Introduction: Every ANB transducer contains a built-in thermistor for temperature monitoring, which plays a crucial role in our internal algorithms for calculating pH. Since pH measurement requires a temperature accuracy of just ±0.2°C, our sensors are designed to meet this precision reliably.

Aim: To assess the accuracy and reproducibility of our thermistors, three sensors were run in continuous mode alongside two temperature loggers in a controlled tank environment, where the temperature was gradually increased from approximately 5°C to 35°C.


Results: Throughout the experiment, all three ANB sensors closely tracked temperature changes in alignment with the two external loggers. These results demonstrate the sensors’ accuracy and consistency, confirming their reliability for precise temperature monitoring across various environmental conditions.


Aim: To assess the T90 of the sensor’s temperature measurement, two AQ5 sensors were ran in a temperature controlled tank at 1.5°C and then switched to a second tank at 29.1°C, along with two external temperature probes.


Results: Both sensors demonstrated excellent responsiveness, with the sensors reaching the final temperature in approximately 9 minutes, with T90 values (time taken for each sensor to reach 90% of the final temperature) of 3m 8s for Sensor 1 and 3m 45s for Sensor 2.


Aim: To assess the accuracy, reproducibility, and potential variation in temperature measurements across sensors with different transducers, four sensors with three different transducer combinations were immersed in tanks at temperatures of 7 °C, 18 °C and 27 °C. Their temperature output was compared to an external temperature probe.

Results: On average, the sensors deviated by 0.12 °C, with a standard deviation of 0.09 °C, suggesting moderate variability across measurements. Half of the deviations were within 0.10 °C, and 75% of the measurements were within 0.14 °C. These findings demonstrate that the transducers can be moved between sensors without requiring additional temperature calibration, highlighting their versatility and reliability. The temperature measurements from the sensors are highly accurate, with the worst-case deviation from the external probe being 0.38 °C.