Question

What is the value of permissible stress for steel wire for the diameter of branding wire of 0.5-1.2 mm?

(a) 570 NM per m^2

(b) 600 NM per m^2

(c) 650 NM per m^2

(d) 700 NM per m^2

This question was addressed to me in an internship interview.

My doubt stems from Bracing of Rotor Windings topic in section Aspects of Design of Mechanical Parts of Design of Electrical Machines

Answer 1

The correct answer is (b) 600 NM per m^2

For explanation I would say: The value of permissible stress for steel wire for the diameter of branding wire of 0.5-1.2 mm is 600 NM per m^2. The value of permissible stress for steel wire for the diameter of branding wire of 1.5-2 mm is 570 NM per m^2.