Question

What type of core is employed when the performance standard required is not so high?

(a) rectangular strips

(b) c-shaped sections

(c) rectangular strips or c-shaped sections

(d) rectangular strips and c-shaped sections

I got this question in an interview for job.

This key question is from Design Principles in section Design of Current Transformers (CT) of Design of Electrical Machines

Answer 1

Correct answer is (c) rectangular strips or c-shaped sections

The best explanation: Ring core type is used only for the high performance operation. The rectangular strips or c-shaped sections are used when the standard of performance required is not so high.