Contact person
Ove Gunnarsson
TIC-ingenjör
Contact OveCalibration of electrical resistance
The National Laboratory for electrical quantities offers calibration of resistance standards and various types of other instruments, such as calibrators, multimeters, LCR meters and certain types of temperature measuring instruments.
Purpose
RISE's calibration at the National Laboratory for electrical quantities is available to customers who require the best possible accuracy in their calibration or have requirements which involves development of new calibration methods. Our customers are found among industry, research institutes, and calibration companies. Our national standards have the highest level of accuracy in Sweden. The traceability to the realisation of the unit is always ensured.
Calibration at a National Laboratory meets all the requirements for traceability and accreditation commonly found in industry and society at large.
Method
The calibration resources for resistance are in the range of 1 μΩ - 10 PΩ and calibration is usually carried out using resistance bridges or TΩ meters. Most types of instruments are calibrated against secondary resistance standards. The measurement uncertainty is at best 0.25 μΩ / Ω in these cases.
For resistance standards in the range 1 Ω - 10 kΩ, we can in some cases offer direct calibration against our primary resistance standards with our cryogenic current comparator (CCC). The measurement uncertainty will be 0.05 μΩ / Ω at best.
Calibration of AC resistance can be offered in the range 1 Ω - 100 MΩ for frequencies up to 10 kHz. The calibration is done with an ac-resistance bridge or LCR meter, so-called substitution measurement. The LCR meters have in turn been calibrated by measuring against secondary ac resistance standards. The measurement uncertainty is at best 5 μΩ / Ω.
Other types of measurements are also performed, such as determination of temperature coefficient and resistivity.
The measurement uncertainty given for a calibration depends, in addition to the calibration equipment's performance, also on the calibration object's performance (stability, temperature coefficient, voltage dependence and so on). In most cases, a preliminary estimate of the measurement uncertainty can be given from experience before the calibration.
For more information on our resistance standards and the realisation of the resistance unit, see our expertise page on electrical resistance.
Deliveries
Delivery upon agreement with customer. The results of the calibration are reported in a calibration certificate.