New Approach in Wide Range Conductivity Measurement with Planar Sensor

New Approach in Wide Range Conductivity Measurement with Planar Sensor

Paper in proceedings (conference paper)

This paper contributes to the field of precise electrolytic conductivity measurements with planar sensors. This novel measuring method was suggested for measurement with comb-like thick-film electrodes. Correction characteristics over a wide range of a specific conductivities were determined from an interface impedance characterisation of the thick-film electrodes. The cell constant strongly depends on the frequency and conductivity of solutions. A local minimum of the imaginary part of the interface impedance is used for corrections to get linear responses. In this minimum a ridge frequency and cell constant were determined for each measured conductivity. An iteration mode of measurements was suggested to exactly measure the conductivity in the ridge frequency in order to achieve a highly accurate response. An implementation of this method as a microcontroller application can used to build-up microsystems for precise conductivity measurements in concentration ranges from 10-6 to 1 M without cell replacement.

This paper contributes to the field of precise electrolytic conductivity measurements with planar sensors. This novel measuring method was suggested for measurement with comb-like thick-film electrodes. Correction characteristics over a wide range of a specific conductivities were determined from an interface impedance characterisation of the thick-film electrodes. The cell constant strongly depends on the frequency and conductivity of solutions. A local minimum of the imaginary part of the interface impedance is used for corrections to get linear responses. In this minimum a ridge frequency and cell constant were determined for each measured conductivity. An iteration mode of measurements was suggested to exactly measure the conductivity in the ridge frequency in order to achieve a highly accurate response. An implementation of this method as a microcontroller application can used to build-up microsystems for precise conductivity measurements in concentration ranges from 10-6 to 1 M without cell replacement.

IDEs, electrolytic conductivity, iterative measurement

HUBÁLEK, J., KREJČÍ, J., KOLAŘÍK, V.

18.12.2002

FEKT VUT v Brně

Ing. Z. Novotny, Brno

80-214-2217-3

Socrates Workshop 2002 - Proceedings. Intensive Training Programme in Electronic System Design. Chania, Crete (Greece)

112

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