pH probes and sensors have a difficult time measuring in low-conductivity water found in power plant cycle chemistry and microelectronics manufacturing applications. Until recently this required a measurement sensor, a reference sensor, a temperature sensor and a flow bowl. This is no longer necessary with the right selection of pure water pH electrodes.
pH/ORP Frequently Asked Questions
How often should I calibrate my pH sensor?
The calibration interval needed for pH is highly application-dependent. The more uniform process conditions are (temperature, pressure, composition, freedom from coating, etc.), the more stable a pH sensor will be and the longer the calibration interval may be. Most pH installations calibrate between once a week and once a month but shorter or longer intervals may be appropriate based on experience. It is a good practice to begin by calibrating frequently and then gradually go to longer intervals, as stability in the installation and accuracy requirements allow.
What is the shelf life of pH and ORP (redox) sensors?
If a pH or ORP sensor is stored at normal room temperature with its original storage cap and solution in place on the end of the electrode, it can last well over a year with no degradation in performance. If the storage solution is allowed to dry or leaks out due to storage at high temperatures, freezing or other causes, the life may be reduced significantly.