Definition and the performance comparison between the thermistor and the RTD

Thermistor and RTD both tons emperatures measuring device. RTD and thermal resistance between the main difference is that RTD made of metal and semiconductor materials used for thermal resistor. Other differences between thermistor and RTD is illustrated in the figure below.

because of the thermal resistor made of semiconductor materials, so they have the negative temperature coefficient and positive temperature coefficient. But most thermistor has negative temperature coefficient, namely the resistance decrease with the increase of temperature. Because the thermistor can detect tiny changes of temperature, so the negative temperature coefficient can be big enough to a couple of percentage points of temperature increase.

RTD by platinum, nickel and other pure metal, has a positive temperature coefficient. Positive temperature coefficient means that their resistance increases with temperature, this is the main function of RTD. RTD is used to measure temperature change.

the definition of RTD RTD resistance temperature detector. RTD is defined as used to measure the temperature of the resistor. It is the working principle of resistance changes with the change in temperature.

the resistance of the conductor with the temperature change, the characteristics of conductor used for RTD temperature measurement. RTD by platinum, nickel, copper and other pure metal. Associated with the conductor resistance change by the following formula.

platinum resistance thermometer equation for RTD, because it can withstand high temperature and high stability. These metals have high temperature coefficient, which is that they increase with the rising of temperature with the temperature, and the nature of the metal is used in RTD.

the definition of a thermistor thermistor is used to measure the temperature of thermistor. It made of semiconductor materials, because it has the positive and negative temperature coefficient. Positive temperature coefficient of mean temperature increased with the increase of resistance increase, and the temperature in the negative temperature coefficient is inversely proportional to the resistance.

thermistor is used to measure the temperature of a small scale, near - 60º C to 15 & ordm; C。 Thermistor resistance in the range of 0. 5 - 0. 75Ω 。 It is used for measuring appliance temperature extremely sensitive equipment.

the main difference between RTD and thermistor:

RTD is an instrument for measuring temperature, the thermal resistance is the thermistor resistance changes with temperature.

RTD by metal, has a positive temperature coefficient thermistor made of semiconductor materials.

compared with thermal resistance, low accuracy of RTD. Thermistor has negative temperature coefficient, so even if the temperature change is minimal, can also be detected.

thermistor small changes to make a quick response, and RTD response time is slow.

thermistor is used to measure 130 & ordm; C temperature range, and RTD temperature as high as 660 & ordm; C。

RTD characteristic curve between resistance and temperature is linear, and the thermistor is non-linear.

compared with thermistor, RTD sensitive enough.

compared with thermal resistor, the size of the RTD is much larger.

thermistor is far higher than the cost of RTD.

compared with thermal resistor, the resistivity of RTD are smaller.

compared with RTD, thermistor lag effect is much higher.

RTD is used to measure the industry of high temperature, while the thermistor used for home appliances small temperature measurement. Conclusion

RTD and thermistors are temperature sensor. RTD is used to measure temperature, thermistor is used to measure the temperature of the small devices.