The most dramatic change on the PQ market in 2026 is that the new version of the Power Quality standard IEC 61000-4-30 (Edition 4) has come into place. Much is the same as earlier, but the lower flicker accuracy F3 is no longer allowed. Only flicker accuracy F1 is accepted. For Unipower, there is no change since we have always complied with the higher accuracy version.
The second and even more important change is the new requirement on flagging. From now on, instruments shall not only flag data when a disturbance occurs. The flagging also needs to define whether it is caused by a sag, swell or interruption. Why is this important? It is because the majority of international norms, such as EN50160 and national adoptions, analyse data under normal operating conditions. This means that flagged data caused by sags and swells shall always be part of the evaluation, whereas data from interruptions shall be excluded. This is because harmonics go sky-high when the fundamental drops to zero – interruption data is irrelevant.
Additionally, there are also changes in the definitions of Rapid Voltage Changes (RVC) and Sag/Swells (polyphase dips).
Eager to know more about Edition 4? If so, join our free webinar: Quarterly Session on March 31.
Our Research Manager Jonny Carlsson, who has also been a member of the IEC 61000-4-30 working committee for 18 years, will present the key changes in Edition 4 and how these affect your operations.
