Question

What is the formula for the inside diameter of the low voltage windings?

(a) inside diameter = diameter of the circumscribing circle + pressboard thickness insulation between l.v winding and core

(b) inside diameter = diameter of the circumscribing circle – pressboard thickness insulation between l.v winding and core

(c) inside diameter = diameter of the circumscribing circle + 2*pressboard thickness insulation between l.v winding and core

(d) inside diameter = diameter of the circumscribing circle – 2* pressboard thickness insulation between l.v winding and core

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Answer 1

The correct answer is (c) inside diameter = diameter of the circumscribing circle + 2*pressboard thickness insulation between l.v winding and core

The best explanation: For calculating the inner diameter, first the diameter of the circumscribing circle is obtained using the corresponding formula. Then the pressboard thickness insulation is calculated.