Temperature Sensors For Arduino Projects

1. What are temperature sensors?

Usually, temperature sensors are designed based on thermistors or thermocouples. They are used for collecting data from a specified area such as open-air, water, soil, etc.

2. Why we use temperature sensors in Arduino projects?

Temperature sensors are ubiquitous in Arduino Projects because you may always want to know your surrounding data like environment temperature, water temperature or soil temperature, etc. So there are many types of temperature sensors such as waterproof water temperature sensors, air temperature sensors, soil temperature sensors to help you get the data you want.

3. 4 Types of temperature sensors for Arduino

1. Thermistors

Thermistors can change their resistance value from the different temperature environment. Usually, when the temperature goes high, the resistance value goes down, we call this thermistors NTC(negative temperature coefficient) thermistor. On the contrary, with the proportional relationship between temperature and resistance value, the thermistor is called PTC(positive temperature coefficient) thermistor. We can get the exact temperature based on the value of the resistance of the thermistor.

Example

1. Temperature sensor with steelhead

• Waterproof
• MF52 NTC thermistor
• Temperature range: -40 °C~125 °C
• Precision: ±5°C
• Low price

This temperature sensor can work under the water and it may roughly detect the water temperature due to its poor accuracy. But it has a very material benefit price. So it can be used in some small project that doesn’t need high accuracy.

2. Grove – Temperature Sensor

• NTC Thermistor
• Temperature range: -40 °C~125 °C
• Precision: ±1.5°C

This sensor is more accurate in the NTC thermistor family. It can be used to measure the open-air temperature.

2. Thermocouples

This type of temperature sensor is based on the thermocouple technology. When the device is put a voltage, the heat will transmit from one side to the other side of the device which produces a heat difference. The heat difference will enable the electric charge diffuse from the heat side to the cool side to form a current. And the value of the temperature determines the current value which can be measured to confirm the temperature value.

Example

1. Grove – High-Temperature Sensor

• Thermocouples
• Big temperature range: -50~600°C
• Precision: ±2°C

Thermocouple sensor usually has a wide temperature range, it can be used in the industrial environment.

3. Semiconductor Sensors

Semiconductor sensors are in the form of ICs. These are known as IC temperature sensor. They have two types: voltage output temperature sensor and current output temperature sensor. They are widely used in every environment conditions. Moreover, their output is always a digital signal which contains the value, so they are easy to program.

Example

1. Grove – Temperature & Humidity Sensor Pro (AM2302/DHT22)

• (AM2302/DHT22) Semiconductor sensor
• Temperature range: -40 °C~80°C
• Precision: ±0.5°C
• Also can measure humidity

DHT22 temperature sensor is commonly seen Arduino project by its low cost and high accuracy.

2. One Wire Temperature Sensor

• Waterproof
• One wire interface
• DS18B20 Semiconductor sensor
• Temperature range: -55 °C~125°C
• Precision: ±0.5°C

DS18B20 temperature sensor is also widely used in many cases, especially for water temperature measurement due to its high precision and stability.

4. IR sensors

IR sensor is an electronic device which is used to sense certain characteristics of its surroundings by either emitting or detecting IR radiation. These sensors are none connecting sensor. They only get the temperature data based on the heat radiation so you may not get the data you want. It is widely used in infrared sensors which is good at detecting the temperature variation.

Example

1. Grove – Infrared Temperature Sensor Array (AMG8833)

• Temperature detection of two-dimensional area: 8 × 8 (64 pixels)
• I2C output (capability of temperature value output)
• High precision
• Long detection distance

This infrared temperature sensor is an RTS(Real-time system), it can detect the environment temperature variation quickly and fast.

4. Summary

The sensors I introduced above can fit any requirement in your project. If you want to get more sorts of temperature sensors, please view our website. At the end of the blog, a table will be showed to compare all 4 types of temperature to lead you get the best choice in your Arduino project.

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