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In the use of such instruments, it is common to observe that once the operator has completed the sample testing and turned off the power supply, there is a lack of awareness regarding the fact that instrument maintenance and care are closely related to the accuracy of measurements. So, how should one address electrode contamination and maintenance in moisture analyzers? The electrodes are key components of moisture analyzers, and contamination on their surface can directly lead to a decrease in sensitivity. Some electrodes are used for analyzing oily samples over extended periods of time, and when their surfaces become contaminated with oil, their sensitivity drops, which results in delayed detection of the endpoint. This leads to an excess of Karl Fischer reagent and a darker color of the solution at the endpoint; in such cases, it is necessary to clean the electrodes. Although contaminants on the electrodes are not visible to the naked eye, a sluggish reaction can be observed, which directly affects the accuracy of the measurements. Therefore, the electrodes must be cleaned after being used for a period of time, but a considerable number of operators fail to take this into account. When the sensitivity decreases and the electrodes are severely contaminated. A piece of paper dipped in acetone can be used to wipe the electrodes, but care must be taken, and it is necessary to wait until the acetone has completely evaporated before using it. Alternatively, immerse the electrode in dilute nitric acid solution for 24 hours, then remove it, rinse it with clean water, and wipe it dry with filter paper. The electrode can also be cleaned with a potassium dichromate solution for 1 minute to activate it. In special cases, such as when samples are waiting to be analyzed and there is no time to clean the electrodes, urgent measures can be taken to address electrode contamination. Gently rub the ends of the electrodes with very fine sandpaper; after wiping them clean with filter paper, the effect will be visible. If the instrument is not used for a period of time, all of the Karl Fischer reagent in the pump tubing and fluid pathways should be drained to prevent blockages in the pipelines due to crystallization caused by the evaporation of the reagent; similarly, the Karl Fischer reagent in the reaction vessel should also be drained, and the electrodes should be cleaned.