D C circuits: Ohm’s Law and Kirchhoff’s Laws, analysis of series, parallel and seriesparallelcircuits excited by independent voltage sources. Power and Energy. Illustrativeexamples. Electromagnetism:
Review of field around a conductor and coil, magnetic flux and flux density, magnetomotiveforce and magnetic field intensity, reluctance and permeability, definition of magneticcircuit and basic analogy between electric and magnetic circuits. (These topics are not to beconsidered for setting the examination questions).
Electromagnetic induction:
Definition of Electromagnetic Induction, Faradays Laws,Fleming’s right hand rule, Lenz’s Law, Statically and dynamically induced emf. Selfinductance,mutual inductance and coefficient of coupling. Energy stored in magneticfield. Illustrative examples. Force on current carrying conductor placed in a magnetic field,Fleming’s left hand rule.
DC Machines: Working principle of DC machine as a generator and a motor. Typesand constructional features. Types of armature windings, Emf equation of generator,relation between induced emf and terminal voltage with a mention of brush contact dropand drop due to armature reaction. Illustrative examples, neglecting armature reaction.
Operation of DC motor, back emf, torque equation. Types of DC motors, characteristics andapplications. Significance of back emf. Necessity of a starter for DC motor. Illustrativeexamples on back emf and torque.
Measuring Instruments: Construction and Principle of operation of dynamometer typewattmeterand single phase induction type energy meter.
Single-phase AC circuits: Generation of sinusoidal voltage, frequency of generated voltage,definition and numerical values of average value, root mean square value, form factorand peak factor of sinusoidally varying quantities, phasor representation of alternatingquantities. Analysis, with phasor diagrams, of R, L, C, R-L, R-C and R-L-C circuits and,parallel and series- parallel circuits. Real power, reactive power, apparent power and powerfactor. Illustrative examples.
Domestic wiring:
Service mains, meter board and distribution board. Brief discussion on concealed conduitwiring. Two-way and three-way control. Elementary discussion on Circuit protectivedevices: fuse and Miniature Circuit Breaker (MCB’s). Electric shock, precautions againstshock, Objectives of Earthing, types of earthing; pipe and plate earthing, Residual currentcircuit breaker (RCCB).
Three Phase Circuits: Necessity and advantages of three phase systems, generation ofthree phase power. Definition of Phase sequence, balanced supply and balanced load.Relationship between line and phase values of balanced star and delta connections. Powerin balanced three-phase circuits, measurement of power by two-wattmeter method.Determination power factor using wattmeter readings. Illustrative examples.
Three PhaseSynchronous Generators: Principle of operation, Types and constructionalfeatures, Advantages of rotating field type alternator, Synchronous speed, Frequency ofgenerated voltage, Emf equation. Concept of winding factor (excluding the derivation ofdistribution and pitch factors). Illustrative examples on calculation of distribution factor,pitch factor and emf equation.
Single Phase Transformers:
Necessity of transformer, Principle of operation and construction of single-phasetransformers (core and shell types). Emf equation, losses, variation losses with respect toload, efficiency, Condition for maximum efficiency, Voltage regulation and its significance(Open Circuit and Short circuit tests, equivalent circuit and phasor diagrams are excluded).Illustrative problems on emf equation and efficiency only.
Three Phase Induction Motors: Principle of operation, Concept and production ofrotating magnetic field, Synchronous speed, rotor speed, Slip, Frequency of the rotorinduced emf, Types and Constructional features. Slip and its significance. Applications ofsquirrel - cage and slip - ring motors. Necessity of a starter, starting of motor using starsdeltastarter. Illustrative examples on slip calculations.