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ph_accuracy [27/02/2019 07:36]
pieter [The pH buffers]
ph_accuracy [13/03/2019 09:59]
pieter [The pH meter]
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   * the measurement __linearity__ between and outside the calibration points.   * the measurement __linearity__ between and outside the calibration points.
  
-As example, a pH meter with an accuracy given as (0.2%+1 digit) and a resolution of 0.01 pH. It depends on the reproducibility at the calibration points (± 0.01, 1 digit) and the linearity between and outside the calibration points (0.2%). When a calibration is done at pH 7.00 and pH 4.00, the device error at these same points is ±0.01 pH. For a measurement at 5.50 pH , the device error is (1.50 pH * 0.002) ± 0.01.+As example, a pH meter with an accuracy given as (0.2%+1 digit) and a resolution of 0.01 pH. It depends on the reproducibility at the calibration points (± 0.01, 1 digit) and the linearity between and outside the calibration points (0.2%). When a calibration is done at pH 7.00 and pH 4.00, the device error at these same points is ±0.01 pH. For a measurement at 5.50 pH , the device error is ((1.50 * 0.002) 0.01) = 0.013 pH.
  
 ==== The pH electrode ==== ==== The pH electrode ====
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 Check the accuracy of the pH buffers to know the possible measurement errors. Measuring between 2 buffers, used for the calibration, with an accuracy of 0.02 pH will introduce a measurement error of 0.04 pH. Check the accuracy of the pH buffers to know the possible measurement errors. Measuring between 2 buffers, used for the calibration, with an accuracy of 0.02 pH will introduce a measurement error of 0.04 pH.
  
-Also follow the [[ph_measurement_tips#good_measurement_practices |Good Measurement Practices]] to make sure the calibration is done in the best conditions as possible. Don't rush the calibration to make sure all values are correctly registered by the meter.+==== The user ==== 
 +Follow the [[ph_measurement_tips#good_measurement_practices |Good Measurement Practices]] to make sure the calibration is done in the best conditions as possible. Don't rush the calibration to make sure all values are correctly registered by the meter.
  
  
ph_accuracy.txt · Last modified: 13/03/2019 09:59 by pieter