What are the characteristics of thermistor?
Thermistors are temperature-dependent resistances, normally constructed from metal oxides. The resistance change with temperature is high compared with the metallic resistances, and is usually negative; the resistance decreases with temperature increase. The temperature characteristics are highly nonlinear.
What is a electrical thermistor?
Thermistors are thermally sensitive resistors whose prime function is to exhibit a large, predictable and precise change in electrical resistance when subjected to a corresponding change in body temperature.
What is IV characteristics of thermistor?
For the thermistor, its resistance reduces with the temperature. In case of Thermistor, at higher voltage range when current flow becomes higher the temperature of the conductor also rises, but in this case this reduces the resistance of the thermistor. Lower resistance means higher gradient of the I-V curve.
What is the principle of thermistor?
The thermistor works on the simple principle of change in resistance due to a change in temperature. When the ambient temperature changes the thermistor starts self-heating its elements. its resistance value is changed with respect to this change in temperature. This change depends on the type of thermistor used.
What is the application of thermistors?
Common Thermistor Applications Thermistors are used as temperature sensors. They can be found in every day appliances such as fire alarms, ovens and refrigerators. They are also used in digital thermometers and in many automotive applications to measure temperature.
What are the advantages and disadvantages of thermistor?
The main advantages of the thermistor are large temperature coefficient of resistance, high sensitivity, small heat capacity, fast response; but the main disadvantages are poor interchangeability and non-linearity of thermoelectric characteristics, which is to expand the measurement.
What are the disadvantages of thermistor?
Disadvantages of thermistor
- It needs shielding in power lines.
- It is extremely non-linear.
- It is a passive device.
- The nonlinear characteristics of thermistors often create a problem for temperature measurement.
- It has a narrow operating temperature range compared to RTD and thermocouple.
- It is fragile.
What are the limitations of thermistors?
Disadvantages of thermistor: The thermistor is not suitable for a large temperature range. The resistance temperature characteristics are nonlinear. Narrow working temperature range compared to other sensors such as RTD and thermocouple. More fragile as they are semiconductor devices.
What is the function of a a thermistor?
A thermistor is a temperature sensor whose electrical resistance changes in response to a change in body temperature.
Are thermistors sensitive to temperature?
Although thermistors are very sensitive but on the other hand, it exhibits highly non-linear characteristics of resistance versus temperature. Thermistors are compact and rugged in construction.
What is temperature compensation in thermistor?
Temperature compensation (i.e. maintain resistance to compensate for effects caused by changes in temperature in another part of the circuit) The working principle of a thermistor is that its resistance is dependent on its temperature. We can measure the resistance of a thermistor using an ohmmeter.
How many types of thermistors are there?
There are two types of thermistors: 1 Negative Temperature Coefficient (NTC) Thermistor 2 Positive Temperature Coefficient (PTC) Thermistor More