Abstract :
Since the harmonic voltage standards ER G5/3 were set in 1976 there has been an enormous increase in the amount and complexity of electronic equipment connected to the electricity network. There is little doubt that the designers of these devices will have considered the harmonic voltage standards when deciding what level of immunity to build in. The result of this is that the electricity supply industry has not, in general, had a problem with customers complaining of equipment failure due to harmonics. Work has been going on to produce European and world-wide standards. These, too, will set limits on the levels of harmonic voltage. It is reasonable to expect that the limits will be similar to those in ER G5/3. The author discusses how the electricity supply industry has worked with the standards, experiences with harmonic distortion, and associated effects in the network