How to find wood moisture formula. We determine the moisture content of wood

  1. Measurement Options
  2. Mass measurement
  3. Calculations based on the received data
  4. Measuring instruments

While doing construction works, for the production of furniture and decorative items dry wood is taken, since the wet material “leads” after processing, which spoils the decor of caskets, picture frames, and photographs. Other structures are at risk - doors, door frames, floors, stairs.

Due to the large volumes, it is difficult to determine the level of moisture in the wood, the experience of a specialist is important - all measurements are carried out manually, and the worker may miss (accidentally or intentionally) part of the blanks. And at large woodworking enterprises, selective measurements are made, according to which they find out how many percent of moisture a batch has (5–20 pieces, an average indicator is calculated from the data obtained). The moisture content of wood is determined at enterprises in stages.

It is likely that the part may not be dry enough, and this will cause difficulties for specialists working with the material - craftsmen, furniture makers. Only dry wood is needed, so you have to independently determine its condition.

Execution Methods

There are only 2 ways to find out the water level in wood:

    You can do this using tools. For accurate measurements, a special device is used - a moisture meter. It is designed to determine the level of moisture content in different conditions and for all materials.

    You can measure the moisture content of wood by its mass, it is possible to carry out calculations at home.

There is a GOST that allows the level of moisture content in wood for certain purposes after processing. (GOST 17231-75 and GOST 16483.7-71). Documents are valid on the territory of the CIS countries. They regulate how to select probes, guidelines humidity measurement, analysis and interpretation of the information received.

The process of preparation and work is simple: samples are taken from the batch, which are placed in an oven with given conditions. These are temperature, air humidity, and other factors. After full cycle work of the cabinet, the sample is taken out and weighed, comparing the moisture content of the wood before and after being placed there. GOST provides for tolerances (error of permissible deviation from the given values).

If the workpiece has been lying in the warehouse for a long time (even after drying), then equilibrium moisture content is accumulated. This indicator for the tree is the value that the environment has. For example, during long-term storage in a warehouse, a tree will gain or release moisture so much that, as a result, the moisture content of logs or boards will be equal to this indicator in the room. Therefore, there is a separate GOST, which regulates the moisture rate. The storage conditions of the material must be respected.

Mass measurement

This option is the most accurate, so this is how humidity is determined according to GOST. The method can be changed at home. It does not require special equipment. However, knowledge of physics and some reference data according to GOST are required. It is recommended that you familiarize yourself with GOST before taking measurements in order to have an idea of ​​\u200b\u200bhumidity, what it affects, what value the standard number has, and also to obtain reference data.

The method is based on the fact that any material has a density. Different types of wood differ in this indicator. At the same time, the natural density of wood is much lower than the real one - the tree absorbs moisture. Dry wood is lighter than wet wood. Having obtained the volume and mass of the workpiece, you can check or calculate the moisture content. This option is more reliable than simply using a moisture meter.

It is important to correctly take the initial density data for calculations, since even the same tree species that grows in different climatic conditions has different values. This gives an error.

To make calculations, you need to take a blank 2x2x3 cm, which is cut off from the edges of the board at a distance of about 0.3–0.5 meters.

It doesn't matter which edge of the board the material is cut off from. The next step is weighing. It must be produced on very accurate scales in order to obtain a mass indicator of up to 0.1 grams. After that, the volume and density of the material are calculated.

Calculations based on the received data

For comparison with the obtained calculated data, the natural density of wood is taken. The difference between the calculated and natural value will be an indication that the tree is wet. To determine the exact value, the workpiece is placed in an oven at a temperature of 100 ° C (an oven can be used in everyday life) for a quarter of a day. After that, the workpiece is removed, re-measured and weighed.

Calculations are performed as follows:

W = (m-m0)/m0 x100%, where: m is the mass of the workpiece before the drying cabinet, m0 is the mass after removal from the dryer, W is the moisture content.

The disadvantages of this method are long time receiving and processing information, the need to choose exact values ​​from reference materials(natural density). However, the result will be accurate.

Measuring instruments

To determine the moisture content of wood, you can use a device that allows you to find out approximately what percentage of water is contained in the material. The only requirement for such work is the presence of a moisture meter, which is quite expensive. Most enterprises have such a device at their disposal and, if agreed, all measurements can be taken.

The principle of operation is based on the phenomenon of electrical conductivity in various media. The device has two needle sensors, which should be stuck into the workpiece to the same depth, after which current passes through them. At the same time, the norm of dry wood is already incorporated into modern devices, which allows you to check the data with the established values ​​​​for a particular species. The whole operation takes about a minute.

The disadvantages of this method include a high error. For the best devices, it is 1.5–2%, for most it can reach up to 3–4%. In addition, it is difficult to stick the needles to the same depth, which gives significant deviations.

When buying lumber for the construction or manufacture of furniture, windows or other products, many people want to get high-quality and reliable material. But often purchased wood is not dried out, which results in cracking, deformation or damage due to the development of the rotting process.

The question of how to check the moisture content of wood is relevant and remains so. Moisture meters are mainly used to measure humidity. Both industrial and household purpose. Below is a table showing the density different varieties wood. And then, consider the method of how to determine the moisture content of wood without a moisture meter in 2 ways.

How to determine the moisture content of wood without a moisture meter?

For those who do not know how to determine the moisture content of wood, you can use special tables. According to them, knowing the type of wood, you can determine its density. These tables summarize the indicators obtained as a result of laboratory studies using special diagnostic research equipment.

Knowing that each type of wood is unique in structure, mass and density, and using tabular data, it is possible to determine the moisture content of a particular sample in field conditions. What is important for the implementation of further heat treatment.

Below we will consider how to determine the moisture content of wood, based on tabular values ​​​​and using simple measurements:

  • The first step is to measure the mass and volume of the sample. These manipulations are performed in the usual ways using the simplest devices.
  • The formulas calculate the density of the material. At the same time, it is necessary to remember the error, which in any case will arise due to the difference in the places where the trees grow. In some it is larger, in others it is lower.

In addition, the humidity can be different in different parts tree. For example, in the trunk it is about 50% for pine and 60% for spruce. The branches, being less massive, and due to regular blowing, contain no more than 56 for pine, and 46 for spruce.

The tops of the trees contain up to 60% moisture, and the bark accumulates from 36 to 67. Considering all these indicators, it is necessary to determine the average for all parts of the tree in order to further use the obtained value in the calculations of intermediate values.

Undoubtedly the most important indicator when building from lumber, the moisture content of wood is, the methods for determining it are to carry out certain measurements. The first step is to determine the absolute humidity. As practice shows, this is more of a theoretical indicator that reflects the amount of water in the remaining volume of wood. It is determined by the following formula:

The next step is to determine the moisture content of the wood at the time of inspection, taking into account the calculated relative humidity. Calculations are carried out according to the following formula:

In addition to the above types of moisture, there are also 2 types of moisture found in the thickness of the wood. These include free moisture and bound moisture. In the first case, water is located in the cell cavities and intercellular space. Bound moisture is located inside the cell walls, which makes it difficult to remove from them, and remaining inside.

A dry board is different from a wet board:

  • weight,
  • color,
  • smell,
  • ringing - if you hit it

How to measure the moisture content of wood scientifically?

There is also a second way to find out the humidity. It consists in the study of a prototype with dimensions of 20x20x30 mm. In this case, the sample is taken not from the very edge, but further from it at a distance of 30-50 cm. As a rule, in this zone it is maximum and was not subject to natural evaporation.

To measure the moisture content of wood, a weight method is used, the cut sample is weighed on a balance with high accuracy. At the next stage, the sample is placed in an oven, in which the temperature is maintained at 101-104 degrees. The heat treatment procedure continues for 6 hours. After the sample is removed and weighed again and returned back to the cabinet.

The results obtained in this way are entered into a summary table. If the second measurement yielded a similar result to the first one, then the wood is considered absolutely dry.

See also:

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Contents Wood MoistureInitial wood moisture formula: To obtain quality lumber that will be minimally subject to linear changes under the influence of moisture environment, it is necessary to organize the correct drying of the material. But this sometimes requires preliminary calculations of the moisture content in the wood structure at the actual moment. Moisture content of wood First of all, it is necessary to deal with the concept […]

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The tree is natural material, highly susceptible to fluctuations in temperature and humidity. The main property of wood is hygroscopicity, that is, the ability to change humidity in accordance with environmental conditions. It is said that wood "breathes", that is, it absorbs air vapor (sorption) or emits them (desorption), reacting to changes in the microclimate of the room.

Measuring the moisture content of wood with a moisture meter

Absorption or release of vapors is carried out due to the cell walls. With a constant state of the environment, the moisture content of wood will tend to a constant value, which is called the equilibrium (or stable) humidity.

The ability to absorb moisture is affected not only by the microclimate of the room, but also by the type of wood. The most hygroscopic species are beech, pear, kempas. They respond most quickly to changes in humidity levels. In contrast, there are stable species, such as oak, merbau, etc. These include the bamboo stalk, which is very resistant to adverse climatic conditions. It can be laid even in the bathroom.
Different types of wood have different levels humidity. For example, birch, hornbeam, maple, ash have low humidity(up to 15%) and, when dried, tend to crack. Humidity of oak and walnut is moderate (up to 20%). They are relatively resistant to cracking and do not dry out as quickly. Alder is one of the most desiccation-resistant species. Its humidity is 30%.

Humidity- one of the main characteristics of wood. Under the moisture content of wood is understood the ratio of the mass of water to the dry mass of wood, expressed as a percentage.

absolute moisture content of wood is the ratio of the mass of moisture in a given volume of wood to the mass of absolutely dry wood. According to GOST, the absolute humidity of parquet should be 9% (+/- 3%).

Relative humidity of wood is the ratio of the mass of moisture contained in wood to the mass of wood in a wet state.

There are two forms of water in wood - bound and free. They are made up of total amount moisture in wood.

Bound (or hygroscopic) moisture is contained in the cell walls of wood, and free moisture occupies half of the cells and intercellular spaces.

Free water is removed more easily than bound water and affects the properties of wood to a lesser extent.
According to the degree of moisture, wood is distinguished into the following types:

wet wood
Its humidity is over 100%. This is possible only if the wood has been in the water for a long time.

Freshly cut
Its humidity ranges from 50 to 100%.

Air dry
Such wood is usually stored in the air for a long time. Its humidity can be 15-20%, depending on climatic conditions and seasons.

Room dry wood
Its humidity is usually 8-10%.

Absolutely dry
Its humidity is 0%.

With prolonged drying, water evaporates from the wood, which can lead to significant deformations of the material. The process of moisture loss continues until the level of moisture in the wood reaches a certain limit, which directly depends on the temperature and humidity of the surrounding air. A similar process occurs during sorption, that is, the absorption of moisture. The decrease in the linear volumes of wood when bound moisture is removed from it is called shrinkage. Removal of free moisture does not cause shrinkage.

Shrinkage is not the same different directions. On average, complete linear shrinkage in the tangential direction is 6-10%, and in the radial direction - 3.5%. With complete shrinkage (that is, one in which all bound moisture is removed), the moisture content of the wood decreases to the limit of hygroscopicity, that is, to 0%. With an uneven distribution of moisture during the drying of wood, internal stresses can form in it, that is, stresses that occur without the participation of external forces. Internal stresses can cause changes in the size and shape of parts during the mechanical processing of wood.

The properties of wood directly determine the properties of wooden products. With excess or insufficient moisture, wood usually absorbs or releases moisture, respectively increasing or decreasing in volume. At high humidity indoors, wood can swell, and with a lack of moisture, it usually dries out, so everything wooden crafts, including floor coverings, require careful maintenance.

To prevent deformation of the flooring in the room, it is necessary to maintain a constant temperature and humidity. This has a positive effect not only on quality and durability. floor coverings And wooden furniture but also on people's health. With a sharp change in the temperature and humidity conditions in the room, internal stresses arise in the wood, which lead to cracks and deformations.

The optimum temperature in a room with parquet flooring should be approximately 200C, and the optimum air humidity should be 40-60%. Hydrometers are used to control the room temperature, and relative humidity maintained indoors with humidifiers.

WOOD MOISTURE DETERMINATION

There are several ways to determine the moisture content of wood. IN living conditions use a special device-electric moisture meter. The operation of the device is based on the change in the electrical conductivity of wood depending on its moisture content. The needles of the electric moisture meter with electrical wires connected to them are inserted into the tree and an electric current is passed through them, while the moisture content of the wood is immediately noted on the scale of the device in the place where the needles are inserted.

Many experienced carvers determine the moisture content of wood by eye. Knowing the types of wood, its density and other physical properties, it is possible to determine the moisture content of wood by weight, by the presence of cracks at the end or along the fibers of the wood, by warping and other signs.

By the color of the bark, its size and the color of the wood, one can recognize ripe or freshly cut wood and its degree of moisture. When processing with a p / m planer, its thin shavings, squeezed by hand, are easily crushed - which means the material is wet. If the chips break and crumble, this indicates that the material is dry enough.

When transverse cutting with sharp chisels, they also pay attention to chips. If they crumble or the wood of the workpiece itself crumbles, this means that the material is too dry. Very wet wood is easily cut, and a wet mark is noticeable at the cutting site from the chisel. But it is unlikely that it will be possible to obtain a high-quality thread as a result, since cracking, warping and other deformations cannot be avoided.

DRYING WOOD

Wood drying is the process of removing moisture from wood to a certain percentage of moisture.
Dry wood has high strength, warps less, does not rot, easily glues, finishes better, and is more durable. Any wood of various species is very sensitive to changes in environmental humidity. This property is one of the disadvantages of timber.

At high humidity, wood easily absorbs water and swells, and in heated rooms it dries out and warps. Wood humidity up to 10% is sufficient indoors, and no more than 18% outdoors. There are many ways to dry wood. The simplest and most affordable is the natural type of drying - atmospheric, air. It is necessary to dry the wood in the shade, under a canopy and in a draft.

When dried in the sun, the outer surface of the wood heats up quickly, while the inner remains damp. Due to the difference in stresses, cracks form, the tree quickly warps. Boards, beams, etc. p / m are stacked on metal, wooden or other supports with a height of at least 50 cm. Boards are stacked with inner layers up to reduce their warping.

It is believed that the drying of boards placed on the edges is faster, as they are better ventilated and moisture evaporates more intensively, but they also warp more, especially material with high humidity. A stack of p / m, harvested from freshly cut and live trees, is recommended to be compacted from above with a heavy load to reduce warpage.

During natural drying, cracks always form at the ends, to prevent their cracking and preserve the p / m, it is recommended to carefully paint the ends of the boards oil paint or impregnate with hot drying oil or bitumen to protect the pores of the wood. It is necessary to process the ends immediately after the transverse cuts into the cut.

If the tree is different high humidity, then the end is dried with a flame blowtorch and then paint over. Trunks (ridges) must be debarked (cleaned of bark), only at the ends they leave small belts-couplings 20-25 cm wide to prevent cracking. The bark is cleaned so that the tree dries out faster and is not affected by beetles.

The trunk, left in the bark, in relative heat with high humidity quickly rots, is affected by fungal diseases. After atmospheric drying at warm weather wood moisture content is 12-18%.

Wood drying methods

Evaporation method Or steaming has been used in Russia since ancient times. The workpieces are sawn into pieces, taking into account the size of the future product, they are laid in ordinary cast iron, sawdust from the same workpiece is poured, poured with water and placed for several hours in a heated and cooling Russian oven “languishes” at t = 60-700C. In this case, “leaching” occurs - the evaporation of wood; natural juices come out of the workpiece, the wood is painted, acquiring a warm, thick chocolate color, with a pronounced natural texture pattern. Such a workpiece is easier to process, and after drying it cracks and warps less.

Waxing method The blanks are dipped into melted paraffin and placed in an oven at t=400C for several hours. Then the wood dries out for a few more days and acquires the same properties as after steaming: it does not crack, does not warp, the surface becomes tinted with a distinct texture pattern.

Method of steaming in linseed oil Tableware made of wood steamed in linseed oil is very water-resistant and does not crack even with everyday use. This method is still acceptable today. The workpiece is placed in the container, poured linseed oil and steamed over low heat.

Wood - affordable, environmentally friendly pure material widely used in the construction and decoration of buildings. However, many refuse it for the reason that over time the wood begins to warp, cracks appear in the structures. This happens as the wood dries. You can avoid this problem if you work with dry material. Moisture standards for lumber are regulated by a number of documents, in particular SNiP II-25-80.

In order to obtain a high-quality and reliable structure, it is necessary to use only dry wood in construction.

But how to find out the moisture content of wood when buying? It's hard to tell by eye. Only a specialist with extensive experience can determine by some signs whether the wood is wet or dry, but even he will not give an exact percentage. Some conclusions about moisture can be drawn when processing lumber. If the chips removed by the planer are plastic and bend, then the wood is damp, if it crumbles, it is dry. Building regulations require an exact figure, and there are a number of methods for determining it, the most used of which are calculation by weight and calculation using a special device - a moisture meter.

Calculation of wood moisture by weight

Figure 1. Density table various kinds wood.

It is known that different tree species have different densities. But the density depends not only on the breed, but also on the moisture content of the lumber: the drier the wood, the lighter it is. Data on the most common rocks are presented in the table in Figure 1. Knowing the volume and mass, you can calculate the density, find it in the table for given tree and thus determine the moisture content of the wood. It is quite simple and fast way humidity determination. However, it should be borne in mind that the density of trees, even of the same species, but growing in different climatic zones, may vary, so errors in the calculations cannot be avoided.

For more exact definition lumber moisture content is being studied. For testing, a sample of 20x20x30 mm is taken. The sample is cut off from the lumber at a distance of at least 30-50 cm from the edge of the board. It is weighed on a balance with an accuracy of 0.1 g and placed in a drying cabinet with a temperature of 101-104 ° C. After 6 hours, the sample is taken out of the cabinet, re-weighed and put back into the cabinet. Subsequent weighings are carried out at intervals of 2 hours. The weighing results are recorded in the journal. If the difference in weight between two weighings does not exceed 0.1 g, then the wood is considered absolutely dry.

The absolute moisture content of the material is calculated by the formula:

W=(m-m 0)/m 0 ×100(%),

where W is the humidity, m is the mass of the sample at the first weighing, m 0 is the mass of the same sample after complete drying.

It is necessary to consider how to determine the moisture content of a sample using an example. It can be assumed that before drying it weighed 98.76 g, after drying - 65.81 g. Then W \u003d (98.76-65.81) / 65.81x100 \u003d 50.1%.

To obtain a reliable result, it is necessary to conduct a study with several samples. It is not recommended to keep samples of resinous rocks in an oven for more than 20 hours.

This method for determining the moisture content of wood complies with GOST 16483.7-71, but it takes a lot of time and requires special laboratory equipment.

Determination of humidity with a moisture meter

A moisture meter can be used to determine the moisture content of wood.

Scientific and technological progress, manifested in all areas human activity, did not stand aside in relation to such an issue as determining the moisture content of wood. Today, no one is surprised by a moisture meter. The cost of this portable device depends on the manufacturer, model and feature set, but it is not so high as to refuse it. convenient fixture. Moisture meters are available in almost any warehouse where lumber is stored or sold. Therefore, the measurement of humidity turns into a matter of minutes.

The principle of operation of the moisture meter is based on measuring the resistance when passing through wood electric current. The device has needle sensors that penetrate into the lumber along the grain. When the measurement button is pressed, a current is passed through them, and the result, already converted into a moisture indicator, is instantly displayed on the display. The measurement error of modern moisture meters is no more than 1.5%. It should be understood that the result is reliable only for the place where the needles are deepened. To judge the condition of the lumber as a whole, it is necessary to make as many measurements as possible along the entire length and width of the board.

A number of models have a long conductor connecting the instrument to the needle probes. This allows you to measure the moisture content of wood remotely during its drying in the chamber. In this case, the sensors are inserted into the boards located in the middle of the stack. The device itself is placed outside the chamber. When measuring, it is necessary to make corrections for temperature. The remote method is convenient for controlling the drying process of wood, but it should be recognized that it often gives distorted results. This happens for two reasons: due to the heating of the sensor needles, which transmit it to the wood in places of deepening, and due to a violation of the tight contact of the sensors due to the drying of the wood.

In cases where even minimal damage to wood is highly undesirable, for example, when it comes to furniture parts, you can determine the moisture content of wood with a non-contact moisture meter. It does not have needles, but is simply applied to the surface of the lumber. The principle of operation of the device is based on measuring the length of electromagnetic waves, which will differ depending on humidity. When measuring with such a moisture meter, wood should be determined by species.

Drying wood

Wet wood is not a sentence yet. It is quite possible to bring it to a state suitable for work even without drying in the chamber. Moreover, atmospheric drying is recommended for any purchased lumber.

Comes down to her proper storage. To do this, a place is equipped in a draft, protected by a canopy from precipitation and direct sun rays. The last condition is due to the fact that under the sun the surface of the boards quickly heats up and dries, while the bottom remains wet. Because of this, stress arises, the wood warps and cracks.

Under the stacks, logs are installed with a height of at least 0.5 m from ground level. The surface of the base must have a strictly horizontal orientation. In order to avoid deflection of the boards, the distance between the support points should not exceed 1.5 m. conifers 25-40 mm thick, and after 1.0-1.5 m - gaskets 100-150 mm thick. This will provide better air circulation. It is impossible to store boards with different moisture content in one pile: wood is hygroscopic, and dry lumber will absorb moisture from wet ones.

The time required to dry to 18-22% moisture varies from 9 to 40 days. It depends on climatic conditions, time of year and material thickness.

There are several ways to determine the moisture content of wood. They differ in their approaches, but the result is approximately the same. Before you wonder which detection method is best to use, you should know what kind of wood you have and what is the humidity of the air around you. Each type of wood has its own quality standards.

If you do not take into account the moisture content of the material, then subsequently ready product may deform.

Determining the moisture content of wood is extremely important point, which must be observed before construction begins.

The tree is often floated down the river, at the time of delivery it can absorb a large amount of water. Moisture penetrates the structure of the tree and expands it, over time it will evaporate, for this the wood is dried. Of course, it is possible to make boards from wet wood, but in the future they will crack, dry out and lose their original appearance. That is why every newly arrived batch of wood should be carefully checked.

So, there are two most common ways to determine the moisture content of wood. The first involves the use of accurate scales, and the second requires the presence special device called an electric moisture meter.

Weight method for determining moisture

To carry it out, you need to have:

  • ultra-precise scales (up to mg);
  • boards;
  • saws;
  • rulers.

It is as follows:

  1. A small bar is cut out of the board, which should become a control sample. It is also called the humidity section. It is very important to take a control sample in the middle of the board or after 30-50 cm from the end. You will not need the end segment, the readings of its moisture content are irrelevant, since this part has less moisture than the rest of the lumber.
  2. The width of the moisture section should be 10-15 mm. After sawing, it is thoroughly cleaned of sawdust and burrs and weighed on special technical scales. Such scales are able to show the most accurate figure, up to one hundredth of a gram.
  3. The received data should be recorded. Conventionally, this figure can be denoted as Ph - the initial mass of the sample.
  4. After the bar has passed the weighing procedure, it is sent to a special drying cabinet. The temperature in such a cabinet is maintained at the level of 100-105 ° C.
  5. For several hours, the sample is removed from the cabinet and re-weighed, recording the readings. The first control weighing is carried out 5 hours after the bar is placed in the drying cabinet. All subsequent weighings are done every 1-2 hours.
  6. When the weighing starts to repeat, you will get absolutely dry wood. This indicator should be fixed and designated as Pc - the last mass of the sample.
  7. You can determine the moisture content of wood in percentage terms using the following formula:

W = (Ph-Pc) / (Pc * 100%),

Where W is the initial moisture percentage;

Ph is the initial mass of the sample;

Pc is the last mass of the sample.

Experts advise: to obtain more accurate results, it is advisable to use not one control sample, but two.

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Measuring humidity with an electrical device

Non-contact moisture meter allows you to measure the moisture content of wood up to 4 cm thick.

Using the first method takes a very long time. It will take you about 8-9 hours to measure wood moisture in this way. Yes, and not everyone has a drying cabinet. It is much easier to use a special tool that will allow you to quickly and accurately measure the moisture content of a tree.

The principle of operation of the electric moisture meter is based on the laws of physics and is determined indirectly. And the data obtained are based on the indicators of ohmic resistance, which, in turn, will directly depend on the value of hygroscopic moisture in the wood fibers.

Beyond the limits of hygroscopic humidity, the direct dependence of the value of humidity and electrical resistance is strikingly different. Therefore, in this case it is possible to measure the moisture content of wood by using an electric moisture meter, but the probable error will increase significantly.

Most of the designs that are produced in mass production are battery-powered and can be used to measure wood with a moisture content of 7% to 60%. Similar devices built on a bridge.

A current flow passes through the test block of wood, gradually increases and is measured by a device, a microammeter. Its scale is already calibrated and shows what percentage of moisture the test tree has.

The instrument scale has two main ranges with varying degrees of error. The first range is designed for wood moisture content from 7% to 24%, the error in this case is 1-2%. And the second range measures wood with high humidity from 22% to 60%, here the possible discrepancy in the calculation can reach 10%. The error can be displayed both upwards and downwards.

Through the use batteries with the possibility of recharging from a household power supply, the device is mobile and compact.