A 100000-ampere series high precision on-site measurement calibration device for heavy direct current

A 100000-A series high-precision on-site calibration device for measuring high direct current of a magnetic modulation comparator type is presented. The device can be used in an industrial system for online calibration and measurement. Testing of the comparator shows that its accuracy for measuring current ratio is 5×10^.5 and for measuring voltage with a standard resistance is 3×10^.4 (on-site calibration), 5×10^.4 (accurate measurement), or 1×10^.3 (on-site measurement). The error in repeatability for measuring open-loop cores is 2×10^.5, and its antimagnetic ability with respect to the external magnetic field is 1×10^.2 Tesla. The author discusses the principle of operation and characteristics of the comparator, the antimagnetic principle, and the analysis of comparator errors