Teeb pH meeter kasutab viga ilma esimene kalibreerimine?
1. üks punkt kalibreerimine happesus meeter
Any pH meter must be kalibreeritud koos a pH standard lahus enne mõõtmine the pH value of the sample. For samples with a measurement accuracy below {{{{0}}.1pH, the instrument can be adjusted with a one-point accurate method. Üldiselt, pH6.86} or pH7. 00} standard buffer. Some instruments have an accuracy of only 0}.2pH or 0.lpH, Niisiis The Instrument Only Has A ¨Positioning¨ Adjustment nupp. The specific operation steps are as follows:
(1) mõõt temperatuur standard puhver lahus, kontroll tabel to määra the pHs value at the temperature, and adjust the temperature compensation nupp to the the temperature.
(2) loputada elektrood puhta veega ja loksutada kuivatada.
(3) kastmine elektrood sisse puhvrik lahus ja loksutamine see ja koht see ikka. pärast lugemine on stabiilne, reguleerimine positsioneerimine nupp to mark mõõtevahend ekraan pH väärtus of standard lahus.
(4) välja välja elektrood, loputus ja kuiv see.
(5) mõõt proov temperatuur, ja reguleerimine temperatuur kompensatsioon nupp pH meeter to temperatuur väärtus
2. kahepunktiline kalibreerimine happesus meeter
For precision pH meters, in addition to ¨positioning¨ and ¨temperature compensation¨ adjustments, there is also an electrode ¨slope¨ adjustment, which requires two standard buffer solutions for calibration. Üldiselt, pH6.86} or pH7.00} is used for ¨positioning¨ calibration first, and then according to the acid-base condition of the test solution, pH4.% 7b{6}} (happeline) or pH9.18 ja pHI0.0l (leeliseline) puhver lahus is selected for ¨slope¨ Correction. The specific operation steps are:
(1) Puhas ja kuiv the elektrood, kastmine in pH6.86} or pH7.00 standard lahus, ja koht temperatuur kompensatsioon nupp of the instrument at temperatuur of the solution. After the displayed value is stable, adjust the positioning nupp to make the instrument display the pHs value of the standard solution.
(2) Take out the electrode, wash and dry it, and sukelda it in the second standard solution. After the displayed value is stable, adjust the slope nupp of the instrument so that the displayed value of the instrument is the pHs value of the second standard solution.
(3) Take out the electrode, wash it and dry it, then sukel it in pH6.86} or pH7.00} buffer solution. If the error exceeds 0.02pH, repeat steps (1) and (2) until the correct pHs can be display in the two standard solutions without adjusting the nupp.
(4) Take out the electrode and dry it, adjust the pH temperature compensation nupp to the temperature of the sample solution, sukel the electrode in the sample solution, shake it and place it still, and the reading will display after stabilization.
3. Kolmas punkt kalibreerimine of the pH meeter
No mateeria mis kind of pH meeter, the point of pH{{{{{{}}}} must be calibrated, and the point of pH=7 must be calibrated first during the two-point calibration. When doing calibration, start from 7.0, and the selected standard solution is related to the pH value of the solution to be measured, so that the pH value of the solution can fall within the calibrated pH range. Üldiselt, kaks punkti saab kasutada et vastata the requirements. If the requirements are very high, the third point should be considered. Some instruments can calibrate three points, and there is an optional mode, what can be used directly. For some that don't, two-point two-point proofreading is general used, that is, proofreading twice.
