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EDWartens UK

Free course · Electrical

Protection Relays: Settings, Testing and Commissioning

Protection relays from the CT to the commissioning record: faults and zones, CTs and VTs, fuses and IDMT curves, overcurrent and earth-fault grading by hand, transformer differential and REF, distance, motor and generator protection, numerical relays and COMTRADE, then primary and secondary injection, trip-circuit and stability tests, and maintenance.

See the modules

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

Level
Intermediate
Modules
13
Video
24 hours
Price
Free

Outcome

What you will be able to do

Explain why power systems are protected and draw overlapping zones; calculate fault currents from fault levels; check a CT's class and knee point for its duty; read fuse, trip-unit and IDMT curves and calculate IEC and IEEE operating times; set and grade overcurrent and earth-fault relays by hand; set transformer differential and REF protection with ratio and vector compensation; set three-zone distance protection in secondary ohms; set motor and generator protection; manage settings files and read event reports and COMTRADE records; plan and interpret primary injection, CT excitation and secondary injection tests with expected times and tolerances; prove trip circuits and run stability tests; and plan relay maintenance at sensible intervals.

  • Calculate fault currents from fault levels and draw overlapping zones of protection
  • Check a protection CT's class and knee point against the voltage its duty needs
  • Calculate IEC and IEEE inverse-time trip times and read fuse and LSIG trip-unit curves
  • Set and grade overcurrent and earth-fault relays by hand with a stated margin
  • Set transformer differential with ratio and vector compensation, and design a high-impedance REF scheme
  • Set three-zone distance protection in secondary ohms, and motor and generator protection
  • Manage relay settings files and read event reports and COMTRADE records
  • Plan primary injection, CT excitation, secondary injection, trip-circuit and stability tests with expected results

Software

A spreadsheet (LibreOffice Calc is free) for the grading and test sheets. SEL ACSELERATOR QuickSet to see how settings are entered, and a COMTRADE viewer, are useful but optional. A relay test set is not required: every test is planned and its results worked on paper.

Hardware

None required. Access to a numerical relay and a secondary injection test set at work or college makes the testing modules far more useful.

Syllabus

13 modules

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

  1. 1Why protect: faults, zones, selectivity and speed2 lessonsLab
  2. 2CTs and VTs: ratio, class, knee point, polarity and saturation4 lessons
  3. 3Fuses, MCCB trip units and IDMT curves4 lessonsLab
  4. 4Overcurrent and earth-fault settings and grading by hand5 lessonsLab
  5. 5Transformer differential and restricted earth fault4 lessons
  6. 6Distance protection for lines: zones and reach5 lessons
  7. 7Motor and generator protection7 lessons
  8. 8Numerical relays: settings files, disturbance records and COMTRADE6 lessons
  9. 9Primary injection and CT tests: ratio, polarity and magnetising curve7 lessons
  10. 10Secondary injection: pick-up, timing and characteristic tests10 lessons
  11. 11Trip-circuit checks, stability tests and commissioning records5 lessons
  12. 12Relay maintenance, test intervals and faults commonly found4 lessons
  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 Protection Relays: Settings, Testing and Commissioning. 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 Protection Relays: Settings, Testing and Commissioning

Credits

Who made the lessons

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

  • Romero Engineering Company

    the Power System Protection and Control lessons: CT basics and saturation, calculating SEL and IEEE inverse-time trip times, overcurrent basics, neutral overcurrent of transformers, directional control, transformer differential TAP and compensation settings, harmonic restraint and blocking, restricted earth fault, distance protection, infeed, load encroachment, POTT, motor differential, trip event analysis, one-line and three-line drawings, breaker failure protection and symmetrical components

  • OMICRONenergy

    the Test Universe lessons (QuickCMC, Ramping, Overcurrent, State Sequencer, Advanced Differential, Advanced Distance, Annunciation Checker and XRIO test automation) and the CT Analyzer lessons on protection CT testing, multi-ratio CTs and remanence (playlist https://www.youtube.com/playlist?list=PLzmbZeI1bhu-bwtPfgxqAFE-LyK4DzX0h)

  • NPTEL IIT Kharagpur

    NPTEL Power System Protection lectures on current transformers, capacitor voltage transformers, overcurrent relay characteristics, overcurrent coordination, relay coordination with fuses and the numerical relaying concept

  • IIT Roorkee July 2018

    NPTEL Power System Protection and Switchgear lectures on the fundamentals of protective relaying, current-based relaying, distance protection of lines, transformer protection, induction motor protection, and testing, commissioning and maintenance of relays

  • Hamada Diab

    the Generator Protection Training Series (basics and earthing, 87G differential, reverse power, loss of field, thermal overload) and the Test Universe overcurrent module lesson on a Siemens 7SJ85

  • Schweitzer Engineering Laboratories (SEL)

    the ACSELERATOR QuickSet Device Manager overview, and setting SEL-751 overcurrent and time-overcurrent protection (https://www.youtube.com/watch?v=EtdRdL7Q1is)

  • Testing Tech Tips

    downloading and installing settings on SEL relays with ACSELERATOR QuickSet

  • Power Globe

    disturbance recorder analysis and the COMTRADE standard, and NERC PRC-005 protection system maintenance (https://www.youtube.com/watch?v=ciygSshMbr8)

  • Doble Engineering

    performing a current transformer excitation test

  • Megger

    performing a manual timing test on a protective relay

  • TestGuy

    circuit breaker electronic trip units explained

  • Electrical Passionate

    pre-close and post-close trip-circuit supervision, and calculating currents for a transformer REF stability test (https://www.youtube.com/watch?v=64P0_NgGq9w)

  • Circuit Masterclass

    protection zones and why they overlap

Questions

About this course

Who is this protection relay course for?
Electrical engineers, testing and commissioning engineers and technicians, utility and plant electrical staff, and final-year electrical students who need to set and test protection relays. It suits people applying for testing and commissioning roles worldwide, notably in the Gulf, where relay testing is a standard job requirement.
What do I need to know before starting?
Three-phase power, per-unit quantities and the basic idea of a short circuit. Symmetrical components and per-unit are revised where they are used. No relay or test set experience is needed.
Do I need a relay test set or software?
No. Every setting is calculated by hand or in a free spreadsheet, and every test is planned and its results worked on paper. SEL ACSELERATOR QuickSet and a COMTRADE viewer help you see real settings files and records, and access to a test set at work makes the testing modules more practical.
Which standards does it follow?
The IDMT curves are the IEC 60255 inverse curves and the IEEE C37.112 curves used by numerical relays, records use the COMTRADE format, and maintenance intervals use NERC PRC-005 as a worked example. The course paraphrases these standards; it does not reproduce them, and you should check the edition your plant uses.
How is this different from the ETAP course?
The ETAP Power System Analysis course runs coordination studies in software. This course does the grading by hand and then proves the settings with primary and secondary injection, the way a commissioning engineer works. Taking both is a good combination.
How long does the course take?
About 23 hours of video lessons, notes and practice, taken at your own pace; the videos alone are about 17 hours. The optional project takes about 10 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 licence or a vendor qualification from SEL, OMICRON or any test-set maker.
What jobs does it lead to?
Protection testing and commissioning engineer and technician roles with contractors, utilities and EPC firms, substation maintenance roles, and protection settings work in consultancies. 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