NTC calibration and multiple temperature sensors: Difference between revisions
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Revision as of 15:42, 6 September 2023
Introduction
Calibration of NTC sensors and different
NTC
Note that the temperature of the sensor rises when the current supplies through the resistor. The NTC is nonlinear; see below Calibration.
Negative Temperature Coefficient, NTCLE100E3101JB0 or similar (MF52B NTC Thermistor). The NTC is connected in series with a "shunt" resistor Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle R_1} , see Measurement of resistors: voltage divider. Usually Failed to parse (Conversion error. Server ("https://wikimedia.org/api/rest_") reported: "Cannot get mml. Server problem."): {\displaystyle R_{1}=10kOhms} is used. The total resistance of the circuit is Failed to parse (Conversion error. Server ("https://wikimedia.org/api/rest_") reported: "Cannot get mml. Server problem."): {\displaystyle R=R_{1}+R_{NTC}} , which gives
Calibrating: Steinhart-Hart Equation
A nonlinear Steinhart-Hart equation is widely used
Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \frac 1T = A + B \ln(Rt) + C (\ln (Rt))^3 }
Calibrating using known datapoints
Though the NTC sensor is nonlinear, locally it will be linear. Thus by using some known datapoints the temperature can be estimated.