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    OLTC Course – FREE lesson #1: On-load tap-changer basics

    Course: | Free Basic level

    Hosted by: Raka Levi

    This is the first lesson of the OLTC course conducted on the basic level. Join us for this interactive session and dive deep with industry experts!

    In this event you will learn:

      • Foundational knowledge of load tap changers
      • Their purpose
      • The different construction types and operating principles of the patented process
      • Resistor and reactor constructions.

    The content of this lesson is fully vendor-agnostic, but it is sponsored by Huaming.

    If you are already a subscriber of the Transformers Academy or Transformers Maagazine, please, Login with your credentials..

    Also, we will present three types of regulation, and try to understand what is written on the OLTC nameplate.

    Key takeaways: Tap-changer definitions, OLTC, DETC, principle of operation and patented procedure, resistor and reactor constructions, three types of regulation, understanding the OLTC nameplate

    Keywords: tap changers, OLTC, regulation, transformers


    To know which level of this course suits your needs best, see the OLTC Brochure.

    To subscribe to the level of your choice, click here.


    Recommended browsers for the successful registration: Chrome, Edge, Mozilla, Safari

    We advise you to avoid using Internet Explorer, due to compatibility issues!

    About the author

    Raka Levi

    Raka Levi

    Levico, Inc.

    Electric-power engineer with over 30 years of technical experience in the field of asset management, condition assessment, power instrumentation, diagnostics and monitoring, tap-changer testing, and consulting services. Director of Levico, Inc. a consulting company in the USA.

    Over the last nineteen years operated from offices in Boston USA, Belgrade Serbia, Barcelona and Madrid, Spain to provide customized service to clients on all continents. Principle of operations – expert and consultant to multiple companies.

    Education: Dr. Sci. in the field of HV computerized condition assessment for circuit breakers at U. of Belgrade, and Master of Engineering in Electrical Power from the Rensselaer Polytechnic Institute, Troy – New York.

    Affiliations: Senior Member IEEE (USA), past vice-chairman of the IEEE working group for revision of IEEE standard C57-152

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