The temperature in simple terms can be defined as the degree of hotness of any object. However, it differs for everyone as might feel it hot and the other will feel cold. So for standard measurement, the device used for measurement is called as the thermometer.
Thermometer consists of a sensor which response to temperature change. It has a system which converts sensor response to the values of temperature.
There are basically two types of thermometer:
- Contact thermometer is mainly used for liquid and electricity measurement.
- Noncontact thermometer they are used for radiation measurement.
- It is a device which is used to measure the temperature of a running machine part.
- It functions on thermocouples.
- Thermocouples are the equipment which consists of two different conductors and thus detects the temperature by producing voltage.
Temperature sensor mainly consists of two different types of metals tied at one end, when the junction of these two metals is heated or cooled it produces voltage.
Characteristics of the temperature sensor
While choosing a temperature sensor one should consider the following characteristics:
- While choosing a temperature sensor you must know what are the requirements of your projects.
- Check the temperature range first, as it defines how accurate and quick it measures the temperature.
- Linearity must be checked as linearity is a characteristic that converts the unit of voltage as the unit of temperature changes. In reality, no temperature sensor is completely linear.
- Check its response time, it is the time in which it measures temperature change.
- Durability must be checked before purchasing a temperature sensor. As all type of sensor does not function in all the environmental conditions.
- The durability of the sensor also depends upon the metal used in it.
- The most important is to check the cost of the sensor, as per your project you must have decided how much you can spend on it.
Duct mounted temperature sensor
Duct mounted temperature sensor is an economical solution for temperature measuring requirements. They require certain signalling conditions like; cold-junction compensation, amplification for high resolution, filtering, and linearization.
- It is applied in the thermostat of temperature sensors.
- It is found in the flame sensor of safety devices of the gas run devices.
- They are also used in diesel engines, gas turbine exhaust.
How to choose a thermocouple?
- Before choosing thermocouple to check its temperature range.
- Always see if it is chemical resistant or not.
- Check its installation cost.
Advantages of thermocouple
- They are simple to use and install
- They are inexpensive and do not require any external power source
- They are available in a variety of styles
- They are used for a wide temperature range
Disadvantages of thermocouple
- It gives a nonlinear response
- Another disadvantage is that they are the least stable
- Function on small sensitivity
- They give a small output voltage
There are several websites which provide online services for duct mounted temperature sensor. You should compare the product quality on several websites before purchasing it.