On-load tap changers, also known as O-L-T-Cs, are devices fitted on to power transformers that regulate the output voltage to required levels to maintain a stable voltage level in the electrical grid.

To check the reliability of OLTCs, a variety of advanced diagnostic methods have been developed, including the new vibro-acoustic measurement (also known as VAM), which uses vibrations to assess OLTC condition.

In this episode of Energy Talks, OLTC diagnostic experts Dr. Karsten Viereck from Maschinenfabrik Reinhausen and OMICRON applications engineer Christoph Engelen talk about the origins and development of the vibro-acoustic measurement, how and when it is performed, how it compliments other OLTC diagnostic methods, as well as how the data is analyzed.

Learn how vibrations play a role in reliably assessing the condition of on-load tap changers.

On-load tap changers, also known as O-L-T-Cs, are devices fitted on to power transformers that regulate the output voltage to required levels. With the help of the O-L-T-C, the transformer turns ratio can be adjusted under load to deal with voltage fluctuations and maintain a stable voltage level in the electrical grid.


To reliably analyze and assess the condition of on-load tap-changers, advanced diagnostic methods have been developed, such as the dynamic resistance measurement (DRM). Complementary to this approach is the vibro-acoustic measurement, also known as VAM. It records the vibrations produced during the switching operation.


In this episode of Energy Talks, VAM diagnostic experts Dr. Karsten Viereck from Maschinenfabrik Reinhausen and OMICRON applications engineer Christoph Engelen talk about the origins and development of the vibro-acoustic measurement, how and when it is performed, how it compliments other OLTC diagnostic methods, as well as how the data is analyzed.


Find out more about our solution for VAM.


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