The Project

The VmicroC project developed a sensor string that combined seven sensors for measuring temperatures in grape vine canopies. Measurements were made at -0.2, 0, 0.4, 0.8, 1.0, 1.2 and 1.8 metres.

Each sensor was calibrated to +/- 0.1 °C. To do this they were placed in a stainless steel double walled enclosure filled with 1500mL of mineral oil chilled to -15 °C along with a reference thermometer. The oil was forced across the sensors and reference thermometer using two 50 millimetre computer case fans. These fans slowly raised the temperature of the oil to approximately 60 °C over several hours. A linear correction factor for each sensor was derived by comparing its values to those of the reference thermometer. A total of 44 sensors could be calibrated in a single run.