Temperature, Measurement, Calibration, Error, Response
The work investigated the responses of measuring and calibrating the temperature in the range of 30 to 60°C using a setup of TH1. The setup was configured with an ice flask, sensor installing unit, an electrical console, and a regulating bath which can withstand temperatures in the range of 0°C to 100°C. Various sensors such as industrial platinum resistance thermometer PT100IND, type K thermocouple, and a thermistor were installed. The setup was configured with highly accurate reference sensors of platinum resistance device PT100, with NAMAS calibration certificate, and temperature with linearized output. Extra reference sensors were installed such as bi-metallic and liquid-in-glass thermometers to ensure high accuracy in measuring and calibrating data. The experimental data revealed that the PT100IND resistance changed linearly with temperature. The calibration error of PT100IND, according to the temperature data, reached a maximum value of less than 1.60%. According to the temperature scale of ITS-90, the standard parameters of calibration equation of Callendar-van Dusen for PT100IND provided errors of less than 5.5% and 3.2% respectively. The type K thermocouple delivered a linear change in output with highly stable temperature response. According to NIST data, the calibration error for the thermocouple reached a maximum value of less than 0.98%. The thermistor resistance revealed weak and late response at low temperature, but its sensitivity improved with increasing temperature. The calibration error according to experimental data and the Steinhart-Hart equation for the thermistor sensor was less than 0.30%.