Humidity transmitters and sensors

Humidity transmitter: types, applications and choosing the right device

In an industrial world where precision and accuracy are crucial, humidity transmitters play an invaluable role. These advanced measuring devices are essential for monitoring and regulating humidity in a wide variety of applications, from the food and pharmaceutical industries to energy and building automation. In this article, we take a look at the different types of humidity transmitters, their industrial applications, and share tips on how to choose the right device. Read on!

Humidity Transducers – Types

Humidity transducers, also known as humidity sensors, are devices used to measure and monitor humidity in the air. There are several types of humidity transducers which differ in the technology they operate on, as well as their accuracy and measurement range. Here are some of them:

  • Capacitive Humidity Transducers: These sensors use a dielectric that changes its capacitive properties depending on the humidity of the air. They are very accurate and stable but might be more expensive than other types of sensors. An example of such a device is the humidity and temperature transducer in HVAC systems and building automation from JUMO (product number 907020).
  • Resistive Humidity Transducers: These sensors use a material that changes its resistance depending on the air humidity. They are less accurate than capacitive sensors but are usually cheaper.
  • Thermal Humidity Transducers: These sensors use changes in the evaporation rate of water to measure humidity. They are very precise but can be expensive and require regular calibration.
  • Infrared Humidity Transducers: These sensors use changes in the absorption of infrared light by water vapor to measure humidity. They are very accurate but can be costly and need regular calibration.
  • Psychrometric Humidity Transducers: These sensors use the temperature difference between two thermometers, one wet and one dry, to measure humidity. They are less accurate than other sensor types but are generally cheaper.
  • Dew Point-Based Humidity Transducers: These sensors measure the temperature at which water vapor starts to condense (dew point temperature), which allows determining the humidity of the air. They are very accurate but can be pricey and require regular calibration.
  • Hygroscopic Transducers: A type of sensor that measures humidity based on the absorption of water by a hygroscopic substance e.g., the humidity and temperature transducer and CO2 measurement probe from JUMO (product number 907021).

The humidity and temperature transmitter for HVAC and building automation systems (907020) is an example of a capacitive transmitter

Industrial Applications of Humidity Transducers

Humidity transducers are essential in many different industrial sectors. In the food and pharmaceutical industries, they are used to monitor and regulate humidity during production processes, which is crucial for the quality of the final product. In the energy sector, humidity transducers are utilized to monitor the humidity in generators and turbines, helping to prevent corrosion and damage. In building automation, humidity and temperature transducers are employed to maintain appropriate conditions inside buildings, which is vital for the comfort and health of the occupants.

Measuring temperature and humidity is a key element in managing conditions in warehouses, among others

How to Choose the Right Humidity Measurement Device?

Choosing the right humidity transducer depends on several factors. First and foremost, you need to understand your measurement requirements. Do you need to measure just humidity or also temperature and CO2? What are your requirements regarding the measurement range? Do you need a device for continuous operation in high humidity, or for low humidity applications?

Another factor is the environment in which the device will be used. Is it an industrial environment with a lot of dust and dirt, or is it a clean laboratory setting? Will the device be exposed to extreme temperatures or humidity levels? Or do you need a device for non-aggressive environments?

Last but not least, price is a factor. Humidity transducers can vary in price depending on their features and specifications. It's important to find a device that meets your needs but also fits within your budget.

Key questions to ask include:

  • What humidity range do you need to measure?
  • Are there any chemicals or contaminants present?
  • What accuracy does the application require (1%, 2%, 3%, or 5%)?
  • What drift rate can I accept (1% or 5% per year)?
  • What is the temperature range?
  • Is the device temperature-compensated?
  • Can the transducer be calibrated on-site?
  • What is my budget?

By answering these questions for each application requiring a humidity sensor, you can ensure proper functionality and minimize the costs of purchasing and maintaining the transducer.

The temperature and humidity transmitter (Type: 907027) is ideal for applications that require the monitoring of values such as relative humidity and absolute humidity, e.g. in buildings or industrial proc

Sensors for Measuring Humidity – Summary

Humidity transducers are a key component in many industrial processes, allowing for precise monitoring and regulation of humidity. Choosing the right device depends on several factors, including measurement requirements, working environment, and budget. JUMO offers a wide selection of transducers for measuring both relative and absolute humidity, which are not only accurate and reliable but also tailored for various industrial applications. In our extensive range, we have devices such as humidity transducers with LCD displays and devices for measuring both temperature and humidity simultaneously. Check it out!