What is the reason behind short circuit in armature?
(a) Insulation failure between two commutator bars
(b) Insulation failure between two turns of a coil
(c) Two or more turns of the same coil getting grounded
(d) Insulation failure between two commutator bars, two turns of a coil or the same coil getting grounded
This question was posed to me in an interview for internship.
My doubt is from Armature Reaction -1 in division Armature Reaction of DC Machines