Skip to content
Padhora
Sign in
BrowsePlans

DI04009031 · Semester 4 · 5G scheme

Commissioning & Maintenance of Electrical Equipments

Notes and solutions following the Gujarat Technological University (GTU) syllabus for DI04009031. Independent material — not issued by the university.

Electrical Engineering

Materials

Syllabus

The official syllabus this material follows.

  • Syllabus

    8 pages

    FreeRead

Complete Book

The whole syllabus, unit by unit, written for the exam.

Slides

Lecture slides for revision.

Past Papers

Original question papers from previous exams.

  • Summer 2026 question paper

    3 pages

    FreeRead

PYQ Solutions

Past university papers, fully solved.

Syllabus units

Unit 1: Electrical Safety and Insulating Material
  • Do's and Don'ts Regarding Safety in Substation/ Power Station Operators.
  • Electrical Safety in Industry/Power Stations/ Substations at the Time of Operation/ Control/ Maintenance.
  • Factors Affecting Life of Insulating Materials, Classifications of Insulating Materials as Per Indian Standards.
  • Measuring Insulation Resistance by Different Methods Such As I) Polarization, Ii) Dielectric Absorption, Iii) Megger.
  • Reconditioning of Insulation-Drying Out Procedures.
  • Insulating Oil - Properties of Insulating Oil, Causes of Deterioration of Oil.
Unit 2: Installation and Maintenance of Electrical Equipment
  • Requirements of Foundation for Static and Rotating Electrical Machinery.
  • Concept of Levelling and Aligning- Procedure for Levelling and Aligning, Alignment of Direct Coupled Drive, Effects of Mis-Alignment.
  • Installation Procedure of Power Transformer as Per I.S.
  • Installation Procedure of Rotating Electrical Machine (Induction Motor and Alternators) as Per I.S.
  • Installation Procedure of Switchgear (Circuit Breaker, Isolator and Control Panel) as Per I.S.
  • Devices and Tools Required for Installation of Electrical Equipment.
  • Concept of Maintenance, Types of Maintenance, Routine, Preventive and Breakdown Maintenance.
  • Preventive Maintenance-Procedure for Developing Maintenance Schedules for Electrical Machines.
  • Factors Affecting Preventive Maintenance Schedules.
  • Maintenance Schedules of Following as Per IS: Power Transformer, Three Phase Induction Motor, Alternator, Circuit Breaker, Batteries, Solar and Wind Power Plants.
Unit 3: Commissioning of Transformer
  • Importance of Commissioning of Transformer.
  • Difference Between Type Test, Routine Test and Special Test.
  • Pre-Commissioning Checks- Significance, Procedure and Standard Reference Values for Pre- Commissioning Tests:
  • Insulation Resistance Measurement [Control Wiring, Cooling System Motor and Control Circuit, Main Windings (Polarization Index), Tap Changer Motor and Control]
  • Transformer Oil Break Down Voltage Test ( BDV) and Oil Filtering.
  • Polarity and Vector Group Test.
  • Ratio Test on All Taps.
  • Magnetizing Current Test.
  • Magnetic Balance Test. (For 3 Phase Transformer).
  • Capacitance and Tan Delta Measurement of Winding and Bushing.
  • Short Circuit Impedance Test.
  • Contact Resistance Measurement.
  • Measurement of Windings Resistance for all Taps of OLTC.
  • Final Commissioning Checks.
  • Procedure-Energization of Transformer.
  • Faults and Troubleshooting of Transformer and its Auxiliary Equipment.
Unit 4: Commissioning of Rotating Machines (Synchronous Machine, Induction Motor, DC Machine)
  • Pre-Commissioning Inspection Checks for Rotating Machines.
  • Pre-Start Tests on Rotating Machines-
  • Winding Resistance Measurement
  • Insulation Resistance Measurement of Windings
  • High Voltage Tests (Power Frequency)
  • Trial Start
  • No Load Test
  • Vibration Measurement
  • Faults and Troubleshooting of Rotating Machines (Synchronous Machine, Induction Motor, DC Machine).
Unit 5: Commissioning of Switchgear and Power Cable
  • Pre-Commissioning Checks of Switchgear
  • Visual Inspection (Nameplate, Interlocks).
  • Insulation Resistance (IR) Measurement.
  • Contact Resistance Test of Circuit Breakers and Isolators.
  • CTs, PTs, And Protection Relay Connections Verification.
  • Functional Tests of Switchgear
  • Mechanical Operation Test.
  • Protection Relay and Control Circuit Testing.
  • Interlock Verification (Electrical & Mechanical).
  • SF₆ Gas / Vacuum Integrity Test.
  • On-Site Commissioning Tests of Switchgear
  • High-Voltage Withstand Test. (As Per IS/IEC).
  • Partial Discharge Test (For GIS).
  • Breaker Timing Test
  • Pre-Commissioning Checks of Power Cable
  • Physical Inspection (Joints, Terminations, Bending Radius).
  • Conductor Resistance & Continuity Test.
  • Insulation Resistance Measurement (Megger Test).
  • Site Acceptance Tests of Power Cable
  • High-Voltage Withstand Test.
  • Sheath Integrity Test.
  • Capacitance and Tan ⸹(Dissipation Factor) Measurement.
  • Post-commissioning
  • Load Test Under Service Conditions.
  • Temperature Monitoring During Initial Energization.
  • Documentation of Test Results.
  • Faults and Troubleshooting of Switchgear and Power Cable.

About this course

Electrical systems in power generation, industrial, and commercial facilities include a wide range of equipment and devices such as transformers, motors, circuit breakers, and other machinery operating at different stages and often situated close to one another. These components must be properly installed, commissioned, and maintained on a regular basis to avoid major failures. Diploma-level engineers are frequently responsible for overseeing or performing these tasks in power plants, substations, and industrial environments. This course is designed to equip students with a thorough understanding of the correct procedures for installation, commissioning, and maintenance of electrical equipment. It also emphasizes key concepts and principles, while providing hands-on experience to develop practical skills necessary for working with electrical systems in real-world settings.