field Cu Loss

• Friction loss

• Hysteresis loss

A DC machine has a field resistance of 300 ohms and a critical resistance of 450 ohms. Is it possible for voltage to develop inside the generator

• Yes

• No

Which of the following is essential for self excitation in a shunt generator

• Residual voltage

• Critical resistance less than field resistance

• External field current

• All the given choices

What are the sources of internal voltage drops

• Aramture reaction

• Armature resistance

• Armature reactance

• Armature impedance

Right rule applied for

• Generator

• Motor

• Transformer

• All the given devices

Armature reaction is due to

• Armature voltage drop

• Armature loss

• Armature field

• Armature winding damage