Here’s All You Need to Know About Temperature Sensors

Temperature Sensors

If you weren’t consciously aware before, then you’re about to find out that we all have been using temperature sensors in our daily lives. They could be in the form of microwaves, thermostats, water heaters, refrigerators, and many more domestic appliances.

Temperature sensors typically have many applications, and the geotechnical monitoring field is one of the many applications. As a matter of fact, temperature sensors are a rather simple instrument that has the ability to measure the degree of hotness and coolness, and further convert them into a readable unit.

However, have you ever wondered just how exactly the temperature of huge concrete structures, boreholes, soil, and of buildings are measured? Well, this is simply done through some of the most specialized temperature sensors out there.

Temperature sensors are specially designed to keep a regular track of how effective your appliances are. These sensors come in a form of a device that provides a measurement in a readable form via an electrical signal.

In this article, we will be sharing how temperature sensors work, and their different types. Let’s dig in!

What Are Temperature Sensors Used for?

There is more than just one type of temperature sensor. That said, the most common way to distinguish them is based on their mode of connection which consists of contact and non-contact temperature sensors.

Contact temperature sensors have thermocouples and thermostats as they are in direct contact with certain appliances or objects that they have to measure. On the other hand, non-contact temperature sensors simply measure the thermal radiation being released by the heat source.

Such non-contact temperature sensors are often utilized in hazardous spaces, such as thermal power plants or nuclear power plants. 

What do Temperature Sensors Do?

Once again, temperature sensors measure the amount of hotness and coolness in a certain appliance or object. The entire working of a temperature meter ultimately relies on the voltage across the diode.

The temperature change is always proportional to that of the diode’s resistance. In other words, the cooler the temperature, the lower the resistance, and vice-versa. The resistance is measured and further converted into readable units like Celsius, Centigrade, Fahrenheit, and more.

This temperature measurement is displayed in the form of numerical over-readout units.

How Do Temperature Sensors Work?

The basic principle as to how temperature sensors work is the voltage across the diode terminals. If there is an increase in voltage, there will be an increase in the temperature, followed by a voltage drop.

Moreover, the change in temperature is detected by the in-built Encardio-rite wire sensor that vibrates, and then it is converted into electrical signals, which are then transmitted to the read-out unit.

What are the Different Types of Temperature Sensors?

Temperature sensors come in various shapes, sizes, and types. As mentioned earlier, contact and non-contact temperature sensors are the two main types of temperature sensors available. These two sensors are further divided into various types, such as: 


A thermostat is a contact temperature sensor that includes a bi-metallic strip. This strip is made up of two dissimilar metals like aluminum, nickel, copper, or tungsten. The only difference is its coefficient linear expansion of both the dissimilar metals, which causes them to create a mechanical benign movement whenever it senses heat.

For instance, the Google Nest Temperature Sensor makes sure a particular room is warmed or cooled to the exact temperature you want. These temperature sensors work best with the Nest Thermostat or the 3rd gen Nest Learning Thermostat.


Thermistors are also known as thermally sensitive resistors. These temperature sensors shift their physical appearance when its subjected to a change in temperature. These thermistors are of ceramic material, which gives them the ability to deform without any difficulty.

Most thermistors consist of negative temperature coefficients. This means that their resistance decreased when there’s an increase in temperature. Of course, there are some thermistors that consist of a positive temperature coefficient, but negative ones are more common.

Resistance Temperature Detectors

Resistance Temperature Detectors are also known as resistance thermometers. These temperature sensors measure temperature by the resistance of the detector’s element with the temperature itself.

Platinum is the most common and accurate material for a Resistance Temperature Detector, which’s more on the expensive side.


There are more types of contact and non-contact temperature sensors other than the one mentioned above. Both contact and non-contact temperature sensors are used in hazardous spaces.

We hope now you have a better understanding of how temperature sensors work and the different types of them!

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