pH and NH3 probe calibration

Normal systems for continously measuring PH require calibration.

Calibration should always be done using more than one point to ensure accuracy.

Remember if you have a probe it will only be as good as the calibration fluids used to set it and these can greatly vary.

Good quality calibration fluids should be used and these can be expensive. Also PH probes should be changed anually as there response and accuracy will change with age.

PH calibration is a place that error often is introduced in as the various steps are followed by the user.

Low cost pH probes can be very inaccurate in low buffered solution, this is due to the fact that a certain amount of ionic strength is required to create a reading in the electrode. For this reason different equations should be used on the same probe depending upon ionic strength.

NH3 cannot be calibrated as all calibaration fluids would be uinstable when stored due to off gassing.

With a seneye device you should not need to use calibration as the replacement seneye+ slide does this.