Electrical Measurement and Measuring Instruments — Winter 2021

Describe the working principle of Hall effect transducer.

What is standard of measurement? Describe various standards of measurement.

Define transducer and classify transducers on different basis.

Why PMMC instrument cannot be used for ac measurement?

Explain how strain gauges are used for the torque measurement.

Define following term.

Accuracy (ii)Drift (iii)Sensitivity (iv)Reproducibility (v)Precision (vi)Threshold (vii)Fidelity.

Explain principle and construction of RTD.

State different methods used to measure low, medium and high resistance.

Draw the circuit diagram of Anderson’s bridge.

Explain the working of electrodynamometer type wattmeter.

Why secondary of current transformer should not be open, when primary is energized?

Explain any one method for measurement of high resistance.

Describe the constructional detail of a moving iron instrument with the help of diagram. Derive the equation for defection if spring control is used.

Write a short note on Systematic errors.

How the current range of PMMC instrument extended with the help of shunts?

Explain working of Kelvin’s double bridge for measurement of low resistance with neat diagram.

Draw circuit diagram of Schering bridge.

Explain construction of single phase induction type energy meter.

Explain measurement of unknown inductance with the help of Hay’s bridge. Also draw phasor diagram.

What do you mean by piezoresistive effect? State types of strain gauges.

State the advantages and applications of D.S.O.

Explain construction and working principle of Megger.1

Explain Clamp on meter.

Describe the different criteria for selection of transducers for a particular application.

Explain the construction and working principle of LVDT with neat sketch. Explain how the magnitude and direction of the displacement of core of LVDT can be detected.