The impact of IEC 555 on IT equipment-Part 2: Harmonics

IEC 555 comprises a series of documents dealing with disturbances caused by equipment connected to the public low voltage supply network. There are three published documents: part 1: Definitions (IEC Publication 555-1, Guide); Part 2: Harmonics (IEC Publication 555-2, Standard); and Part 3: Voltage fluctuations and flicker (IEC Publication 555-3, Standard). Within IEC, Sub-committee 77A is responsible for the work on these documents. The changes proposed to IEC Publication 555-2, Harmonics, are likely to impact to design of almost all IT equipment up to 16 amps per phase. The author reviews the background to IEC 555-2 and considers how it may affect information technology equipment