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EDWartens UK

Free course · Electrical

Testing and Maintenance of Transformers and Switchgear

Run, read and record the field tests that keep transformers, breakers, cables, motors and batteries in service: insulation resistance and PI, winding resistance, turns ratio and vector group, tan delta and SFRA, oil and DGA, breaker timing and contact resistance, switchgear thermography, VLF cable tests, motor tests, earth resistance and battery capacity, then turn the results into a maintenance plan.

See the modules

Free to learn. Verifiable certificate £19 when you pass the final exam (optional, VAT included).

Level
Intermediate
Modules
13
Video
26 hours
Price
Free

Outcome

What you will be able to do

Choose a maintenance strategy for each electrical asset and set intervals from P-F intervals and condition; run and interpret insulation resistance, DAR and PI tests with temperature correction; test transformer winding resistance, turns ratio, vector group and magnetising current; explain tan delta, capacitance and SFRA results; interpret oil breakdown voltage and DGA with Duval Triangle 1 and the IEC 60599 ratios; test circuit breaker contact resistance, timing, coil current, SF6 and vacuum integrity; maintain switchgear and MCCs with torque checks and thermography; test cables with insulation resistance, VLF and tan delta; test motors and look after bearings; measure earth resistance by fall of potential; maintain batteries and UPS; and turn test records into trends, work orders and an annual maintenance plan.

  • Choose a maintenance strategy for each asset and set test intervals from the P-F interval and condition
  • Run insulation resistance tests and calculate DAR and PI with temperature correction
  • Test winding resistance, turns ratio, vector group and excitation current on a transformer
  • Interpret tan delta, capacitance and SFRA results against their baselines
  • Interpret oil breakdown voltage and DGA with Duval Triangle 1 and the IEC 60599 ratios
  • Test circuit breaker contact resistance, timing, coil current, SF6 and vacuum integrity
  • Maintain switchgear and MCCs with torque checks and thermography, and test cables, motors, earthing and batteries
  • Turn test results into trends, prioritised work orders and an annual maintenance plan

Software

A spreadsheet (LibreOffice Calc is free) for test records, temperature corrections, Duval triangle percentages and trend lines. No test-set software is needed: every test is planned and its results worked on paper.

Hardware

None required. Access to an insulation tester, a micro-ohmmeter or a turns ratio tester at work or college makes the modules far more useful, but only under your site's safety rules and a permit to work.

Syllabus

13 modules

Each module has video lessons, notes and a short quiz. The final exam closes the course.

  1. 1Maintenance strategies: breakdown, preventive, predictive and RCM4 lessons
  2. 2Insulation resistance, PI and DAR with an insulation tester4 lessons
  3. 3Transformer tests: winding resistance, turns ratio, vector group and magnetising current9 lessons
  4. 4Tan delta and capacitance, and SFRA (concept)4 lessons
  5. 5Transformer oil: breakdown voltage and DGA interpretation (Duval triangle, IEC 60599)4 lessons
  6. 6Circuit breakers: contact resistance, timing, coil current, SF6 and vacuum checks7 lessons
  7. 7Switchgear and MCC preventive maintenance and torque checks2 lessonsLab
  8. 8Cables: insulation resistance, VLF and HV withstand, partial discharge (concept)4 lessons
  9. 9Motors: insulation, winding resistance, surge test (concept) and bearings8 lessonsLab
  10. 10Earth-resistance testing (fall of potential) and earth-continuity checks3 lessons
  11. 11Battery and UPS maintenance4 lessons
  12. 12Test records, trending and the annual maintenance plan1 lesson
  13. 13Final Assessment1 lesson

How it works

How this course works

  1. Watch the video lessonsOne module at a time, at your own pace.
  2. Take the module quizA short quiz at the end of each module shows what stuck.
  3. Keep your notesWrite in My notes beside each module and ask the trainer if you are stuck.
  4. Practise in the labOptionalTry a task from the module in the EDWartens Lab, in your browser.
  5. Sit the final examPass it once you have been through the modules.
  6. Certificate, if you want oneOptionalPaid, and only after you pass. Anyone can check it online.

EDWartens Lab

Practise this in the EDWartens Lab

Read the single line diagram, then isolate, lock and tag a motor bucket in the Lab's substation and MCC room.

Works alongside Testing and Maintenance of Transformers and Switchgear. The Lab is substation and mcc practice in your browser: no install, no hardware, free to use. Sign in as a learner and it opens with your account.

Open the free lab See the Lab
Substation and MCC: Work a real switchroom.

Levels to try with this course

Optional. Skip it whenever you like: it never blocks your progress or your certificate.

Why practise in a lab

Technical work is judged on what you can do: wiring, commissioning, finding a fault. Doing a task yourself teaches more than watching it a second time, and a lab lets you try it safely before you meet real equipment. It does not replace working on real hardware.

  • Practise safely, so a mistake costs nothing.
  • The lab checks your work like a site test, so you know when it is right.
  • Free, in your browser, with nothing to install.

Certificate

An optional certificate when you pass

Learning is free. Pass the final exam and you can have a certificate for £19, including VAT, with a number employers can check online. It records that you completed a free online course; it is not a regulated qualification or a CPD certificate.

  • Your name, the course, its study time and your final exam score
  • A unique certificate number and a QR code to its verification page
  • Issued by Wartens Ltd; add it to your LinkedIn profile in one click
  • Pay now or after you pass: it is issued the moment you pass the final

How the certificate works

Sample certificate for Testing and Maintenance of Transformers and Switchgear

Credits

Who made the lessons

The video lessons belong to their creators. EDWartens wrote the study plan, notes, quizzes and the final exam.

  • ElectroQC Hub

    the Power Transformer Testing playlist on a 100 MVA transformer: nameplate, insulation resistance with and without the HV link, core insulation, winding resistance, turns ratio, vector group, excitation current, magnetic balance, short-circuit impedance, zero-sequence impedance, tan delta and capacitance, SFRA and dielectric frequency response

  • Megger US

    webinars on insulation resistance testing, transformer turns ratio best practice (https://www.youtube.com/watch?v=Q6dCoXA-xpc), power factor and DFR for insulation assessment (https://www.youtube.com/watch?v=kot_OkvL3F8) and practical VLF cable testing (https://www.youtube.com/watch?v=lDOwXagByV8)

  • Megger

    medium and high-voltage circuit breaker testing, VLF tan delta (https://www.youtube.com/watch?v=0aBUGgfNDIE) and partial discharge tests on cables (https://www.youtube.com/watch?v=U-UIcDAK3oM), partial discharge on surge testing with the Baker DX (https://www.youtube.com/watch?v=dBwVVWf_dR0), battery load testing practice (https://www.youtube.com/watch?v=INn6FO2WdUE) and running a battery discharge test (https://www.youtube.com/watch?v=XVqNf-Qrjjs)

  • Megger Australia

    a webinar on medium and high-voltage circuit breaker testing

  • OMICRONenergy

    circuit breaker testing with CIBANO 500 on medium and high-voltage breakers (https://www.youtube.com/watch?v=COvybldgmWw, https://www.youtube.com/watch?v=vCcvDZCJ6Ik) and the Basics of Rotating Machine Testing series: insulation resistance and PI, tan delta, voltage withstand, partial discharge and the Energy Talks overview (https://www.youtube.com/watch?v=-7tjscOg08w)

  • AEMC Instruments

    fall-of-potential earth resistance testing in full, and understanding ground resistance testing (https://www.youtube.com/watch?v=NP9Jbdi_k6s)

  • Global Test Supply

    a webinar with Megger on how ground testing keeps people safe: fall of potential, clamp-on and continuity testing

  • Safety+Health YouTube channel

    webinars on NFPA 70B and the maintenance of electrical equipment, and on building an electrical maintenance programme (https://www.youtube.com/watch?v=B_bneVLRNLc)

  • Vector Power

    understanding the 2023 edition of NFPA 70B

  • Electrical Code Academy, Inc.

    the NFPA 70B and NETA severity scales for electrical thermography

  • GlobeCore company

    the Duval triangle method for transformer diagnostics

  • Oil Analysis

    dissolved gas analysis interpretation

  • Gulf Bio Analytical Group

    dissolved gas analysis with a transformer oil gas analyser

  • Motwane Manufacturing

    the transformer oil breakdown voltage test procedure, demonstrated

  • The Electrical Guy

    vacuum circuit breaker maintenance and testing

  • Electrical in Industry

    SF6 gas testing for moisture, purity and decomposition products

  • IPECLTD

    what partial discharge is

  • BakerInstrumentCo

    surge tests on motor windings with the Baker DX

  • TPC Training

    a webinar on electric motor troubleshooting and maintenance techniques

  • Electrical Superintendent

    motor maintenance, and substation battery impedance testing (https://www.youtube.com/watch?v=q0RMYkSSFfE)

  • ITM Instruments Inc.

    a webinar on UPS and battery maintenance

  • Reliability Centered Maintenance

    what reliability-centred maintenance is

  • Skill Torque

    reliability-centred maintenance explained

  • Engineering Presentations

    the philosophy of reliability-centred maintenance

  • Asset Insights

    the three main maintenance strategies compared, used as the revision lesson before the final

Questions

About this course

Who is this transformer testing course for?
Maintenance engineers and technicians, testing and commissioning engineers, and final-year electrical students who test and look after transformers, switchgear, cables, motors and batteries. It suits people applying for testing and commissioning and electrical maintenance roles worldwide, notably in the Gulf, where these tests are everyday work.
What do I need to know before starting?
How a transformer, a circuit breaker and an induction motor work, and how to read a single-line diagram. No test-set experience is needed: each test is explained from what it measures to how its result is judged.
Do I need test equipment or software?
No. Every test is planned and its results worked on paper or in a free spreadsheet such as LibreOffice Calc. Access to an insulation tester, micro-ohmmeter or turns ratio tester at work makes the course more practical, but only under your site's safety rules and permit to work.
Which standards does the course use?
It works with IEEE 43 for insulation testing of machines, IEC 60076 for transformer tests, IEC 60156, IEC 60422 and IEC 60599 for oil and dissolved gas analysis, IEC 62271 for breakers, IEEE 400.2 for VLF cable testing, IEEE 81 for earth resistance, IEEE 450 for batteries and NFPA 70B for maintenance programmes. It paraphrases these standards rather than reproducing them; check the edition your client specifies.
How is this different from the Protection Relays course?
This course tests and maintains the primary equipment: transformers, breakers, cables, motors, earthing and batteries. Protection Relays: Settings, Testing and Commissioning covers the relays that protect them, with CTs, settings, secondary injection and trip checks. Taking both covers most of a testing and commissioning engineer's work.
How long does the course take?
About 25 hours of video lessons, notes and practice, taken at your own pace; the videos alone are about 19 hours. The optional project, a condition review of a transformer and its breaker from a year of test results, takes about 8 hours more.
Is the course free, and what certificate do I get?
Every module, the notes, the project and the final assessment are free. If you pass the 15-question final at 60 percent you can get an EDWartens Certificate of Completion, with a number anyone can verify on our site. It is a certificate of completion, not a NETA certification, a licence or a qualification from any test-equipment maker.
What jobs does it lead to?
Electrical maintenance engineer and technician, testing and commissioning engineer, substation maintenance and transformer service roles with utilities, plants, facilities contractors and testing companies. Employers will still expect hands-on time with test sets, which this course prepares you to use well.

The Professional Module is five live days of Siemens PLC, HMI and SCADA with an instructor, then a resume session and a CPD certificate.

See the Professional Module