Why Automating pH Measurement is Important

Automation of pH allows for a more consistent recording of measurements undertaken. However, it is important that the automation instrument has the means to accurately control the precision of the pH test been performed. Stirrer speeds, the type of stirrer used, electrode washing and pH meter settings all play a key role in accuracy and precision of any soil or water pH test. Studies have found that automated pH measurement is far more accurate than a manual measurement as the manual method usually involves using the pH electrode to stir the medium. This results in loss of sensitivity on the pH electrode junction (glass bulb) as the abrasive nature of the stirring in this manner slowly wears away the thin wall of the glass bulb.

pH is a measure of acidity or alkalinity in either a soil or liquid medium. The correct pH in either soil or water allows a process to happen more effectively to achieve an end goal. In the case of soil, it is important for a plant to be in the correct pH zone for it to grow and produce quality product. The correct pH helps the plant to absorb any nutrients that are present in the soil. Water and liquids on the other hand, the pH may need to be adjusted to suit a specific need.

Automated pH Meter Controls

Automated pH meter controls are far superior than that of manual pH meter testing as an operator will “push” the read button they think the pH electrode is stable. This may not be the case though. Some laboratories still use this method of reading and recording pH results. When automated pH meter controls are employed, the meter pH electrode stability, number of readings and statistical controls are calculated on the fly. This means much stricter quality assurance measures and better pH meter recordings.

Manual Stirring of pH Samples

When pH is typically measured, the sample usually is stirred to keep the soil in suspension and to get a even distribution of hydrogen ion across the sensor. By manually stirring, an operator can suffer the effects of bad ergonomics causing operator fatigue. With an automated pH measurement system, the stirring is done automatically. Another advantage of automation is that an operator can define when and how the stirrers come, for how long and at what speed.

The Importance of pH Electrode Washing

pH automation also provides for better cross-contamination elimination as the automated pH tester provides functions of when and how to wash the pH electrodes. An automated power wash system, such as the ones used on the Labfit automated pH robots provide superior pH electrode cleaning. This means that from muddy soils types the washed pH electrode is clean and free of foreign matter. Washing controls cleanliness of pH electrodes and how much carry over or cross contamination between samples.