What should I do if the equilibrium drift of the Coulomb method moisture meter keeps increasing?

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I. Check and replace reagents ✔ Expired or near-expiry reagents: The shelf life of reagents in China is generally between six months and one year; using reagents that have passed their expiration date or are near it can lead to problems such as slow equilibrium establishment and difficulty in achieving equilibrium. At this point, fresh reagents should be replaced. ✔ Decreased electrolyte efficiency: When the electrolyte efficiency drops to 60% or below, balance issues also tend to occur. A fresh electrolyte also needs to be replaced. II. Controlling environmental humidity ✔ Impact of humidity: The Coulomb method is used to measure trace amounts of moisture, and high environmental humidity can make it difficult to achieve equilibrium. ✔ Control measures: Apply silicone grease to all connections of the reaction cup to reduce the impact of humidity on the environment inside the cup ； Control the humidity of the environment by using a dedicated dehumidifier or an air conditioner with a dehumidification function ； Where conditions permit, a dedicated glove box or a drying room can also be provided. III. Clean and dry the reaction cup and electrodes ✔ Water on the cup walls: Water on the cup walls or at the junction where the cup walls meet the electrodes can lead to difficulties in achieving equilibrium. ✔ Cleaning and drying: Remove components such as electrodes and drying tubes, pour out the electrolyte, clean the cup and electrodes with anhydrous ethanol, and dry the reaction cup and all components at 50–60°C. IV. Check and replace the carrier gas desiccant or use high-purity carrier gas. ✔ Excessive moisture in the carrier gas: When using carrier gas, if its moisture content is too high, it can also cause the instrument to remain unbalanced for an extended period, with the electrolysis values staying at high levels. ✔ Solution: Replace the desiccant used for purifying the carrier gas, or use a high-purity carrier gas (N2 with a purity of 99.99% or higher). V. Check and repair electrode failures or incorrect parameter settings. ✔ Electrode failures: Issues such as damaged electrodes, broken platinum wires, or damaged wires can all affect the balance of the instrument. ✔ Incorrect parameter setting: Check whether the parameter settings of the instrument are correct; if there are any errors, adjust them promptly. VI. Other inspections and maintenance ✔ System sealing: Check whether the system is well-sealed, and determine if components such as molecular sieves, sampling silicone gaskets, and sealing rings need to be replaced. ✔ Desiccant replacement: Regularly replace the desiccant in the desiccation tube on the reaction cup. Molecular sieves can be regenerated: bake at 200-300°C for 24 hours; it is recommended not to reuse them more than 5 times.