The construction of a DC high voltage precision divider

A precise DC high-voltage divider was designed and constructed for use as a standard. The ratio of the divider for precise measurement must be known accurately independent of voltage and time. The changes in total resistance of a divider with voltage and time should be considered before design and construction. The divider consists of 100 wire-wound resistors with a total resistance of about 100 MΩ as the high-voltage arm and one wire-wound resistor with resistance of 100 kΩ as the low-voltage arm. The high voltage and ground electrodes were designed to prevent electric field concentration and corona formation at high voltages. A current measuring instrument with 6.5 digit resolution was developed to allow comparison of entering and existing currents for detection of current leakage. Considering the sources of error, a relative uncertainty of 66 ppm (parts per million) was obtained with coverage factor k = 2 for the constructed DC high-voltage divider.