Moisture measurement has always been an important process parameter. For a long time, the standard way to test for moisture was to send samples to a lab for analysis. The most common methods were drying and weighing, but there were also ovens, distillation, spectroscopy, electrochemistry, and other methods.

But these methods are hard to use and take a long time, so they can’t be used for testing on-site. The important thing is that the data you get by spending a lot of time is only old data and not data from the present. It can’t really show how much water is in the materials during the process, so there will always be mistakes.

It is a new way to measure moisture using a microwave. Because the microwave goes all the way through the process material, it is possible to measure all physical moisture. This is true for both the moisture on the outside and the moisture inside. The microwave moisture tester can test the amount of moisture quickly and accurately without any drying or reagents.

At the same time, it can be tested right there to make sure that the measurements are correct. The color and texture of a material’s surface won’t change how it is measured. A Microwave moisture meter is a type of measuring tool that uses the frequency of microwaves to figure out how wet something is. The Microwave moisture meter can be used for lots of different things. It is mostly used to measure the amount of water in soil, cement, walls, and other building materials, as well as in paper, wood, feed, grain, coal, and other things.


The main components of a microwave moisture measuring device are a microwave oscillator and a microwave attenuator. A microwave works because it is a type of electromagnetic wave with a high frequency. The dielectric constant and the tangent value of the dielectric loss angle are the main things that determine the attenuation and phase change caused by a microwave transmitting medium. Water is a molecule that is polar. Water has a much higher dielectric constant and dielectric loss tangent than most other media.

Most of the time, the amount of water in a medium determines its dielectric constant and loss tangent. The microwave comes out of the microwave emission source on the lower arm of the C-frame of the UM Microwave moisture meter, which is below the conveyor belt. After going through the belt and materials, the microwave comes out of the microwave receiver on the upper arm of the C-frame at the top of the belt. Based on how much the microwave power drops and how the phase shift changes, you can figure out how much water is in the material.


The Microwave moisture meter is divided into contact Microwave moisture meters and non-contact Microwave moisture meters. The Microwave moisture meter has different communication and control modes, supports different industrial communication protocols, communication ports, and networking modes, can do simple automatic control and system integration, and can be matched with or connected to other smart devices. No matter how powerful its function is, though, and no matter what kind of Microwave moisture meter it is, it usually has to pass the system calibration data before it can be used to measure materials in an industrial production line in a continuous way.

The non-contact online Microwave moisture meter also comes in two types. One is the penetration type, in which the transmitting probe is below the belt and the receiving probe is directly above the material. The distance between the material and the receiving probe is about 400 mm. The design of the reflection method is simple, and it doesn’t cost much, but the test error is pretty large. For this type of penetration, you need at least one probe that sends and one probe that receives.

For the penetration type, you also need a height (mass) compensation probe along with the two test probes. Since the energy that is sent out goes through the whole belt, it is picked up by the probe on the other side to figure out how much energy was lost. You can figure out how much water is in the belt this way.

The penetration measurement method is used by the on-line Microwave moisture meter. This method can test the average value of material moisture in the whole penetration layer. It adds up the moisture on the surface and inside the material, so the test results are more accurate. There is a probe that sends out microwave energy below. After the microwave goes through the material, there is a probe above to pick up the energy it lost.

The amount of energy lost is used to figure out how much water there is. The microwave principle moisture meter doesn’t care if the material changes color or if its composition changes. When the material’s internal and external moisture levels aren’t the same and its particles are large, it’s best to use the microwave principle because microwaves are a penetrating measurement that gives better test results. But the microwave can’t test materials that are very thin or very thick.

But the microwave can’t test materials that are very thin or very thick. For example, the materials in the pipeline and on the belt are very thin, which changes the way microwaves work and means they can’t be used for testing. In the same way, microwave energy can’t get through thick materials and isn’t good for them.

The microwave can’t test crystal water because of how it works. But microwaves can be used to test a lot of things that can’t be checked with infrared, like coal. A microwave is a good choice.

Also, power plants use different kinds of coal, so the infrared method doesn’t work, but the microwave method does. If the steel plant’s sintering material formula is known, it is best to use infrared. If the formula changes often, it is better to use the microwave. The steel plant should figure out how sensitive the microwave needs to be.

How do you figure out how much moisture something has?

There are two main types of methods for analyzing water: physical analysis and chemical analysis. Different methods for figuring out how much water is in something have slowly replaced the old ones. There are five different types of instruments that measure moisture on the market right now. Most of the time, people look at water in two ways: physically and chemically.

The Karl Fischer moisture meter measures the Karl Fischer method, also called the Fischer method, which Karl Fischer came up with in 1935 as a way to measure the amount of water in something. The Fischer method is a more accurate and specific way to figure out how much water is in different chemical reactions. Even though it is an old method, it has been updated in recent years to make it more accurate and give it a wider range of measurements. It has been listed as the standard way to figure out how much water is in many things.

The Fischer method is a part of the iodometric method. The basic idea behind it is that when iodine is used to oxidize sulfur dioxide, a certain amount of water is needed: 12 S02 2H2O = 2hi H2SO4. The above reaction can be turned around. Alkaline materials must be added to move the reaction in a positive direction and make it happen by a certain amount. Experiments show that pyridine is a better reagent, and pyridine can also be used to lower the vapor pressure of iodine and sulfur dioxide. To make stable pyridine methyl bisulfate from pyridine thioanhydride, mix the reagent with methanol or another solvent with an active OH group.

When far infrared radiation hits an object, it can be absorbed, reflected, or passed through. This is how an infrared moisture meter works. Not all molecules, though, can take in far infrared rays. Only molecules that have two poles and show electricity can work. Far-infrared rays are strongly absorbed by water, organic matter, and polymer matter.

When these substances take in the energy of far-infrared radiation and make the natural vibration and rotation frequencies of molecules and atoms match the frequency of far-infrared radiation, it is easy to make molecules and atoms resonate or rotate, which makes movement much stronger. The heat energy that is turned into work raises the temperature inside the object so that it can be softened or dried quickly.

The dew point moisture meter is easy to use; the device is not hard to understand; and most of the time, the results are correct. It is used to find out how many tiny amounts of moisture are in common gases. But this method causes more interference, and at high concentrations, some gases that are easy to cool will condense before water vapor.

A Microwave moisture meter uses a microwave field to speed up the drying process and dry samples quickly. It has a short measurement time, is easy to use, is accurate, and can be used in a wide range of situations. It can measure the amount of moisture in solid samples that are granular, powdery, or thick, like grain, paper, wood, textiles, and chemical products. It can also be used to find out how much water is in liquid samples like petroleum, kerosene, and other things.

A Coulomb moisture meter is usually used to find out how much water is in a gas. The method is easy and quick, and it works best for finding small amounts of water in gas. If you use general chemical methods to figure it out, it is very hard. It can’t be used to find out by electrolysis whether a substance is an alkene or a conjugated substance.

The difference between an infrared moisture tester and a microwave moisture tester

The moisture meter can detect the moisture content in various organic and inorganic solids, liquids, gases, and other samples. In this chapter, we will introduce the difference between an infrared moisture tester and a microwave moisture tester.

Principle difference

Moisture meter with infrared technology

An infrared moisture analyzer is a piece of equipment that uses infrared spectroscopy to figure out how wet something is. A type of electromagnetic wave is an infrared light wave. All types of electromagnetic waves have a certain amount of energy, and the energy of different wavelengths varies. Electromagnetic waves can be picked up by all kinds of things, but some things pick them up better than others. The electromagnetic waves that come from different molecules also have different lengths, or wavelengths. One molecule can only get the energy of electromagnetic waves with one or a few wavelengths. It can’t get the energy of electromagnetic waves with other wavelengths.

The source of infrared light goes through a twisted filter with two filters that have different wavelengths. One filter passes through infrared-sensitive water, which is the receiving band of water. Another filter can’t be received by water when it passes through multiple wavelengths of infrared light. The infrared light beam shines on the thing to be measured. After being reflected, the light is picked up by the infrared detector and turned into a weak current signal. After expanding, the indicating instrument shows the ratio of the two wavelengths’ signals, which can be used to measure the amount of water.

Microwave moisture meter

The Microwave moisture meter has a microwave resonance frequency of between 2000 and 3000 MHz. When the microwave goes through a material with water in it during transmission, the water molecules absorb some of the electromagnetic energy, which makes the microwave less powerful. On the other hand, the electric field changes the frequency at which positive and negative oxygen ions and hydrogen ions change places in water molecules.

A microwave vibrator and a microwave attenuator make up most of the Microwave moisture meter. A waveguide sends out microwaves. The microwaves go through a sample, which is held down by a microwave attenuator. The results are then shown on a screen.

Comparison of Applications

Since the infrared moisture meter is a non-contact measurement that can be done on-line, it works well with materials that have a high temperature, high humidity, or a high erosion rate. Other measurement limits are large, and there are no special rules about how hot or cold materials have to be. A Microwave moisture meter is a contact measurement, so it has high requirements for the materials being measured, such as temperature, humidity, corrosivity, etc.

The way the product looks doesn’t have much of an effect on the measurement results. After comparing, the best way to choose a moisture measuring tool is to think about the use situation and the object being measured, among other things, in order to get the best results.