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Depending on the pH sensor, most of them shouldn’t be stored in de-ionized or demineralized water because of it shortening the lifespan of the sensor [4].

Factors affecting accuracy and performance of reference electrodes

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The length of time between cleaning and calibration depends on process conditions and the user's accuracy and stability expectations [1].

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Industrial pH sensors

Industrial-grade pH sensors are typically mounted on special mounts to allow wider range of use in different applications [3]. Different mounts give option for installing the sensor submerged, so that liquid flows through it or so that they are inserted into the liquid when needed. Instruction manuals on this kind of sensors provide various different values and specifications to help determine operability in process conditions. Typically at least measuring range, sensitivity, stability, temperature range, pressure range and weight are quickly and easily obtainable from manuals. Sometimes industrial sensors contain preamplifiers that are installed as close to the sensor unit itself for easier calibration work and also cables of these industrial type sensors are well protected with signal shielding, chemical protection etc. [3].

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Picture 3 Cable of industrial pH sensor

References

1. http://www.sensorland.com/HowPage037.html

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