PTB - UNIIM bilateral comparison on current transformer measurement systems at currents up to 60 000A

This paper presents the results of a bilateral comparison of current transformer measurement systems at 50 Hz between PTB (pilot laboratory) and UNIIM. The comparison is registered at COOMET with the identifier 513/DE-a/10. The comparison of the systems using two two-stage current transformers from UNIIM and the data processing have been finished. The results agree within 6 μA / A for the current ratio errors and 8 μrad for the phase displacements at all current ratios from 1 A / 1 A to 50 kA / 5 A and at all test points from 1 % to 120 %. The associated EN factors are below 0.6.