Investigating DC Characteristics in Testing Precision Current Shunts for Steady State

This paper provides information on the performance study of precision current shunts in the context of their output voltage stability. Besides, it briefly focuses on the phenomena affecting the steady state of these measuring instruments. The authors present a methodology for testing current shunts to ensure a high-quality result of current measurement. The investigation highlights three characteristics of shunts (the dependence of resistance on temperature, the response of the output voltage to a fast increase of current, and the transition from a cold state to a warm one). The test equipment with precision shunts were considered during the experimental examination. The results of an investigation confirmed satisfactory operational properties and compliance with the needs of laboratories. Additionally, the authors emphasize using a precision shunt as a measuring standard when calibrating other instruments like high-precision digital ammeters. From this point of view, the simplified mathematical modeling of the change in the AC-DC transfer difference, depending on the resistance change caused by the warming current, was carried out.