Differences between contact and non-contact temperature sensors
Differences between contact and non-contact temperature sensors
Blog Article
Ever wonder how your car engine or the air conditioner knows how hot it is? They use that piece of technology called a temperature sensor. A temperature sensor is a specific sensor that is used to measure the hotness and coldness of a substance. Temperature sensors are broadly classified into contact and non-contact sensors. Let’s explore these two types and their differences, and when to use each one.
Contact Temperature Sensors
Let’s start out with contact temperature sensors. These sensors physically make contact with the object being measured. They resemble long, thin thermometers that one might find in a kitchen or at a doctor’s office.
Contact temperature sensors have one significant advantage; they are extremely precise. Because a probe touches the object directly, it gives us an accurate temperature reading. Such contact temperature sensors are why we commonly find them within cooking thermometers, which notify us that our food is cooked, and medical thermometers, which indicate whether we are feverish or not. We need accurate measurements in both of these cases to keep us safe and healthy!
Using a contact sensor is by far the more reliable means of measuring the temperature. You can also think of this as baking a cake. When you do this, and a cooking thermometer inserted into the cake batter reads some temperature, you want to know precisely how hot it is, so that your cake perfectly comes out!
Infrared (non-contact) Temperature Sensors
So, now let us discuss non-contact temperature sensors. They do not come in contact with the target they are measuring. They throw around something called infrared radiation to figure out the temperature instead. You might have seen non-contact temperature sensors in stores or at hospitals that scan your temperature when you walk into the place!
The nice thing about the non-contact temperature sensors is they are easy to operating. You don’t have to touch anything in order to get a temperature reading. You simply point the sensor toward the object whose temperature you wish to measure and it will give you the temperature. This is very useful in situations where direct contact isn’t advisable, such as when checking the temperature of a hot stove or a running machine.
For instance, if a firefighter needs to check the temperature of a wall that could be too hot to touch, they can safely use a non-contact sensor to do so. So, this helps keep them safe while they do their job!
The basic sensor types that produce electrical conductivity and act as a constant potentiometer are unexpected due to microcontroller testing limits.
Despite the accuracy of contact temperature sensors, there are limitations as well. One key limitation of even the best infrared thermometers is that they can only detect the temperature at the point they touch an object. So, to give an example, if we want to find out the temperature of something that is large, e.g., a large pot of soup, we would have to take the sensor around at several spots and take readings at different positions to get a good idea of the temperature.
Moreover, contact sensors can accumulate dirt or grease. If an object's surface isn't clean, it can cause those temperature measurements to be inaccurate. It’s like trying to take a temperature reading on a grill that’s covered in grease — that grease is going to throw off how accurate that reading is. Also, if the object you are measuring is in motion or shaking, this can also affect that measurement.
Comparing Accuracy of Sensors
When it comes to accuracy, both contact and non-contact sensors have their advantages. Because contact temperature sensors are physically touching the object, they are very accurate and provide us with exact temperature readings. The fact that you can measure the temperature of a large area without actually touching anything is also a plus that non-contact temperature sensors have. This is particularly useful when you need to obtain an overall idea of the temperature in a wide area, such as in a room or across a large piece of machinery.
If done correctly, both types of sensors can be highly accurate. But it depends on context and what you’re trying to measure. A contact sensor would be perfect for trying to check the temperature of a hot cup of tea, for example. But, if you want to measure the temperature of a big machine, a non-contact sensor would do a better job!
Types of contact and non-contact temperature sensors
But well actually, where do we use contact and non-contact temperature sensors? Below are a few examples demonstrating their usages:
Contact Temperature Sensors:
Cooking Thermometers: Used to determine the internal temperature of food as it cooks. They list these people as food safety inspectors, making sure our meals are safe and delicious!
Medical Thermometers: These are devices used to measure your body temperature as you touch your skin. These are used by doctors and nurses to see if someone’s temperature is high, so they know how to treat their patients.
HVAC Systems – HVAC is short for heating, ventilation, and air conditioning. There are systems that cut into your ducting and use contact sensors to register the air temperature going in and out of your house. This enables us to maintain comfortable homes year round.
Thermal Safety & SecurityDecember 15, 2020Non-Contact Temperature Sensors
Infrared Thermometers: These instruments accurately assess temperatures at a distance. They are commonly used in the kitchen or in hospitals to measure people’s temperatures quickly.
Thermal Imaging Cameras: Using non-contact sensors, these cameras create a visual image of the temperature differences across a large area. It can also identify locations that are too hot or too cold.
Manufacturing Machines: Non-contact type sensors can be utilized to monitor the temperature of the machines in a factory. This allows employees to identify problems sooner and resolve them before leading to something more significant.
Both contact and non-contact temperature sensors are very important, as you can see. Everything has its specific purposes and advantages. Now that you know a bit more about the differences between contact and non-contact temperature sensors, you can begin to appreciate just how useful they are in our everyday lives. Temperature sensors are an essential part of our safety and awareness of our surroundings, whether you have to measure the temperature of your food, your body, or machines.