Typical Techniques for Calibration of Accurate Digital Thermometers
1. Preparation before calibration
If the thermometer has a calibration function, set its working mode to the calibration mode before turning on the machine, and then connect the first-class standard resistors at constant temperature in the thermostat to the thermometer according to the range of the thermometer, then turn it on, and wait for the temperature to be measured. After the meter is stable, input the value in the standard resistance verification certificate into the thermometer, and then shut down after stabilization; set the working mode of the thermometer to the measurement mode, and turn it on to prepare for calibration. Start the machine and input and store the relevant data in the platinum resistance thermometer certificate as required.
2. Selection of Calibration Points
Generally choose 25Ω, 100Ω measurement points, and other measurement values can be selected according to needs.
3. Calibration
Connect the standard resistance to the thermometer according to the range of the thermometer, and read the resistance value of the thermometer after the thermometer is stable.
4. Calibration method
Use the fixed-point method or the comparison method. When using the comparison method to calibrate, insert the standard platinum resistance thermometer and the sensor of the thermometer to be calibrated into the constant temperature bath, and start reading the readings of the standard thermometer and the thermometer to be calibrated after the temperature is stable, and then read again at intervals of 1 to 2 minutes. 2 times in total.
