Automated Setup to Accurately Calibrate Electrical DC Voltage Generators

TL;DR

This paper presents an automated calibration setup for DC voltage generators that enhances accuracy, reliability, and efficiency, reducing the need for multiple standards and manual intervention in calibration processes.

Contribution

The development of an automated fixed ratios DC voltage divider system that automates calibration, improves accuracy, and reduces calibration time and operator involvement.

Findings

Achieved relative uncertainties from 0.6×10⁻⁶ to 1.2×10⁻⁴

Reduced calibration time and improved reliability

Eliminated the need for multiple standards during calibration

Abstract

At National Institute of Metrological Research (INRIM), an automated setup to calibrate DC Voltage generators, mainly top-level calibrators from 1 mV to 1 kV has been developed. The heart of the setup is an INRIM-built automated fixed ratios DC Voltage divider. The significant achievement of this setup is the possibility to interconnect the divider, a DMM characterized in linearity, a DC Voltage Standard and a DC Voltage generator under calibration and automatically to manage the calibration process. This calibration method allows to save a lot of time, to improve the reliability and to increase the accuracy of the calibration of generators. The relative uncertainties of the system span from 0.6x10-6 to 1.2x10-4 improving the previous capabilities of the INRIM laboratory for calibration of programmable multifunction instruments. In addition, this system allows to avoid the employment of several Standards (some of them still manually operating) carrying out the entire process without changing the setup configuration and without the presence of operators. The concept of this setup can be transferred to secondary high-level electrical calibration Laboratories that could be consider it useful for their calibration activities.