Comparison of AC current ratio standards in the range up to 4 kA
Renata Styblíková, Karel Draxler, Emil Dimitrov, Ginka Kumanova, Erik F. Dierikx · 2010
Measurements were carried out at the Czech Metrology Institute (CMI) and at the Bulgarian Institute of Metrology (BIM) in the range of transformation ratios up to (0.5 - 4 000) A/5 A, and the results were compared. Attention focused on the results in the range (1 up to 4) kA/5 A when the primary winding was formed by one conductor. This paper presents the results of the comparison. The influence of the position of the primary conductor in the magnetic circuit of the transformer is particularly described. The impact of the stability of the magnetic parameters of the core of the instrument current transformer (ICT) on the measurement results is also discussed.