Transformer MCQ Part 7

A 220/1100 V transformer takes no load current of 7 A and absorbs 200 W. What is value of magnetizing current:

1. 4.89 A
2. 5.89 A
3. 6.94 A
4. 7.33 A

Correct answer: 3. 6.94 A

Solution:

Active components of current = I_W = W₀/V₁ = 200/220 = 0.90 A

Magnetizing current = √(I_o² – I_w²) = √(7² – 0.90²) = 6.94 A