Electromagnetic compatibility between electronic loads and automated meter reading systems using PLC

According to Finnish legislation, at least 80 % of the energy meters in Finland have to be remotely readable and provide hourly based energy data by the end of 2013. Based on a questionnaire made to Finnish DSOs, a conservative estimate can be made that approx. 30...50 % of these meters will use PLC communication in LV network. In a sample of 110 647alredy installed meters approx. 3.6 % of the meters using PLC had experienced communication problems either in commissioning stage or during operation. On-site measurements to study common customer apparatus disturbing the PLC were conducted in the networks of a few DSOs. Most common disturbance sources were frequency converters and switch-mode power supplies. A method based on HF current measurements was developed to facilitate the location of the disturbance source. The measurements indicate that in addition to insufficient emission limit standardization below 150 kHz the aging of customer equipment is a relevant cause of interference problems.