To Consort website  |  Print page

User Tools

Site Tools


ph_calibration_requirement

Differences

This shows you the differences between two versions of the page.

Link to this comparison view

Both sides previous revision Previous revision
Next revision
Previous revision
ph_calibration_requirement [24/10/2018 07:06]
pieter
ph_calibration_requirement [24/10/2018 07:21]
pieter [Simply check]
Line 2: Line 2:
 This process will give information on how frequently calibration/​maintenance/​replacement of the sensor needs to be done in regard to the frequency of use and the sample matrix. This process will give information on how frequently calibration/​maintenance/​replacement of the sensor needs to be done in regard to the frequency of use and the sample matrix.
  
-=== Accuracy ===+==== Accuracy ​====
 The frequency that you should calibrate your pH electrode depends on many factors such as the type of your test samples, performance of electrodes, and the requirement of the accuracy. For High-Accuracy measurements (≤ ±0.02pH), the electrode should be calibrated before test every time; For general-accuracy Measurements (≥±0.1pH),​ once calibrated, the electrode can be used for about a week or longer. ​ The frequency that you should calibrate your pH electrode depends on many factors such as the type of your test samples, performance of electrodes, and the requirement of the accuracy. For High-Accuracy measurements (≤ ±0.02pH), the electrode should be calibrated before test every time; For general-accuracy Measurements (≥±0.1pH),​ once calibrated, the electrode can be used for about a week or longer. ​
  
Line 12: Line 12:
   * There is a big difference between the temperature of the test sample and the temperature of the buffer solution that is used in the last calibration.   * There is a big difference between the temperature of the test sample and the temperature of the buffer solution that is used in the last calibration.
  
-=== Frequency ===+==== Frequency ​====
 Typically, pH probes and many conductivity probes are calibrated at the start of each 8 hour shift, but this can vary depending on application. Typically, pH probes and many conductivity probes are calibrated at the start of each 8 hour shift, but this can vary depending on application.
  
Line 23: Line 23:
   * The customer experience in regard to samples and application.   * The customer experience in regard to samples and application.
  
-=== Simply ​check ===+==== Simple ​check ====
 There is a simple way to quickly check if your pH meter needs a calibration at the moment. All you need to do is dip the pH probe into the calibration standard solutions such as pH 4.00 or pH 7.00, and see if the measurements have a big difference to the standard value. For most applications (if not for scientific research), if the difference is within 0.05 pH, for example the meter reads 6.97 in 7.00 solution or 4.03 in 4.00 solution, then it means the meter is in good condition and a calibration is not a must at the point. If the difference is over 0.05 pH, for example the meter reads 6.92 in 7.00 or 4.08 in 4.00, then a calibration is necessary and highly recommended before testing. There is a simple way to quickly check if your pH meter needs a calibration at the moment. All you need to do is dip the pH probe into the calibration standard solutions such as pH 4.00 or pH 7.00, and see if the measurements have a big difference to the standard value. For most applications (if not for scientific research), if the difference is within 0.05 pH, for example the meter reads 6.97 in 7.00 solution or 4.03 in 4.00 solution, then it means the meter is in good condition and a calibration is not a must at the point. If the difference is over 0.05 pH, for example the meter reads 6.92 in 7.00 or 4.08 in 4.00, then a calibration is necessary and highly recommended before testing.
  
-=== General advice ===+==== General advice ​====
 In all cases the calibration frequency is a customer experience based decision linked to the sample type measured and the measurement frequency. Some generic advise and recommendations for use would be: In all cases the calibration frequency is a customer experience based decision linked to the sample type measured and the measurement frequency. Some generic advise and recommendations for use would be:
  
ph_calibration_requirement.txt · Last modified: 24/10/2018 07:21 by pieter