Question

what is the first step in drawing the armature characteristic?

(a) If is made 0

(b) Field current is adjusted to give Voc equal to rated value

(c) Switch connecting armature circuit with external circuit is made open

(d) Cannot be determined

I have been asked this question during an online exam.

This intriguing question originated from External and Armature Characteristics of DC Generator topic in chapter DC Generator of DC Machines

Answer 1

The correct answer is (c) Switch connecting armature circuit with external circuit is made open

The explanation is: While drawing armature characteristic, switch of armature circuit is made open so that armature current is set to 0. Then, field current is adjusted to give Voc equal to rated value. Switch its then closed.