An EMC market surveillance project for frequency converters in Finland

Three EMC market surveillance projects have been carried out in Finland. The first project was for uninterruptible power systems, the second was for personal computers and the latest one has been for frequency converters. The project required the Finnish frequency converter market be monitored and manufacturers and importers identified. Much documentation was requested and thoroughly checked. Altogether 24 different frequency converter unit types were EMC tested. In the authors´ particular project, only emissions were tested. They did not consider immunity tests to be necessary, since the requirements for immunity are easier to achieve. The manufacturer must, at any rate, ensure that the circuits of a frequency converter are immune to emissions made by the drive itself. In this paper, test results are given, analyzed and compared with results received from Sweden