Calibration of DC Voltage Dividers up to 100 kV

A system for calibrating dc voltage dividers up to 100 kV with an uncertainty (1α) of the order of 5 X 10-6 is described. The main component is a 200 MΩ guarded resistive device rated for the maximum voltage, forced-air cooled, and made up of 100 individually screened 2 MΩ resistors connected in series. An arrangement for series-to-parallel connection of the 100 resistors is provided in order to evaluate the total series resistance and the self-heating effect at full current and low voltage.