RRB Technician Electrical Syllabus

The RRB Technician Electrical CBT 2 discipline section tests technical knowledge at the ITI and Diploma level across all major topic areas of the Electrical trade. It carries 100 questions and 100 marks within the 150-question CBT 2 paper. The CBT 2 score is the sole basis for the final Technician merit list.

Quick Facts: Technician Electrical

Detailed Electrical Syllabus

Questions in the Electrical section test trade theory, applied calculations, materials knowledge, tools and equipment, process steps, quality standards, and safety regulations at the NCVT ITI level. The following topic clusters are covered:

1. Electrical Fundamentals and Circuit Theory

•        Ohm's Law; series and parallel circuits; Kirchhoff's Current Law (KCL) and Kirchhoff's Voltage Law (KVL); Thevenin's and Norton's theorems; Superposition theorem; Maximum Power Transfer theorem

•        Electromagnetism: magnetic field; flux; flux density; permeability; MMF; reluctance; magnetic circuits; Faraday's Laws of Electromagnetic Induction; Lenz's Law; self-inductance; mutual inductance; energy stored in magnetic field

•        AC Fundamentals: sinusoidal EMF generation; frequency; period; amplitude; phase; RMS and average values; form factor; peak factor; phasor representation

•        AC Circuits: purely R, L, C circuits; series RL, RC, RLC; impedance; admittance; power factor; active, reactive, and apparent power; resonance (series and parallel); Q-factor; bandwidth

•        Three-Phase Systems: advantages; star and delta connections; line and phase voltages and currents; balanced and unbalanced loads; three-phase power; two-wattmeter method; power factor correction using capacitor bank

•        Capacitance: types of capacitors; capacitors in series and parallel; energy stored; charging and discharging; time constant (tau = RC)

2. Electrical Machines

•        DC Generator: construction (armature, field winding, commutator, brushes, yoke); EMF equation E = PphiNZ / 60A; types (shunt, series, compound -- short and long shunt); armature reaction; commutation; losses (copper, iron, stray); efficiency; characteristics (OCC, load characteristics)

•        DC Motor: back EMF; torque equation T = PphiIa Z / 2 pi A; types (shunt, series, compound); starting (3-point and 4-point starters); speed control (armature resistance, field weakening, Ward-Leonard); braking (regenerative, dynamic, plugging); testing (Swinburne, Hopkinson)

•        Transformer: construction (core type, shell type); EMF equation E = 4.44 f phi N; turns ratio; ideal transformer; practical transformer equivalent circuit; phasor diagram; voltage regulation; efficiency; losses (hysteresis and eddy current -- iron; copper -- I^2R); cooling methods; auto-transformer; three-phase transformer (star-delta, delta-star connections, vector groups); tap-changing; parallel operation conditions

•        Three-Phase Induction Motor: rotating magnetic field; synchronous speed Ns = 120f/P; slip s = (Ns-N)/Ns; equivalent circuit; torque equation; starting torque; full load torque; maximum torque; torque-speed characteristics; starting methods (DOL, star-delta, auto-transformer, rotor resistance); speed control (stator voltage variation, VFD/VVVF, rotor resistance); power stages; losses and efficiency; testing (no-load, blocked rotor); applications

•        Single-Phase Induction Motor: double revolving field theory; capacitor start; capacitor run; shaded pole; split phase; repulsion type; speed control; applications

•        Synchronous Machine: construction; EMF equation; synchronous speed; armature reaction (unity, lagging, leading pf); synchronous reactance; equivalent circuit; phasor diagram; voltage regulation (EMF, MMF, ZPF, ASA methods); power angle; torque; synchronous motor V-curves; hunting; parallel operation; synchronous motor starting methods

3. Power Systems

•        Transmission Lines: types (HVAC, HVDC); line constants (R, L, C, G); short (lumped), medium (T and pi model), and long (distributed) line models; ABCD parameters; regulation; efficiency; Ferranti effect; corona (causes, conditions, advantages and disadvantages, methods to reduce); skin effect

•        Distribution: types (radial, ring, interconnected); secondary distribution; voltage drop in feeder; design of distributors (single-end and double-end fed)

•        Protective Relays: principle; types (over-current relay -- IDMT, BO; distance relay; differential relay; Buchholz relay for transformer; earth fault relay); relay co-ordination; current transformer (CT) and potential transformer (PT) -- accuracy class; burden; connection

•        Circuit Breakers: arc interruption theory; types (air break -- ACB, MCCB, MCB; oil -- BOCB, MOCB; SF6; vacuum); ratings (rated voltage, current, breaking capacity, making capacity); selection; testing

•        Power System Protection: protection zones; unit protection; bus bar protection; generator protection; transformer protection; feeder protection; motor protection; distance relay settings

•        Earthing: types (plate, pipe, strip, ring); IS 3043; earth resistance (measurement -- fall-of-potential method, ratio method; acceptable values); neutral earthing (solid, resistance, reactance, resonant earthing)

4. Electrical Wiring, Installation and Maintenance

•        Wiring Systems: cleat, casing-capping, CTS/TRS, conduit (surface and concealed) wiring; IE Rules 1956/2020; NBC 2016 provisions for electrical installations

•        Cables: types (PVC -- IS 694; XLPE -- IS 7098; armoured; fire retardant FRLSH); selection (current rating, voltage drop, type of installation); cable laying; jointing; terminations; lugs and glands

•        Switchgear: fuses (IS 2208; IS 13703); MCBs (tripping characteristics B, C, D; Ics and Icu); RCCBs and ELCBs (30 mA for personal protection; testing); MCCBs (adjustable trip); contactors; starters (DOL, star-delta)

•        Illumination: luminous flux (lumen); illuminance (lux); luminance (cd/m^2); laws (inverse square; Lambert's cosine); efficacy; CRI; CCT; lamp types (incandescent; fluorescent T8/T5; CFL; LED; HPSV; HPMV; metal halide); lighting design by lumen method; IS 3646

•        Battery Systems: lead-acid (construction; chemical action; Ah capacity; charging methods -- constant current, constant voltage, trickle; testing -- hydrometer, load test; maintenance; capacity vs temperature); alkaline batteries; VRLA; UPS (online, offline, line-interactive); battery room safety

•        Maintenance: types (preventive, predictive, corrective, condition-based); insulation resistance testing (megger test; acceptable IR values; polarisation index PI = IR at 10 min / IR at 1 min; >4 is excellent); motor maintenance (vibration; bearing temperature; winding resistance; dynamic balance); transformer maintenance (oil level; oil BDV; DGA; silica gel breather; Buchholz relay testing)

5. Power Electronics and Drives

•        Semiconductor Devices: SCR (thyristor) -- construction, V-I characteristics, triggering (gate, light, heat, dv/dt), latching and holding current, commutation; TRIAC; DIAC; GTO; IGBT; MOSFET -- characteristics and applications in power electronics

•        Rectifiers: uncontrolled (single-phase half-wave, full-wave centre-tap, bridge; three-phase half-wave, full-wave); controlled (single-phase and three-phase SCR rectifiers); ripple factor; performance parameters; filter circuits

•        Inverters: single-phase and three-phase voltage source inverters; current source inverters; PWM (sinusoidal PWM, space vector PWM); output voltage and frequency control; applications

•        Choppers: type A (step-down/buck); type B (step-up/boost); type C (two-quadrant); type D and E (four-quadrant); duty cycle; DC motor speed control using chopper; applications in battery chargers and DC drives

•        AC Voltage Controllers: single-phase on-off control; phase angle control; TRIAC-based controllers; applications (light dimmer, fan speed control)

•        VFD (Variable Frequency Drive): V/f control principle; closed-loop vector control; types (6-pulse, 12-pulse, 18-pulse); harmonic distortion; power factor; EMC filters; applications in pump, fan, compressor, and locomotive traction drives

6. Measurement and Instrumentation

•        Electrical Measurement: PMMC; moving iron; dynamometer; rectifier instruments -- working, accuracy, errors

•        Power Measurement: wattmeter connection (LPF wattmeter; UPF wattmeter); two-wattmeter method for three-phase power; energy meter (induction type; LCD/digital energy meter); power factor meter; frequency meter; harmonic analyser

•        Resistance Measurement: ammeter-voltmeter method; Wheatstone bridge (medium resistance); Kelvin double bridge (low resistance); earth resistance measurement (fall-of-potential; ratio method; clamp-on earth tester)

•        Capacitance and Inductance Measurement: Schering bridge (C); Maxwell bridge (L); Hay bridge (L with Q>10); Anderson bridge (L); using LCR meter

•        Insulation Resistance: megger (500V, 1000V, 2500V, 5000V types); polarisation index; dielectric absorption ratio; step voltage test; acceptable IR values for motors, cables, and transformers

•        Transducers: thermocouple (types J, K, T, E; cold junction compensation); RTD (Pt100, 2-wire, 3-wire, 4-wire); thermistor; strain gauge; LVDT; pressure transducer; flow transducer (CT based on electromagnetic, turbine, ultrasonic)

•        Oscilloscope: CRT working; Lissajous figures; measurement of voltage, frequency, phase angle; digital oscilloscope; bandwidth; sampling rate

7. Railway Electrical Systems

•        Electric Traction: systems in India (25 kV AC 50 Hz single-phase overhead -- most common on Indian Railways; 1500 V DC; 750 V DC third rail -- Chennai Metro); advantages of electric traction over diesel (no local emissions, higher acceleration, regenerative braking, lower operating cost)

•        Traction Power Supply: grid power at 220 kV or 132 kV; traction substation (TSS) -- AT (Auto-Transformer) feeding arrangement; BT (Booster Transformer) feeding; switching and sectioning post; neutral section; protection of 25 kV OHE

•        Overhead Equipment (OHE): catenary wire (contact wire + messenger wire + dropper); stagger (210 mm or 200 mm on curves); contact wire height (5.5 m to 5.8 m); OHE components (mast, boom, stagger, registration arm, section insulator, auto-tensioning device)

•        Electric Locomotive: pantograph; main transformer (on-board); converter (4-quadrant, IGBT-based); traction motors (3-phase induction motors on WAP-5, WAP-7; DC series on older locos); regenerative braking; WAP-4, WAP-5, WAP-7, WAG-9 -- specifications

•        Station Electrical: HT supply (33/11 kV); LT distribution; lighting circuits; platform lighting; escalator and lift power; CCTV; public address power; railway station solar power systems

•        Energy Efficiency: ISO 50001 in Indian Railways; head-end power (HEP) for coaches; OBHS (On-Board Housekeeping System); regenerative braking energy recovery; LED lighting at stations

Common Technical Section (50 Questions)

In addition to the 100-mark trade section, all Technician candidates must answer the following 50-mark common section in CBT 2:

Physics and Chemistry (20 Questions -- Class 12 / Diploma Level)

•        Physics (Class 12 / Diploma Level): Units and Measurement; Motion (kinematics; Newton's Laws); Work, Energy and Power; Properties of Matter (elasticity, viscosity, surface tension); Heat and Thermodynamics (specific heat, latent heat, laws of thermodynamics, Carnot cycle); Sound (wave motion, Doppler effect, resonance); Light (laws of reflection and refraction; lenses and mirrors; Young's double slit; diffraction; polarisation); Electrostatics (Coulomb's Law, capacitance, dielectrics); Current Electricity (Ohm's Law, Kirchhoff's Laws, Wheatstone bridge, power); Magnetic Effects of Current (Biot-Savart, Ampere's Law, force on conductor); Electromagnetic Induction (Faraday and Lenz); AC Circuits (RMS, LCR, resonance, power factor); Semiconductor Devices (p-n junction, transistor basics, logic gates); Modern Physics (photoelectric effect, radioactivity, nuclear reactions)

•        Chemistry (Class 12 / Diploma Level): Atomic Structure (Bohr model, quantum numbers, electronic configuration); Periodic Table (periodicity, s, p, d, f blocks, periodic trends); Chemical Bonding (ionic, covalent, metallic, VSEPR, hybridisation); States of Matter (gas laws -- Boyle's, Charles's, Avogadro's; ideal and real gases); Thermodynamics (enthalpy, Hess's Law, entropy, Gibbs free energy); Chemical Equilibrium (Le Chatelier's principle, Kp, Kc); Electrochemistry (electrode potential, Nernst equation, electrolysis, Faraday's Laws, corrosion); Chemical Kinetics (rate law, order, activation energy, Arrhenius equation); p-Block Elements (Groups 15 to 18 -- properties, compounds, oxoacids); d-Block Elements (transition metals, oxidation states, colour); Organic Chemistry (reactions SN1, SN2, E1, E2; IUPAC nomenclature; functional groups; biomolecules); Polymers and Chemistry in Everyday Life

Basics of Computer Applications (15 Questions)

•        Computer Applications Basics (Class 10 / ITI Level): Computer components (CPU, RAM, ROM, storage -- HDD, SSD; I/O devices; ports); Operating system functions; MS Office (Word -- formatting, tables, find-replace; Excel -- formulae SUM, AVERAGE, IF, VLOOKUP, charts; PowerPoint -- slides, transitions); Internet (browser, search engine, URL, HTTP, HTTPS, email, online safety); File management (folders, file types, copy, move, delete, zip); Network basics (LAN, WAN, Wi-Fi, IP address, router, modem); Cybersecurity (password best practices, phishing, antivirus, firewalls); Binary, octal, hexadecimal number systems and conversion; Logic gates (AND, OR, NOT, NAND, NOR, XOR) -- truth tables and Boolean expressions

Environment and Pollution Control (15 Questions)

•        Environmental and Pollution Control (Class 10 / ITI Level): Types of pollution -- Air (pollutants: PM2.5, PM10, SOx, NOx, CO, VOCs; sources; health effects; vehicular emission norms BS6; AQI); Water (BOD, COD, DO; sources of water pollution; effects; treatment methods -- primary, secondary, tertiary); Soil (pesticides, heavy metals, plastic; remediation); Noise (dB scale; CPCB limits; control measures); Solid Waste Management (classification; 3R principle; composting; sanitary landfill; e-waste; plastic waste rules; biomedical waste); Renewable Energy (solar PV and thermal; wind; hydro; biomass; geothermal; hydrogen; India's renewable targets); Climate Change (greenhouse gases; global warming; Paris Agreement; India's NDC); Environmental Legislation (EPA 1986; Air Act 1981; Water Act 1974; Forest Conservation Act; Wildlife Protection Act; National Green Tribunal); Indian Railways Green Initiatives (bio-toilets; solar energy on trains and stations; LED lighting; rainwater harvesting; ISO 14001; plastic-free stations)

Preparation Strategy

1. NCVT ITI Electrical Trade Theory is the Primary Source

The NCVT-prescribed ITI textbooks for the Electrical trade (published by DGT or state ITI boards) are the most accurate and exam-aligned source. Read every chapter systematically, noting definitions, formulae, IS codes, process steps, safety rules, and tool specifications.

2. Focus on Factual, Numerical, and Standards-Based Content

MCQs in the trade section frequently test specific technical values, IS code provisions, standard formulations, and process parameters. Memorise standard values (voltage levels, wire gauges, material properties, temperature limits, safety clearances) for reliable marks.

3. Practise from SSC JE and RRB Technician Question Banks

Solve previous years' RRB Technician and SSC JE Electrical question banks for difficulty calibration and exposure to typical question formats. Previous paper analysis reveals the most frequently tested topics.

Frequently Asked Questions

Q1. Is the Electrical Technician syllabus the same as the JE Electrical syllabus?

The topics overlap but the Technician paper is at ITI level while the JE paper is at Diploma/Degree level. JE questions are more analytical and deeper; Technician questions are more applied and practical at the trade level.

Q2. Are IS codes tested in the Technician trade section?

Yes. Questions on relevant IS codes, safety standards, and BIS specifications for the trade appear regularly. Prepare a list of key IS codes applicable to your trade.