Four terminal-pair inductance comparison between INRIM and CTU

Since forty years, it is known that four terminal-pair (4TP) definition permits to achieve the highest accuracy in impedance measurement. While for ac resistors and capacitors 4TP standard definition is commonplace, and 4TP commercial measurement systems are available on the market, for inductance two-or three-terminal definition is still the most common. In the following, we describe the first international intercomparison of inductance performed with 4TP measurement systems and a 4TP travelling standard of nominal value of 100 mH. Despite the difference in traceability and measurement techniques employed, results show a high degree of compatibility.