Exam: PGCIL Diploma Trainee (Electrical) | Date: 11th April 2025 | Total Questions: 120 | Topics: 17

Power Grid Corporation of India Limited (PGCIL) conducted the Diploma Trainee (Electrical) exam on 11th April 2025. The paper comprised 120 questions spread across 17 major Electrical Engineering topics and 108 subtopics. This article provides a complete subject-wise and topic-wise question distribution to help future aspirants understand the exam pattern and plan their preparation effectively.

Exam Overview

Particulars	Details
Organisation	Power Grid Corporation of India Limited (PGCIL)
Post	Diploma Trainee (Electrical)
Exam Date	11th April 2025
Section	Electrical Engineering
Total Questions	120
Total Topics Covered	17
Total Subtopics	108

Topic-Wise Question Distribution

Topic	No. of Questions
Power Transmission	15
Measurements & Instrumentation	12
Network Theory	10
Induction Motors	10
AC Circuits	9
Electromagnetic Theory	9
Power Distribution	8
Control Systems	7
Estimation & Costing	7
Electronics / Semiconductors	6
Three-Phase Systems	5
Special Motors & Drives	5
Power Plants	4
Illumination	4
DC Machines	3
Operational Amplifiers	3
Welding	3
Total	120

Highest weightage topics: Power Transmission (15 Qs), Measurements & Instrumentation (12 Qs), Network Theory (10 Qs), and Induction Motors (10 Qs) together account for 47 out of 120 questions — nearly 40% of the paper.

Detailed Topic & Subtopic Analysis

1. Power Transmission (15 Questions)

The highest-weightage topic in the exam. Covers transmission line parameters, HVDC/EHVAC systems, and corona-related concepts.

Subtopic	Questions Asked
Graded Insulators / String Efficiency	1
HVDC Features	1
Conductor Sag	1
High-Voltage Transmission Purpose	1
Power Loss and Line Length	1
Charging Current	1
Corona Effect Factors	1
EHVAC Advantage	2
Higher Voltage Transmission (A&R)	1
Capacitance Per Unit Length	1
Skin Effect	1
Tower Type for 400 kV	1
Aluminium vs Copper Conductors	1
Bundled Conductors / Corona Minimisation	1

2. Measurements & Instrumentation (12 Questions)

Second highest in weightage. Covers energy meters, bridges, instrument types, and measurement errors.

Subtopic	Questions Asked
Energy Meter Tests	1
PMMC Temperature Error	1
MI Instruments	1
Average Demand Calculation	1
Drift in Instruments	1
Wattmeter Errors	1
Classification of Instruments (Output Format)	1
Active vs Passive Instruments	1
Electrodynamic Instrument Deflecting Torque	1
Energy Meter Adjustment	1
Anderson's Bridge Limitations	1
Potential Transformer Components	1

3. Network Theory (10 Questions)

Core circuit analysis topic. Thevenin's theorem and Star-Delta conversion had the most repeated subtopics.

Subtopic	Questions Asked
Transfer Functions	1
Thevenin / Max Power Transfer	3
Basic Power Calculation	1
Star ↔ Delta Conversion	2
Source Transformation	1
Laplace Transforms	1
Capacitor Properties	1

4. Induction Motors (10 Questions)

Equal weight to Network Theory. Covers motor starting, torque characteristics, and speed control methods.

Subtopic	Questions Asked
Laminated Core Purpose	1
Torque at High Speed	1
AC Series Motor Load Effect	1
Star-Delta Starter	1
No-Load Test	1
Slip Ring Motor External Resistance	1
Rotor Torque Mechanism	1
Four-Quadrant Operation	1
Full Load to Max Torque Ratio	1
Stator Side Speed Control	1

5. AC Circuits (9 Questions)

Covers RLC circuit behaviour, resonance, power triangle, and reactance concepts.

Subtopic	Questions Asked
Capacitor Phase Relationship	1
Reactive Power (Resistive Load)	1
Power Triangle	1
Series RLC - Quality Factor	1
Parallel RLC at Resonance	1
Series RLC - Voltage Magnification	1
Phase Difference in Series RLC	1
Current at Resonance	1
Inductive Reactance vs Frequency	1

6. Electromagnetic Theory (9 Questions)

Covers magnetic circuits, field laws, and material properties.

Subtopic	Questions Asked
MMF & Units	2
Relative Permeability	1
Laplace's Law / Magnetic Field Lines	1
Fleming's Left-Hand Rule	1
Hard & Soft Magnets	1
Work Law in Magnetic Circuit	1
MMF in Magnetic Circuit	1
Reluctance & Permeability	1

7. Power Distribution (8 Questions)

Covers distribution networks, substations, FACTS controllers, and grid feeders.

Subtopic	Questions Asked
Substation Site Selection	1
Voltage Drop Factors	1
Secondary Distribution Lines	1
National Grid	1
Single Line Diagram Symbol	1
Grid Distribution Feeder Failure	1
FACTS Controllers (Shunt)	1
Rural Distribution Substations	1

8. Control Systems (7 Questions)

Covers open-loop and closed-loop systems, PID controllers, and system response characteristics.

Subtopic	Questions Asked
Open-Loop System Non-linearity	1
Peak Time of Second-Order System	1
Underdamped System Oscillatory Behaviour	1
PID Controller	1
Summing Junction	1
Feedback Type in Closed-Loop	1
LTI System Characteristics	1

9. Estimation & Costing (7 Questions)

Covers billing, cost estimation methods, transformer rating, and detailed estimates.

Subtopic	Questions Asked
Measurement Book in Billing	1
Cost Estimation for Public Lighting	1
Distribution Transformer Rating Factor	1
Order Format Components	1
Transformer Cost Factor	1
Costing Method for Large Projects	1
Detailed Estimate Components	1

10. Electronics / Semiconductors (6 Questions)

Covers semiconductor devices, FETs, rectifiers, and energy band theory.

Subtopic	Questions Asked
Built-in Potential in p-n Junction	1
JFET Type	1
Enhancement MOSFET at VGS=0	1
Half-Wave Rectifier RMS	1
Common-Source FET Amplifier	1
Energy Band at Absolute Zero	1

11. Three-Phase Systems (5 Questions)

Covers power calculations, star connections, and balanced/unbalanced systems.

Subtopic	Questions Asked
Reactive Power Distribution	1
Apparent vs True Power at Unity PF	1
Balanced / Unbalanced Star Systems	1
Three-Phase Power Formula	1
Star Connection Line Voltage	1

12. Special Motors & Drives (5 Questions)

Covers PMSM, universal motors, electric braking, and drive comparisons.

Subtopic	Questions Asked
Electric Braking in Elevator Motors	1
Signalling Devices Motor Type	1
Three-Phase vs Single-Phase Drives	1
Universal Motor	1
PMSM Rotor	1

13. Power Plants (4 Questions)

Covers hydro, nuclear, and thermal plant concepts.

Subtopic	Questions Asked
Francis Turbine Spiral Casing	1
Hydroelectric Plant Efficiency	1
Spinning Reserve	1
U-235 Fission Energy	1

14. Illumination (4 Questions)

Covers lighting design, luminous flux, and outdoor lighting classification.

Subtopic	Questions Asked
Luminous Flux vs Radiant Flux	1
Space-Height Ratio	1
Classification of Outdoor Lighting	1
Lighting Pole Placement	1

15. DC Machines (3 Questions)

Covers torque, EMF generation, and motor testing.

Subtopic	Questions Asked
Shaft vs Armature Torque	1
Factors Affecting Generated EMF	1
Brake Test of DC Motor	1

16. Operational Amplifiers (3 Questions)

Covers op-amp configurations, slew rate, and equivalent models.

Subtopic	Questions Asked
Inverting Summing Amplifier	1
Slew Rate	1
Op-Amp Electrical Equivalent Model	1

17. Welding (3 Questions)

Covers welding types, joint quality, and DC vs AC welding.

Subtopic	Questions Asked
Good Weld Under Stress	1
Butt Welding Advantages	1
DC vs AC Welding	1

Key Takeaways for PGCIL Diploma Trainee (Electrical) Aspirants

Power Transmission is the most critical topic — 15 questions covering HVDC, Corona, Skin Effect, Sag, and Bundled Conductors. Do not skip any subtopic here.
Measurements & Instrumentation deserves dedicated preparation — 12 questions on energy meters, bridges, instrument errors, and PT components.
Network Theory and Induction Motors (10 Qs each) are equally important — master Thevenin's theorem, Star-Delta, motor torque, and starting methods.
AC Circuits and Electromagnetic Theory (9 Qs each) — focus on RLC resonance, power triangle, magnetic circuits, and MMF.
Lower-weightage topics like Welding, DC Machines, and Op-Amps (3 Qs each) should not be ignored — they are easy scoring opportunities.

Preparation tip: Focus your first revision round on the top 6 topics (Power Transmission, M&I, Network Theory, Induction Motors, AC Circuits, Electromagnetic Theory) — they together contribute 65 out of 120 questions, which is over 54% of the total paper.

Frequently Asked Questions (FAQs)

Q1. Which subject has the highest weightage in PGCIL Diploma Trainee (Electrical) exam?

Power Transmission has the highest weightage with 15 questions, followed by Measurements & Instrumentation with 12 questions. Together they account for 27 out of 120 questions.

Q2. How many topics and subtopics were covered in the PGCIL Diploma Trainee Electrical exam on 11th April 2025?

The exam covered 17 major topics and 108 subtopics across 120 questions in the Electrical Engineering section.

Q3. Are lower-weightage topics like Welding and Illumination asked in PGCIL Diploma Trainee exam?

Yes — Welding (3 Qs), Illumination (4 Qs), and DC Machines (3 Qs) were all present in the 11th April 2025 paper. While they carry fewer questions, they are relatively straightforward and should not be skipped.