The recommended way to calibrate and adjust Vaisala GMP250 Series CO2 probes is using Vaisala's calibration service, Vaisala Insight PC software, or a compatible handheld meter. However, some users may have a need to implement a solution based on the Modbus protocol. This technical note provides the necessary information to operate the calibration sequence using the Modbus protocol, as well as some additional information about matters affecting the quality of the resulting calibration.
Using the Modbus protocol, you can calibrate and adjust the CO2 measurement in 1 or 2 points. Before carrying out calibration and adjustment with Modbus, review the adjustment requirements information in Adjustment requirements.