INFLUENCE OF DVM'S INPUT PARAMETERS ON DVM-BASED HIGH-OHM RESISTANCE COMPARISON

摘要

Establishment and maintenance of resistance standard traceability is one of the main tasks of Primary Electromagnetic Laboratory (PEL) within the Faculty of Electrical Engineering and Computing of the University of Zagreb. For the purpose of accurate resistance standards comparison a digital voltmeter (DVM) based method has been designed and realized. When measuring resistance standards greater than 10 MΩ capabilities of the method are restricted due to influence of DVM's input parameters: input DVM's resistance, input offset current and input capacitance. Determination of DVM's input parameters and their contribution to the overall high-ohm resistance comparison uncertainty has been presented in this paper. The possibility of use of DVM-based method for gigaohm value resistors comparison has also been investigated.