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Future proofing your Power Quality measurement equipment with IEC 61000-4-30 third edition

Power quality

What is IEC 61000-4-30 standard?

The IEC 61000-4-30 standard ensures that the measurement results from Power Quality analyzers and loggers of different makes and models match up; so measurement results are comparable without any doubts. This is extremely important, especially when there is a dispute about supply voltage quality between different parties going on. To comply with this standard, the instruments should measure and evaluate in exactly the same way. The standard covers PQ phenomena like voltage dips, swells, interruptions, frequency, harmonics and flicker. The standard specifies the required accuracy for the measurement of voltage, current, frequency and time.

Edition 2 of this standard, obsolete since 2015, covers voltage parameters only which makes it in principle possible that each manufacturer applies another current measurement technique. Mutual differences in current measurement results may occur and the same goes for rapid voltage changes.

IEC 61000-4-30 edition 3

Edition 3 of this IEC standard includes for example measuring of current parameters and verification of Rapid Voltage Changes (RVC). It anticipates on an increasing need for correct, standardized measurements of these parameters now and in the future.

We briefly discuss three parameters that are included in the 3rd edition:

  • Rapid Voltage Change (RVC), for example, defined as fast changes in voltage level, is a phenomenon that affects the power quality perception, though the voltage complies to limits in EN 50160. RVC assessments are already mandatory in many national power quality standards. It is expected that RVCs will be included in the first next revision of EN 50160. (today RVC is an informative Annex of EN 50160)
  • Current harmonic measurements will be an increasing task for power distributors to assess for example the current harmonics in the power, injected into the network by overproducing solar installations. To ensure that all results that are obtained with different analyzers are comparable and remain valid even in a dispute, all analyzers and loggers should be certified to the latest edition of IEC 61000-4-30.
  • To identify the cause of an event, the voltage and current trend plots are compared and therefore it is critical that these measurement values are synchronized. By adding “recording of current along with voltage during events” to IEC 61000-4-30 ed 3, for effective event cause analysis and conclusions.
IEC 61000-4-30 Ed2, published in 2005, replaced in 2015, specifies next parameters, all covering voltage:IEC 61000-4-30 Ed3, published in 2015 and making edition 2 obsolete, includes the parameters in ed 2 and also:
  • Power frequency
  • Magnitude of supply voltage
  • Flicker
  • Supply dips/swells
  • Voltage Interruptions
  • Unbalance
  • Harmonics
  • Inter harmonics
  • Mains signaling
  • Under- and over-deviation
  • Rapid voltage changes
  • Flicker class F1
  • Measurements in the 2 kHz-150 kHz frequency band
  • Magnitude of the current
  • Current unbalance
  • Current harmonics
  • Current inter harmonics
  • Recording of current along with voltage
Table 1. parameters that are included in standard ed 2 and ed 3

Annexes

In the current version of the standard Edition 3, there are additional annexes (A-D) included, that cover Power Quality measurements – Issues and guidelines, Guidance for Applications, Conducted emissions in the 2 kHz to 150 kHz range, under deviation and over deviation. These are informative and as such instruments can comply without having to meet the requirements in those annexes.

Certification

To satisfy end-users, power quality measuring equipment needs to fully comply with the standard. Special tests and procedures should be conducted by independent laboratories, like TüV, NMI and UL and the methods used are described in IEC 62586-2. The total costs for certification are considerable.

When users are evaluating measurement equipment they should request a copy of the document certifying that the equipment fully meets the standard. These documents sometimes appear on manufacturers websites or are available on request.

Future proof

When setting up a list of requirements for a new Power Quality analyzer or logger, consider that it should be rugged, reliable, and can cope with future developments on power quality regulation. Certification according to IEC 61000-4-30 ed 3 should have top priority!