Electrical conductivity is the capacity of a material to convey electric current in the presence of an electrical potential. It is an inherent characteristic determined by the existence of charge carriers like electrons or ions and their diffusion in the material. Conductivity measurement finds wide application in laboratory and industrial settings to measure the quality of water, chemicals semi-conductors and metallic materials. The method provides a fast and non-destructive method of measuring the change in composition concentration and behavior dependent on temperature. With the need to have accurate control of the characteristics of materials, conductivity measurement has become a necessary element of daily testing and research processes in modern industries.
Principle and Methodology
The law of measurement of electrical conductivity is pegged on the law of Ohm that relates current, voltage, and resistance. The opposite of resistivity is conductivity, which is determined by the quantity of the carriers of charge and their mobility in the substance. Dissolved ions tend to control conduction in liquids, but in solids, it is due to the electron structure and defects. The measurement is normally done by the use of conductivity cells with electrodes that are connected to a conductivity meter. To eliminate polarization effects and the resultant current flow, an alternative current is then applied, and the current is measured. The tool then measures conductivity by accounting for the known cell constant, measuring resistance, and adjusting it for changes in temperature.
Instrumentation and Calibration Instrument
To measure conductivity well, the instruments have to be designed in a way that they can be calibrated regularly. Conductivity meters come in various forms of simple handheld meters to high-sensitivity and automated temperature-compensated benchtop systems. The electrodes to be used are chosen depending on the anticipated range of conductivity and the sample to be used. Calibration is done with standard solutions whose conductivity is known so as to provide reliability in measurements. To avoid fouls and drift that may lead to inaccuracy, probes should be well cleaned and maintained.
Industrial Use
The measurement of electrical conductivity is very popular in various industries. In water treatment, it is used to determine purity, salinity, and the total dissolved solids. In chemical production, it can be used to regulate the amount of reaction and solution concentration. Conductivity data are used in electronics and semiconductor industries to define the properties of materials and provide a universal electrical behavior. In food and beverage manufacturing, conductivity is used to monitor the cleaning process and the composition of products.
Importance
The significance of measuring the electrical conductivity is the fact that it is fast and reliable. It offers instant results on the quality of materials and the condition of the processes without having to spend so much money on preparing samples. Continuous conductivity checking helps to ensure quality, save waste, and optimize the processes. With the ever-growing advancement of industries towards automation and strict control of the electrical conductivity, the measurement of this conductivity is a critical instrument in the assurance of safety performance and product integrity.
