ГЭТ 4-91 (НИЛ 2201)
Standard name:
- ГЭТ 4-91 State Primary Standard of the Unit of Direct Electric Current
Type of measurement:
- Measurements of electrical and magnetic quantities
Structural division: name НИО\НИЛ:
- Research Laboratory of State Standards in the Field of Measurements of Electrical Circuit Modes
Guardian Scientist:
- Katkov Alexander Sergeevich, Doctor of Technical Sciences, Associate Professor.
Year of creation:
- 1968
Year of re-confirmation:
- 1991
Operating principle:
The methods for practical implementation of the standard are based on the 2019 recommendations of the Advisory Committee on Electricity and Magnetism, set out in the SI Brochure – 9th edition (2019) – Appendix 2. For current values of 1 10-3 A and 1 A, a method based on Ohm's law, I = U/R, is used, using the quantum Josephson and Hall effects. For current values in the range of 1 10-16 ÷ 1 10-9A, an electrometric method based on the relationship I = C dU/dt is used, using SI units such as farad, volt, and second.
Composition of the standard:
- A multi-valued DC current meter for values of 1 10-3 A and 1 A, including a voltage meter, electrical resistance meter, and adjustable current sources;
- A multi-valued DC current meter for the range of 1 10-16 ÷ 1 10-9 A, including a set of constant capacitance meter units, an integrator, a measuring unit with a frequency counter, a digital voltmeter, and a comparator.
Main metrological characteristics
| Range | RMS | NSP | uA | uB |
|---|---|---|---|---|
| 1 mA, 1A | 5·10-8 | 2·10-7 | 5·10-8 | 0.9·10-7 |
| 1·10-16 ÷ 1·10-9А | 1·10-2 ÷ 4·10-4 | 2.5·10-2 ÷ 5·10-4 | 1·10-2 ÷ 4·10-4 | 1.1·10-2 ÷ 2·10-4 |
Verification diagram:
- State verification scheme for measuring instruments of direct electric current in the range of 1 10^-16 ÷ 100 A
Scope of application:
- Electronics, space, and defense technologies;
- Instrument and precision engineering;
- Shipbuilding, aircraft and rocket engineering, etc.
Results of applying the standard:
The State Primary Standard of Direct Electrical Power reproduces, stores, and transmits the unit to secondary and working standards, as well as measuring instruments, ensuring the uniformity of measurements in this region of the Russian Federation.
The total number of measuring instruments traceable to ГЭТ 4-91:
The total number of measuring instruments traceable to the primary standard, according to the GPS, amounts to several million across the country. This includes calibrators and DC power sources, ammeters, multimeters, electrometer amplifiers, and others.
Ensuring the uniformity of measurements, participation in the CIPM MRA program:
EUROMET.EM-S24 comparisons,
5 CMC lines, including two matrices
Unique technical installations as part of the standard:
Thermostatically controlled resistance meter 1 ohm, 1 watt,
thermostatally controlled resistance meter 1 kohm, 1 mW,
set of capacitance meters КОГ-1,
precision linear voltage generator.
PHOTO:
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/Многозначная мера постоянного тока.png)
Multi-digit measure of direct current for values of 1·10-3 A and 1 A
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/Многозначная мера постоянного тока для диапазона.png)
Multi-digit measure of direct current for the range 1·10-16 ÷1·10-9A
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Scientist