Introduction to humidimeters

Humidimeters are instruments designed to measure moisture content in various materials and environments. Its main function is to quantify the percentage of water present in an element, which is essential to guarantee quality and durability in sectors such as construction, agriculture, industry and environmental control.

This type of device is used to avoid problems derived from excessive or insufficient humidity, such as structural deterioration, the proliferation of microorganisms or the alteration of physical and chemical properties of materials. Humidimeters can be portable or fixed installation, adapting to different needs and environments.

Humidity measurement methods

Humidimeters can rely on different physical principles to detect and quantify humidity. One of the most common methods is measurement using electrical sensors, which detect changes in the conductivity or capacitance of the material due to the presence of water.

Another common method is the thermo-gravimetric method, which consists of determining the weight loss of a sample when it is heated, although this method is more typical of the laboratory. In the case of portable humidimeters, electrical resistance or capacitance sensors predominate due to their speed and ease of use.

In addition, there are humidimeters that incorporate microwave or infrared technology, capable of evaluating humidity without direct contact with the sample, which is useful in sensitive or difficult-to-access materials.

Electrical sensors in humidimeters

The electrical sensors used in humidimeters work by measuring the conductivity or capacitance of the material. Electrical resistance decreases as humidity increases, since water is a good conductor. For its part, the capacitance varies depending on the dielectric constant of the water versus that of the dry material.

These sensors are designed to be inserted into the material or make surface contact, depending on the model. Measurement accuracy can be affected by factors such as temperature, chemical composition of the material, and measurement depth.