Question

Why field winding of a DC series motor is provided with thick wire?

(a) As it carries large load current

(b) To provide large flux

(c) In order to reduce eddy current to provide large flux

(d) To reduce the of insulting materials

This question was addressed to me by my school teacher while I was bunking the class.

I want to ask this question from DC Motor Basics -2 in portion DC Motors of DC Machines

Answer 1

Right option is (a) As it carries large load current

To elaborate: In DC series motor, the cross-sectional area of wire used for field coils has to be large because the in this case field coils carry the load or armature current. As the cross-sectional area is large, the resistance is minimum and series voltage drop is also minimum.