Factory Calibration:
A standard factory calibration would guaranty the accuracy of 88% or better (usually in mid 90’s) and the offset of 0.85pH of fewer for a brand new sensor.
This means that the sensor have to calibrated if you need a precise and accurate output. If you like to use the sensor for detecting ammonia leakage into fresh water of mixtures between water and ethanol/methanol/glycol a calibration is normally not needed. If you like to use the sensor in other brines with a higher pH value or in NaCl brines, we strongly recommend a calibration. The reason is that an ammonia leakage will not impact the pH value as much in these fluids, because they act as a buffer.
Using 4mA = 0pH and 20mA = 14pH, the worst case scenario (88% accuracy and max allowed offset) may equate to roughly speaking ±1.0 pH assuming no calibration is done at the installation site.