Transformer specification course - e-lesson #8 - illustration 850 x 400

E-lesson: Transformer specification course – e-lesson #8: Classification of technical requirements – ‘essential versus optional’

Course: Master’s level

This is the second Master's level e-lesson in the Transformer specification course, authored and conducted by Mr. Marcos Ferreira. Here you can save room link.

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Attend the lesson to learn the following:


  • Ratings (e.g., phases, frequency, windings, impedance, short-circuit characteristic, sound levels, angular displacement, total losses – load and no-load, insulation levels, temperature rise, load conditions, and cooling classes)
  • Construction (e.g., tank types, high & low voltage bushings, OLTC, DETC, and surge arresters)
  • Accessories (e.g., pressure relief devices, winding & liquid temperature gauges, liquid insulation types, grounding, and sudden pressure relay)


  • Choose liquid insulation
  • Choose LTC
  • Choose accessories: time-based maintenance (conventional) versus condition-based maintenance (maintenance-free)
  • When to consider adding DGA/bushings/OLTC online monitoring?
  • What is the main difference between OLTC and DETC and when are OLTC versus DETC specified?
  • What is the main difference between OLTC and VR (voltage regulator)?
Marcos Ferreira

Marcos Ferreira

Marcos Ferreira is an electrical engineer experienced in designing, managing, and coordinating projects relating to transmission, distribution, and communications. He works on installation and replacement of HV substation equipment based on standard design including system protection and commissioning. His areas of expertise also include interpreting and applying the National Electrical Codes (NEC) as a project manager (including scoping a project based on PRD – Project Requirement Diagram, Chapter 9 Tables & Annex C), as well as maintaining and testing substation HV equipment and providing technical support for planning and operation groups.

Juan Albiger 300 x 300

Juan Albiger

Juan Albiger is an electrical engineer with over ten years of experience in power transformer procurement process.
He is specialized in HV substation equipment: preparing technical specifi cations, performing factory inspections, and managing commissioning and maintenance.
Mr. Albiger is the Head of Department responsible for ensuring the procurement and commissioning of high voltage substation equipment, power transformers and reactors that are fit for purpose.

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