single-phase energy meter by phantom loading.

Unit-2

Polyphase Metering:

Blondel's Theorem for n-phase, p-wire system. Measurement of power

and reactive kVA in 3-phase balanced and unbalanced systems: One-wattmeter, two-wattmeter

and three-wattmeter methods. 3-phase induction type energy meter. Instrument Transformers:

Construction and operation of current and potential transformers. Ratio and phase angle errors

and their minimization. Effect of variation of power factor, secondary burden and frequency on

errors. Testing of CTs and PTs. Applications of CTs and PTs for the measurement of current,

voltage, power and energy.

Unit-3

Potentiometers:

Construction, operation and standardization of DC potentiometers– slide wire

and Crompton potentiometers. Use of potentiometer for measurement of resistance and

voltmeter and ammeter calibrations. Volt ratio boxes. Construction, operation and

standardization of AC potentiometer – in-phase and quadrature potentiometers. Applications

of AC potentiometers.

Unit-4

Measurement of Resistances:

Classification of resistance. Measurement of medium

resistances – ammeter and voltmeter method, substitution method, Wheatstone bridge method.

Measurement of low resistances – Potentiometer method and Kelvin's double bridge method.

Measurement of high resistance: Price's Guard-wire method. Measurement of earth resistance.

Unit-5

AC Bridges:

Generalized treatment of four-arm AC bridges. Sources and detectors. Maxwell's

bridge, Hay's bridge and Anderson bridge for self-inductance measurement. Heaviside's bridge

for mutual inductance measurement. De Sauty Bridge for capacitance measurement. Wien's

bridge for capacitance and frequency measurements. Sources of error in bridge measurements