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E-mail
chinainfo@fesks.com.cn
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Phone
13795339399
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Address
2nd Floor, Building A, No. 135 Yinyu Road, Jiading District, Shanghai
Fisker Instruments (Shanghai) Co., Ltd
Guidelines for Calibration Cycle and Method of Imported PH Meter
Date: 2025-08-18Read: 0
Imported pH meterAs a high-precision water quality analysis instrument, its measurement accuracy relies on a standardized calibration process. Scientifically setting calibration cycles and strictly implementing calibration methods are the core links to ensure the reliability of detection data.
1、 Calibration cycle setting
The calibration cycle should be dynamically adjusted according to the frequency of use and environmental conditions: equipment used continuously every day should be calibrated every 24 hours; Instruments used intermittently are recommended to be calibrated before each use; If used for the detection of highly polluted or highly corrosive samples, it needs to be shortened to once every 8 hours for calibration. A pH meter that has been idle for a long time must be calibrated before being put back into use, and maintenance calibration must be performed once a month to maintain electrode activity.
2、 Preparation before calibration
Prepare three standard buffer solutions (commonly pH 4.00, 6.86, 9.18) to ensure they are within their expiration date and sealed properly. Before calibration, remove the electrode from the protective solution, rinse it three times with deionized water, and dry the surface moisture with lint free paper. At the same time, check whether the power cord connection of the instrument is stable, whether the display screen is displaying normally, and the ambient temperature should be controlled at 20-25 ℃ to avoid airflow and electromagnetic interference.
3、 Calibration operation steps
Two point calibration method: First immerse the electrode in a pH 6.86 standard solution, stir for 10 seconds, and then let it stand. After the reading stabilizes, press the "Calibration" button to confirm; Repeat the operation with pH 4.00 (acidic range) or pH 9.18 (alkaline range) standard solution in sequence, and the instrument will automatically complete the slope correction.
Three point calibration method: suitable for wide range detection requirements, adding midpoint calibration on the basis of two-point calibration to ensure full range accuracy. After calibration is completed, a new standard solution should be used for verification, and the error should be ≤ ± 0.02pH
4、 Precautions
The standard buffer solution should be protected from direct sunlight and the bottle cap should be tightly closed immediately after each use to prevent CO ₂ from entering and affecting the concentration. When the electrode is immersed in the solution, it is necessary to ensure that the bubbles are submerged and do not touch the container wall. If there is a reading drift during the calibration process, the electrode should be checked for aging or contamination, and replaced if necessary. Calibration data should be recorded in detail, including date, batch number of standard solution, calibration results, and operator, and archived for at least 1 year.
Strictly following this guide for calibration can fully leverage its potentialImported pH meterThe accuracy advantage provides reliable data support for water quality analysis.