Omicron roadshow bus

Roadshow Bus to Host Technical Tutorial on Testing Transformers

Omicron will present an informative technical tutorial, “A New Approach for Testing Instrument Transformers,” on its Roadshow Bus in Booth 2739 during the 2014 IEEE PES T&D Conference & Exposition in Chicago. Three 20-minute sessions led by training and application engineer William Yu are scheduled for Tuesday, April 15 at 11:30 a.m.; Wednesday, April 16 at 1:30 p.m.; and Thursday, April 17 at 12:30 p.m.


In order to precisely determine the current ratio error and phase displacement of the current transformer (CT) or voltage transformer (VT), typically the primary injection method is used especially for the ones with metering accuracy. This conventional method uses nominal primary current/voltage to energize the primary side of CT/VT and measures the secondary current/voltage with standard burden connected. With this, the load-dependent ratio error and the phase displacement can be measured.

However, due to the requirements of high voltage and current sources, this conventional method is subject to many practical limitations in particular to on-site measurement. New innovative test methods have been invented which make CT or PT testing so much easier than before. Learn about how the new approach evaluates the accuracy class, ratio error and phase displacement of instrument transformers according to the IEEE, ANSI and IEC Standards.

William Yu received his BEng(Hon) degree and his MSc degree from the Hong Kong Polytechnic University in 2006 and in 2010 respectively. In 2006, he joined OMICRON electronics Asia in Hong Kong and was responsible for technical and application support for both primary and secondary testing in Asia-Pacific. In 2008, with sales and application support responsibilities, he conducted many training programs and performed field demonstrations in different countries. His experiences include performing various primary tests on power transformer, instrument transformer and power cable. He is currently working in OMICRON's office in Waltham, Massachusetts as a training and application engineer.

Omicron bus classroom

Hide comments


  • Allowed HTML tags: <em> <strong> <blockquote> <br> <p>

Plain text

  • No HTML tags allowed.
  • Web page addresses and e-mail addresses turn into links automatically.
  • Lines and paragraphs break automatically.