№ KZ.01.01.00053-2010 in the register of the SSM of the Republic of Kazakhstan.
Operated since 2003.
Composition of the standard:
- automatic bridge-comparator of direct current model MI 6010Q, produced by Measurements International Limited, Canada;
- 10-channel, 4-terminal matrix scanner model MI 4210A - Dewar vessel with superconducting magnet, manufactured by CryoIndustries, USA; - Cryosonde with heterostructure;
- Digital vacuum meter;
- Vacuum pump;
- Power supply of superconducting magnet model 625, produced by LakeShore, USA;
- The gauge and the monitor of level of helium of model LM-500, manufactures «CryoMagnetics», the USA;
- Stand with built-in system unit, monitor and keyboard.
- The reproducible value of the electrical resistance unit is 12906.4035 Ohm;
- The estimation of the standard deviation of the measurement result (SΣ
) does not exceed 2•10-8
with 35 independent observations;
- The non-excluded systematic error does not exceed 5•10-8
- The expanded uncertainty is 5•10-8
ohms with a coverage factor of k = 2, a confidence level of P = 0.95;
Sources of traceability:
In 1987, at the 18th session of the General Conference on Weights and Measures, a recommendation was adopted on the transition from 01.01.1990 to a new way of representing a unit of electrical resistance by implementing the QHE (von Klitzing constant). The standard based on the QHE is recognized as the natural standard of the unit of electrical resistance, the size of which is unchanged in time and is tied to the ratio of fundamental constants:
where is h - the Planck constant; e - is the electron charge; i- is a natural number..
The standard based on the QHE makes it possible to obtain the most stable quantization steps for i = 2; 4, which corresponds to the values of KCh 12906.4035 ohms and 6453.20 ohms, respectively, with an accuracy of 1 • 10-8
, and transfer the unit resistance size to resistance measures and standards of the traditional type.
The transition to natural standards allows one to reproduce units of physical quantities regardless of time, place and external conditions. The principle possibility of such reproduction is based on the in distinguish ability of identical particles and universality and the simplicity of laws governing elementary quantum phenomena.
The standard based on the quantum electrodynamics is designed to reproduce the second quantization stage, which corresponds to a value of 12906.4035 Ohm, with an accuracy of 1•10-8
, and transfer the unit size of resistance to resistance measures.
Location: Reference Center, Astana