Question

Copper shading bands are _________

(a) placed as resistance

(b) placed as wire

(c) placed outside the central limb

(d) placed around central limb

The question was posed to me in an interview for job.

I need to ask this question from Lag Adjustment Devices topic in chapter Measurement of Power and Related Parameters of Electrical Measurements

Answer 1

Correct choice is (d) placed around central limb

The best explanation: The central limb of a shunt magnet consists of copper shading bands. They can be moved up or down by making use of the central limb. Figure below illustrates the use of copper shading bands.