Omicron has released a paper that highlights the importance of regularly testing power quality instruments, as well as how to perform such a test and the appropriate procedures for testing.
Due to the increasing number of distributed energy resources, non-conventional loads and non-linear elements in the power grid negatively impact on its power quality.
Regulating standards, such as EN 50160 or IEC TS 62749, force utilities to prove their power quality conformity. As a consequence, more and more power quality instruments are installed in the electrical network and at connection points which should be tested periodically.
Other than with protection relays, there are no commonly established rules or procedures for installation and routine testing or calibration. Furthermore, there is little experience and a lack of awareness for power quality, especially in small utilities, industry and at end-use customers.
Therefore, malfunctioning or reduced accuracy can remain unnoticed, although they may have significant monetary impact. This paper describes how to test a power quality instrument as well as appropriate procedures for type, acceptance and routine testing.
What’s in the paper?
Initially this paper briefly describes the existing framework of IEC standards for testing power quality instruments. For manufacturer type testing and comparable acceptance testing in utilities, a set of test plans for guided testing of power quality meters according to IEC 62586-2 is presented.
Already existing test plans provided by a test set manufacturer have been completely reworked to reflect recent changes in the standards, provide test guidance to users and specially to give substantial support for the test assessment.
Findings from testing a typical PQ meter are discussed. In addition, the paper introduces a suitable subset of tests for field testing during commissioning or routine testing of PQ meters.
How can I read Omicron’s paper?
Omicron’s paper on power quality instrument testing is available from the company’s website.