Electrolytic conductivity - a new field of activities at PTB

摘要

During the last two years first steps were taken at PTB to establish a national standard for electrolytic conductivity. A primary cell enables measurements over a wide range of conductivities between 2 μS cm~(-1) ...10 mS cm~(-1). Side effects caused by inhomogeneous electric field distribution are eliminated by altering the electrode spacing during the measurement. Traceability to the SI has been achieved through calibration of the cell geometry and through traceable impedance and temperature measurements. The contribution describes the measurement procedure and first experience including the sources of uncertainty in the calibration of primary potassium chloride reference solutions. Further, the intended traceability chain for electrolytic conductivity in Germany is introduced.