Results of an intercomparison for electric field strength measurements within the German calibration service

Abstract

In this paper we discuss the results of an intercomparison for electric field strength measurements within the German Calibration Service (Deutscher Kalibrierdienst – DKD). The comparison has been carried out on the field strength value required to reach a display reading of 20 V m−1 of the field probes for frequencies between 100 MHz and 18 GHz. Five laboratories joined the intercomparison including the Physikalisch-Technische Bundesanstalt (PTB), the German National Metrology Institute that keeps the primary standard for electric field strength. As measurement artefacts both a small 1-axis probe usually used as transfer sensor at PTB and a larger 3-axis commercial field probe have been used. While the results agree well for the small field probe and when the larger commercial 3-axis field probe is oriented in the direction of the magnetic field, larger deviations occur, when the larger 3-axis field probe is oriented into the direction of the Poynting vector of the calibration field.