Rationalizing Null Readings at Low Levels

This Application Guide discusses the problems encountered when comparing nulls, especially nulls made in the micro-volt and nano-volt regions, between two null meters. Frequently minor differences between two different null meters, the minor differences between instrumentation setups and other environmental issues contribute to those differences. This Application Guide is written to help a null meter user rationalize the differences and to take corrective actions, where possible, to reduce the differences between readings.