Precision DC Measurements Below 1 ppm: How Automation Improves Accuracy

Thu 30.07.2026

How can voltage, resistance, and temperature be measured with uncertainties below 1 ppm? This application note presents methods developed in collaboration with leading metrology laboratories, using low-thermal switching systems to minimize unwanted thermoelectric effects. It demonstrates that well-designed automation not only reduces labor but also significantly improves measurement accuracy, repeatability, and overall data quality.

Precision DC Measurements Below 1 ppm: Automation as a Tool for Higher Accuracy

This application note summarizes experience gained through collaboration with leading metrology laboratories around the world and presents modern approaches to automated low-level DC measurements.

It focuses on achieving exceptionally low measurement uncertainties in voltage, resistance, and temperature measurements-at levels better than 1 ppm.

A key topic is the use of Low Thermal Switching systems, which minimize unwanted thermoelectric effects generated at junctions between dissimilar metals. These seemingly insignificant voltage offsets are often the limiting factor in the most demanding laboratory measurements.The publication demonstrates that automation is not merely a means of reducing labor and increasing productivity. A properly designed automated measurement system can significantly reduce human influence, ensure consistent measurement procedures, improve repeatability, and ultimately achieve higher accuracy than manual methods.

Practical examples illustrate techniques used in the calibration of voltage standards, precision resistors, and temperature sensors.For metrology laboratories, calibration facilities, and manufacturers of precision instrumentation, this document provides a valuable collection of proven practices that help push DC measurement accuracy to the limits of current technological capabilities. 

Link to the application note: Application Notes: Precision Measurements with Low Therma