26Calibrate the PsychrometerThe Stem Psychrometer MUST BE calibrated before each installation.The calibration employs a 6 point measurement protocol using NaCl solutions ofknown molalities. The calibration must be done under isothermal conditions at acontrolled temperature of 25 °C to generate a specific slope and intercept thatcharacterises the specific response of the individual thermocouples. A detailedcalibration function is provided within the PSY1 software that can be used togenerate and automatically load your new calibration into the PSY1 firmware.Watch the videos – Stem Psychrometer Calibration SP08, SP09 and SP10 fordetails. The calibration is applied and tracked via the four-digit serial numberof the psychrometer chamber and will remain in the instrument in non-volatileRAM until changed by the user. This number must be manually entered into theinstrument firmware. Watch the video Stem Psychrometer Calibration FunctionDemo for details.ICT InternationalEnabling better global research outcomes in soil, plant & environmental monitoring.