# A novel ppm-precise absolute calibration method for precision high-voltage dividers

## TL;DR

This paper introduces a new absolute calibration method for high-voltage dividers that achieves ppm-level accuracy using commercial equipment, enabling broader application outside specialized metrology institutes.

## Contribution

A novel differential scale factor calibration method that allows ppm-precise measurements of high-voltage dividers with commercial tools outside metrology labs.

## Key findings

- Reproducible measurements up to 35 kV with below 1e-6 uncertainty.
- Method applicable outside metrology institutes.
- Enables linearity testing of high-voltage dividers across various applications.

## Abstract

The most common method to measure direct current high voltage (HV) down to the ppm-level is to use resistive high-voltage dividers. Such devices scale the HV into a range where it can be compared with precision digital voltmeters to reference voltages sources, which can be traced back to Josephson voltage standards. So far the calibration of the scale factors of HV dividers for voltages above 1~kV could only be done at metrology institutes and sometimes involves round-robin tests among several institutions to get reliable results. Here we present a novel absolute calibration method based on the measurement of a differential scale factor, which can be performed with commercial equipment and outside metrology institutes. We demonstrate that reproducible measurements up to 35~kV can be performed with relative uncertainties below $1\cdot10^{-6}$. This method is not restricted to metrology institutes and offers the possibility to determine the linearity of high-voltage dividers for a wide range of applications.