Helper Electrician 

Duration – 75 Days Per Day – 2 Hours

SR.NO 

SYLLABUS

1

Elementary Concepts: Prerequisite: Concept of Potential difference. Current and resistance. Ohm’s law,  effect of temperature on resistance, resistance temperature coefficient, insulation resistance. SI units of  work Power and Energy. Conversion of energy from one form to another in electrical and thermal  systems. 

2

D. C. Circuits (Only Independent sources) Kirchhoff’s law, ideal and practical voltage and current  sources. Mesh and Nodal analysis (Super node and super Mesh excluded). Source transformation. Star  delta transformation. Superposition theorem, Thevevnins’s theorem Norton’s theorem, maximum  power transfer theorem (Source transformation not allowed for superposition theorem, Mesh and  Nodal analysis. 

3

A.C. Fundamentals: Sinusoidal voltage and currents, their mathematical and graphical representation,  concept of cycle period, frequency, instantaneous, peak, average, r.m.s. values, peak factor , and form  factor, phase difference, lagging, leading and in phase quantities and phasor representation. Rectangular  and polar representation of phasors. 

4

Study of A.C circuits of pure resistance, inductance and capacitance and corresponding voltage- current  phasor diagrams, voltage – current and power waveforms. 

5

Single phase AC Circuits: Study of series and parallel R-L, R-C, R-L-C circuits, concept of impedance and  admittance for different combinations, wave form and relevant voltage current phasor diagrams.  Concept of active, reactive, apparent, complex power and power factor, resonance in series and parallel  RLC circuit. Q- factor and band with 

6

Polyphase AC circuits: Concept of three phase supply and phase sequence. Balanced and unbalanced  loads voltage current and power relations in three phase balance star and delta loads and their phasor  diagrams. 

7

Electromagnetism:  

A) Magnetic effect of electrical current cross and dot convention, right hand thumb rule and cork screw  rule, nature of magnetic field of long straight conductor, concepts of solenoid and torrid. Concepts of  m.m.f, flux, flux density, reluctance, permeability and field strength, their units and relationship. Simple  series and parallel magnetic circuits. , comparison between electrical and magnetic circuits , force on  current carrying conductor placed in magnetic field, Fleming’s left hand rule.  

B) Faraday’s law of electromagnetic induction, Fleming’s right hand rule, statically and dynamically  induced EMF’s self and mutual inductance coefficient of coupling, energy stored in magnetic field C) Introduction to electrical AC DC Machines: Principles of operation and applications. 

8

Single phase transformer and electrostatics:  

A) Single phase transformers: Construction, principle of working, e.m.f equations, voltage and current  ratios, losses, definition of regulation and efficiency, determination of these by direct loading method.  Descriptive treatment of autotransformer.  

B) B) Electrostatics: electrostatic field, electric flux density, electric field strength, absolute permittivity,  relative permittivity and capacitance, composite dielectric capacitors, capacitors in series and parallel,  energy stored in capacitors, charging and discharging of capacitors and concept of time constant. 

9

Wiring exercises:  

i. study of wiring components( Wires, Switches, Fuses, sockets, plug, lamps and lamp holders,  rating of different accessories) 

ii. Control of two lamps from two switches ( looping system)  

iii. Stair case wiring  

iv. Use of megger for insulation testing and continuity test of wiring installation and machines

10

Study of fluorescent tube circuit 

ii. Study of compact Fluorescent lamps ( CFL) and Light Emitting Diode( LED) lamps iii. Study of sodium and mercury vapour lamps

11

Study of safety precautions while working on electrical installations and necessity of earthing  ii. Introduction to energy conservation 

iii. Study of single line diagram of power system