Bilateral Comparison of the Measurement of Current Transformers Between UME and NCM

Project Description

As a result of request from NCM, this bilateral comparison was planned between UME and NCM. UME will be the pilot laboratory and a 3 kA current transformer (NCM-owned) will be used as a transfer standard. Measurements will be performed at 50 Hz.1000, 500, 200, 100, 50, 20, 10, 5 & 1:5 A ratios of the transformer will be used.All ratios will be measured with a burden of 5 VA at unity power factor and with the following % of rated current:120, 100, 50, 20, 10, 5 & 2%.

Final Report 2011-02-10

The comparison has been completed and results are available in the KCDB.

As a result of request from BIM (formerly NCM), this bilateral comparison was planned between UME and BIM. UME acted as the pilot laboratory and a 3 kA current transformer (BIM-owned) was used as a transfer standard. Measurements were made at 50 Hz.
The 1000, 500, 200, 100, 50, 20, 10, 5A : 5 A ratios of the transformer were used. All ratios were measured with a burden of 5 VA at unity power factor and with the following % of rated current: 120, 100, 20, 10 and 5%.
The main targets of the comparison were to demonstrate equivalence of metrological practice and to check the correctness of the calibration results. The results of the measurements showed a good agreement between BIM and UME both for the ratio errors and phase displacements.