Title :
Realization of the farad at BNM-LCIE
Author :
Trapon, G. ; Thevenot, O. ; Lacueille, J.C. ; Geneves, G.
Author_Institution :
Lab. Central des Ind. Electr., Bur. Nat. de Metrol., Fontenay-aux-Roses, France
Abstract :
The BNM-LCIE Thompson Lampard Calculable Capacitance (TLCC) has been taken apart for improvements between 1994 and 1997. Influencing parameters were determined and/or corrected: parallelism of the electrodes, end effects, dimensions of a compensating spike and effect of its lateral displacement. With these improvements and by using a new interferometer, the realization of the farad is achieved with an uncertainty (not taking into account the frequency dependance of the TLCC) equal to 3 10/sup -8/ (1/spl sigma/).
Keywords :
capacitance measurement; electrodes; error compensation; measurement standards; measurement uncertainty; units (measurement); BNM-LCIE Thompson Lampard Calculable Capacitance; Lampard theorem; Michelson interferometer; compensating spike dimensions; cylindrical defects; electrodes parallelism; end effects; farad realization; five horizontal electrode bars standard; fringes interpolation; lateral displacement; linearity; ratio bridge; uncertainty; Bars; Bridge circuits; Capacitance; Capacitors; Electrodes; Equations; Fasteners; Frequency; Uncertainty; Vacuum systems;
Conference_Titel :
Precision Electromagnetic Measurements Digest, 1998 Conference on
Conference_Location :
Washington, DC, USA
Print_ISBN :
0-7803-5018-9
DOI :
10.1109/CPEM.1998.699997
