Course Overview

  • 3 Hours

  • All Levels

  • All Devices

  • 12 Months Access

  • Handbook

  • Certificate


Electrical bushings are essential components for a wide range of electrical equipment such as power transformers, shunt reactors, circuit breakers, and capacitors. Despite presenting an outward impression of simplicity, bushings have evolved into complex components which perform the critical function of carrying current at high voltage through equipment enclosures and barriers. This course covers the basics of electrical bushings, their major types, construction, design requirements and condition assessment tests. 

You will learn:

  • The basic function of an electrical bushing.
  • Bushing applications and historical development. 
  • Main bushing types and their components. 
  • Solid/bulk type bushing design (porcelain, composite resin silicon and cast resin).
  • Basic concepts and construction of condenser bushings (capacitance graded bushings). 
  • Different condenser bushing technologies (RBP, OIP, RIP and RIS). 
  • Contemporary bushing standards and design requirements.
  • Different kinds of bushing connections (fixed, draw lead and draw rod).
  • What voltage and test taps on condenser bushings are.
  • Bushing condition and diagnostic tests (capacitance, Tanδ and partial discharges etc.).
  • And a lot more!

Interactive 3D models have been used to show you variuos bushing designs in great detail.

2D images have been used to clarify underlying concepts and theory. 

The course contains a PDF handbook.

Hope to see you on the course!


This is a non-video (NV) course. Please check for the associated video course if you prefer this method of learning.


Register to access free preview lessons.

  • 2
    Solid/Bulk Bushings
    • Solid/Bulk Type Bushings
    • Porcelain Bulk Bushings
    • Composite Resin Silicon (CRS) Bulk Bushings
    • Cast Resin Bushings
    • Limitations of Solid/Bulk Bushings
  • 3
    Capacitance-Graded / Condenser Bushings
    • Capacitance-Graded or Condenser Type Bushings
    • Basic Concept and Construction of a Condenser Bushing Core
    • Condenser Bushing Grading Technologies
    • Main Classifications of Capacitance-Graded/Condenser Type Bushings
    • Resin Bonded Paper (RBP) Bushings
    • Oil Impregnated Paper (OIP) Bushings
    • Resin Impregnated Paper (RIP) Bushings
    • Resin Impregnated Synthetic (RIS) Bushings
    • Capacitance-Graded Condenser Bushings Summary
  • 4
    International Standards
    • International Standards
    • Electrical Bushing Standards
  • 5
    Design Considerations
    • Design Considerations
  • 6
    Bushing Connections
    • Bushing Connections
  • 7
    Condition Assessment and Maintenance
    • Condition Assessment & Maintenance
    • Voltage and Test Taps
    • Bushing Diagnostic Tests
    • Visual Inspection
    • C1 and C2 Measurements
    • Tanδ (Dissipation factor)
    • Partial Discharge (PD)
    • Infrared (IR) Scanning / Thermal Vision
  • 8
    Final Thoughts
    • Final Thoughts
  • 9
    • Interactive 3D Models
    • Handbook
    • Bibliography