How to make a weather house hygrometer with your own hands. Moisture meters for wood: review of the best models. How to use a hygrometer: step-by-step instructions Tools and materials

A psychrometer is used to monitor temperature and humidity levels. Of course, after spending a certain amount of time, you can purchase it in a store. Whereas it is not at all difficult to make a psychrometer for an incubator with your own hands - the table for it is in this article.

What is a psychrometer?

This is the name of a special device whose purpose is to measure air parameters. Most often, this device is used to measure air humidity - an indicator very important for the efficient operation of the incubator. The operation of the device is based on the physical property of water to evaporate. As a result, there is a difference in temperature readings on a dry thermometer and one that is immersed in a humid environment. Relative humidity is determined from the table - its value is at the intersection of the readings of a pair of thermometers, or as they are also called - thermometers.

We make a psychrometer ourselves

Making this meter yourself is not at all difficult.

Drawing of a homemade device

Tools and materials

To manufacture the device used for the incubator, you will need the following components:

• two alcohol thermometers used to measure ambient temperature;
• some wooden slats different sizes;
• small screws;
• a piece of cambric fabric;
• small container for liquid;
• antifreeze in the amount required to fill the container.

The set of tools used to perform this work is quite small:

• wood hacksaw;
• screwdriver;
• pliers.

Step by step instructions

1. Let's start by cutting out a platform from a wide strip, the size of which should not exceed 50x120 mm. We use it as a stand for our device. In this case, the thickness of the stand of great importance does not have, however? You shouldn’t make it from 5mm plywood.
2. Now you need to take a 15x15 mm strip and cut it to the length of the existing thermometers. It will serve as the central pillar of the device.
3. A traverse is attached to this rack at a right angle.
4. Using small screws, we attach the thermometers to the traverse.
5. We wrap the alcohol-containing end of one of them as tightly as possible with cambric, so that the strip of fabric remains quite long to act as a wick. It will be immersed in a container of antifreeze.
6. A tripod, with thermometers attached to it, is attached to the stand. To do this, a hole is made in the middle of it, completely corresponding in size to the dimensions of the central pillar. The connection is made using PVA glue.

Summary of relative humidity data in the incubator

To determine the actual level of humidity in the ambient air of the incubator, it is practiced to use a special calibration table.

Video “Making a psychrometer with your own hands”

The video contains a story about how to make a psychrometer for an incubator with your own hands.

Humidity is a vital parameter for the normal development of embryos in the incubator. In the first week of laying eggs, its value should be 60–70%, in the second - no more than 40–50%, in the third it should be significantly higher - no less than 75%. This indicator can be measured with a special device - a hygrometer.

How does a hygrometer work?

A hygrometer or moisture meter is a device that allows you to determine the level of air humidity inside the incubator. To determine this value, the device is lowered into the container through a special hole for several minutes. Some time later, indicators appear on the sensor screen. With the incubator lid open, you should wait at least an hour for accurate data.

Important!Drops, dirt and direct sunlight negatively affect the operation of the moisture meter. For normal operation of the device, it should be protected from the negative influence of the external environment.

Moisture meters can be of different types. Depending on the principle of their operation, each of them has its own characteristics, certain advantages and disadvantages.

Weight

The operation of this device is based on a system of tubes interconnected. They are filled with a hygroscopic substance that absorbs air. Absolute humidity can be calculated thanks to the difference in weight before and after passing a certain portion of air. A special formula is used for this.

The disadvantage of this device is obvious - it is quite difficult for the average user to carry out the necessary mathematical calculations every time. The advantage of a gravimetric moisture meter is the high accuracy of its measurements.

Hair

This type of device is based on the property of hair to change length with changes in humidity. To determine this indicator, the hair in the incubator container is stretched onto a special metal frame.

Did you know?You can check the serviceability of the moisture meter upon purchase by holding the device in your palm for a few seconds. Under the influence of human body heat, the sensor readings should change.

It records changes using an arrow on a special scale. The main advantage of the method is simplicity. The disadvantages are fragility and low measurement accuracy.

Film

The operating principle of this device is based on the property of an organic film to stretch when high humidity and shrink when its level decreases. The film sensor works on the principle of a hair sensor, only here changes in the elasticity of the film under the influence of a load are recorded.

The data is displayed on a special display. Pros and cons this method identical to the characteristics of a hair moisture meter.

Ceramic

The operation of this device is based on the dependence of the resistance of a ceramic part, which consists of clay, kaolin, silicon and oxides of some metals, on air humidity.

Important!To increase the humidity in the incubator, the eggs are sprayed with water. However, this should only be done with waterfowl eggs.

The advantages of this type of device include their ability to accurately measure humidity over a wide range; the disadvantages are their considerable cost.

How to choose a hygrometer for an incubator

When making a choice, it is important to get as much information as possible about technical specifications device. When purchasing a moisture meter, the size of the incubator is also important - the larger it is, the more powerful the device should be.

When choosing a device, it is important to consider the following characteristics:

• for models with a remote sensor, the integrity of the cable and display should not be compromised;
• the pressure parameter can be relative (RH) and absolute (g/cub. m);
• if there is a need for a high-precision device, then an optical device is ideal for this;
• To place the device outside a living space, it is best to purchase a hygrometer with a high degree of protection from external factors; this indicator is measured on the IP scale.

The most popular devices are the “Tick-tick” and “Max” moisture meters. Electronic devices to measure humidity and temperature “Chick-chick” determine humidity from 20 to 90%, with an error of no more than 5%. Compatible with all household incubators. Max moisture meters measure humidity in the range from 10 to 98%. Power supply: disposable batteries.

Making this device at home is not particularly difficult. Difficulties arise when using it - it requires certain mathematical knowledge and care to avoid errors in calculations.

Tools and materials

To make a moisture meter you will need:

• two mercury thermometers;
• a board to which these thermometers will be attached;
• a small piece of fabric;
• thread;
• flask;
• distilled water.

Manufacturing process

To make a hygrometer with your own hands, you must perform the following steps:

1. Two thermometers are attached to the board parallel to each other.
2. Under one of them there is a flask with distilled water.
3. The mercury ball of one of the thermometers is carefully wrapped in cloth, which is tied with thread.
4. The edge of the fabric is lowered into the water to a depth of 5–7 mm. This way we get a “wet” thermometer.
5. The readings of both thermometers must be compared and air humidity determined using a temperature difference table.

Similar homemade device- a dubious alternative. Firstly, the readings obtained in this way have serious errors.

Secondly, to take readings you need to constantly open the lid of the incubator.

Which hygrometer will be chosen depends on the desires and capabilities of the poultry farmer. Today, they are offered a large selection of modern moisture meters: easy to use, with digital displays that measure not only humidity, but also temperature.

Did you know?Pine cones are a natural hygrometer. They open at low humidity and contract at high humidity.

Breeding chickens requires precision in instrument readings. Temperature and humidity values ​​are the most important in such a matter as incubation. In order to monitor the readings qualitatively, you need a device such as a psychrometer. It can be purchased in a store, but not every store has such a device, but you can make a psychrometer with your own hands. I’ll tell you what a psychrometer is and how to make a psychrometer for an incubator with your own hands in this article + thematic video.

What is a psychrometer

The “responsibilities” of the device include measuring air parameters. The device is used in poultry farming to accurately determine the humidity value. If the humidity is insufficient, the chicks will not be able to hatch from the shells and last stage During incubation, you can lose all the chicks.
The psychrometer is based on the physical ability of a liquid to evaporate. The result is a difference in temperature between the one shown by the thermometer in a dry environment and the one immersed in a humid environment.
Then use the table to find out the exact values.

Psychrometer for an incubator: how to make it yourself

To make your own psychrometer for an incubator, you need to purchase items such as:

• A pair of ordinary thermometers powered by alcohol, which are used to determine air temperature;
• Small wooden slats;
• Small screws;
• Fragment of a piece of cambric;
• Liquid container;
• Antifreeze.

The tools you will need are a screwdriver, pliers and a hacksaw.

The production of a psychrometer for the incubator begins sequentially, namely:

• A fragment of 50*120 mm is cut out of thin plywood or slats. This will be the stand for the device, so you don’t need to make it too thick, it won’t be convenient;
• We make a stand for the psychrometer; for this you need to cut out a fragment measuring about 15*15 mm;
• A traverse is attached to the rack at right angles, and thermometers are attached to it;
• You need to cut a strip 5-10 cm wide from cambric fabric and wrap it around one of the ends of the thermometer, leaving part of the strip free for immersion in antifreeze;
• Using glue, or better yet, screws, you need to secure the bar with thermometers to the central pillar.

In order to correctly use the psychrometer readings, you need the table that I have given below.

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A hygrometer is a moisture meter for an incubator that can be used to control the air humidity inside the incubator. But during different periods of incubation, humidity indicators should differ: in the first week - 65-75%, in the second - 40-50%, in the third - 75% (data for hatching chickens is indicated).

Devices that are used for household incubators are characterized by low cost - from 500 to 1000 rubles per product.

Operating principle

Electronic hygrometer

To measure humidity, lower an incubator hygrometer into the container through a special hole. It is fixed in a suspended state for 5-10 minutes.

After the specified time, humidity indicators should appear on the display of the moisture meter. If you open the incubator lid to lower the device, you need to wait about an hour to get accurate data.

For long-term and productive operation of the device, it is protected from falls and shocks, and the wire to which the sensor is connected is not pulled.

In order for the device to function properly, you must comply with temperature regime(from -40 to +70 degrees). You should also reduce the likelihood of dust, dirt and various liquids getting on the device.

The humidity sensor for the incubator works according to a specific algorithm:

• If the humidity level inside the container, which was set by the poultry farmer, has changed, the equipment is triggered and signals possible problems.
• After this, the farmer must study the humidity indicator, add or remove the amount of water in the incubator.
• After a few hours, you need to check the sensor readings again. You need to constantly monitor it so that there is a stable level of humidity in the chamber.

Types of hygrometers for incubators

Meet different types hygrometers, which have their own characteristics, individual type of operation, advantages and disadvantages.

The following varieties are distinguished:

1. Weight hygrometer for incubator. It consists of several combined tubes, inside of which there is a hygroscopic substance that absorbs moisture. Using this system, a small amount of air is drawn in and its humidity is determined.
2. Hair moisture meter. It is known that hair changes length when air humidity changes. Due to this, you can measure relative humidity - from 30% to 100%. The hair is pulled onto a metal frame, and if the humidity level changes, the data is transmitted to a arrow that moves along the scale.
3. Film air humidity sensor for incubator. Equipped with a special element made of organic film. When humidity increases, it stretches, and when it decreases, it contracts.
4. Ceramic. Its work is based on the dependence of the resistance of a ceramic part on air humidity.

How to choose the right hygrometer, what to look for

To choose a good hygrometer for an incubator, you need to study its technical data. First, pay attention to the pressure parameter, which can be relative (RH) or absolute (g/m3).

The choice of equipment also depends on the size of the incubators. If the container is small, for 40-50 eggs, you can use the simplest device. But for incubators with 100 or more eggs, it is recommended to buy more powerful hygrometers.

Typically, hygrometer readings are off by about 5%. If you need a more accurate device, then preference should be given to optical types. In order for equipment to last more years, when buying it, you need to look at its level of protection.

Measured on the IP scale. The higher its value, the more resistant the device is to dust, dirt and water.

Hygrometer models

Device name	Price	Advantages	Flaws
MAX-MIN	600 rubles	Equipped with a thermometer and a clock with alarm. An additional sensor can be connected.	There are no disadvantages.
Digital moisture meter with remote sensor.	250 rubles	Humidity measures from 10 to 99%. The kit includes an LR44 battery. Using the device you can work remotely.	The measurement error is too high - 7-8%. Moreover, the device quickly breaks down.
Stanley 0-77-030	6000 rubles	It has a shock-resistant case, an LCD display, and is small in size.	High cost.
HP-2GD	600-700 rubles	User-friendly interface, easy to use. Just click on the button and select the desired option.	Low quality case material.
Ryobi Phoneworks RPW-3000	2200 rubles	It is compatible with the operation of a smartphone; data can be received directly on the phone screen.	There are no disadvantages.
DC-206	300 rubles	The model has compact dimensions and can be used in small incubators.	The body is easily deformed under mechanical stress.
HTC-2	600 rubles	Has a built-in thermometer and clock.	No.
TA308	700 rubles	3 in one: humidity sensor, clock and thermometer.	High error of indicators: above 5%.

If you are wondering which is the best of all the options, then this title is occupied by the MAX-MIN device (3 in one). This is not just a humidity sensor. The plastic case contains a thermometer for the incubator, which shows the temperature values ​​as accurately as possible. The device is also equipped with a clock and alarm.

In addition, an additional MAX-MIN TH218A humidity sensor can be connected to it. By placing it directly inside the housing, you don’t have to worry about disturbing the internal microclimate in the incubator.

The sensor readings are as accurate as possible with an error of 1%. If the humidity level changes, an audible alarm will sound, allowing the poultry farmer to quickly become aware of any violations.

The thermometer lets you know if the temperature sensor is working correctly. After all, if deviations from the norm are too large and quite frequent, then there is a high probability of problems in its functioning. It needs to either be replaced or configured correctly.

An alarm clock is also an important and indispensable tool. Especially if you have to work with a manual incubator, when you need to turn the eggs yourself. By setting it to fire every 4-5 hours, you will never forget that you need to perform masonry manipulations.

The screen of the equipment is large, divided into three segments (for humidity, temperature and clock). All indicators are visible from afar, highlighted bright color. Therefore, you don’t have to approach the incubator every time, because data on its operation can be viewed from a distance. I am especially pleased with the cost of the device - only 600 rubles.

How to make a hygrometer with your own hands

And although a hygrometer for an incubator is inexpensive, you can make it yourself. A DIY moisture meter for an incubator gives more accurate readings than its store-bought counterparts.

To make a homemade device, you need:

• Take two mercury thermometers to measure air temperature and water. You also need to take a board on which both thermometers will fit.
• Both thermometers need to be attached to the board parallel to each other. A vessel with distilled water is placed under one of them.
• The mercury ball of one thermometer must be carefully wrapped in a cloth without contacting it. Then the fabric should be tied with thread, not too tightly. This thermometer is called wet, and the second is called dry.
• The edge of the fabric should be lowered into water by 5-7 mm.
• The indicators of both thermometers are compared with each other and using the table they find out the relative air humidity in the incubator.

Sometimes you have to spray the eggs with water to increase the humidity in the chamber. But this technique should only be used in the case of waterfowl eggs. For the rest of the embryos, a humidity of 50-60% is enough. You can calculate the humidity indicator using the table below.

Dry thermometer data	Difference in thermometer readings in degrees
	0	1	2	3	4	5	6	7	8	9
	Relative humidity percentage
15	100	92	80	71	61	52	44	36	27	20
16	100	90	81	71	62	54	45	37	30	22
17	100	92	81	72	64	55	47	39	32	24
18	100	91	82	73	65	56	49	41	34	27
19	100	91	82	74	65	58	50	43	35	29
20	100	91	83	74	66	59	51	44	37	30
21	100	91	83	75	67	60	52	46	39	32
22	100	92	83	76	68	61	54	47	40	34
23	100	92	84	76	69	61	55	48	42	36
24	100	92	84	77	69	62	56	49	43	37
25	100	92	84	77	70	63	57	50	44	38

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Raising poultry is a painstaking and difficult task. In order for a chick to emerge from an egg, it is necessary to create special conditions for the development of the embryo for several weeks. A psychrometer for an incubator is a device that will help you monitor the most important parameters. No owner can do without it.

Functions

Breeding poultry under incubation conditions is very popular, both in private farming and in mass production. Every owner knows that a chicken can hatch from an egg only if all the parameters are met.

Scheme of a homemade psychrometer

The main points in this matter are:

• temperature;
• air humidity.

If these indicators are lower or higher than standard, then even the most modern technologies can't turn an egg into a bird. Therefore, it is very important to monitor the humidity and heat in the middle of the incubator. This is where a psychrometer comes in handy.

This device is used on the farm to measure air parameters. In most cases, its purpose is to determine the percentage of air humidity.

But, with a complicated design, it is possible to additionally set the temperature in the middle of the incubator.

The device operates on the basis physical properties– evaporation of liquid. Having two thermometers, one of which is immersed in water, and the second remains dry, two indicators are determined.

Using a special table compiled by specialists, the humidity of the air in the incubator is directly displayed. That is, a psychrometer is a special device that can calculate air humidity using the difference in the readings of two thermometers.

In practice, using this device is very easy and convenient. A psychrometer for an incubator can be purchased in specialized stores. There is also an option self-made device.

The most popular device models and their characteristics

Species

Devices available on the modern market can be divided into three groups, using their operating principle as a criterion:

• aspiration;
• stationary;
• remote.

An aspiration psychrometer for an incubator is characterized by the presence of two thermometers, which are located in a special frame. This ensures that the device is less subject to negative influence and damage.

Air from the incubator is constantly blown onto the thermometers themselves with the same power using a special fan. As a result, the temperature is determined on thermometers. One of the advantages is the accuracy of the data, but the main disadvantage is the high price.

Stationary devices are located in the meteorological booth. It, in turn, is attached to the incubator using a tripod. The calculation of indicators occurs due to the circulation of air flow through the booth.

The disadvantage of the device is that a humidified thermometer can change data depending on the strength of the air flow, which is not the case in the previous version, since it is constant there. On the plus side, it is very easy to use and easy to repair.

Remote technologies involve the use of:

• resistance thermometers;
• thermistors.

The main characteristic of the devices is that the results are displayed on a part of the device outside the incubator. At the same time, in the middle there is a special sensor that constantly measures indicators.

The main advantage is the accuracy of the indicators. The errors of these devices are minimal, and the results are displayed to hundredths. The disadvantages include the high cost and complexity of repairs in the event of a breakdown.

Popular models

The most popular models among buyers from the types discussed above today are:

As we see, the most cheap option- a stationary device, and the most expensive is aspiration. But the high cost is justified by the high accuracy of the results.

Dear colleagues,

This year, we at NPK Relsib have significantly increased sales of our Ivit-M temperature and relative humidity meters and EClerk-M autonomous temperature and humidity recorders (dataloggers). This is certainly good. But at the same time, the number of written and oral complaints that our devices are lying has increased significantly. And they lie shamelessly. It is significant that the number of such claims increases significantly in winter and drops to zero in the warm season. At the same time, everyone compares the readings of our instruments with the well-known psychrometric hygrometer VIT-2.

The cup of patience ran out, and at the same time there was a realization that it was impossible to do without a detailed explanation of why it was necessary to stop comparing modern accurate relative humidity meters with an ancient psychrometer. Imagine the situation that in the workshop of a pharmaceutical enterprise, where VIT-2 had been hanging on the walls for decades and where the regulations established the requirement to strictly maintain air humidity in the range of 30...50% relative, suddenly, after installing the EClerk-M-RHT recorder, it turned out that humidity is actually 15%. Naturally, the first reaction - EClerk-M - is lying and you need to return it to the manufacturer!

Your instruments not only have a large error, but they lie mercilessly! They show that in our hospital the relative humidity is 5...10%. But people can’t live in such humidity!

The true story of one pulmonary hospital

Apparently, it’s already in our blood to believe without looking back in Soviet glass instruments, mercury thermometers, and VIT psychrometers. But if faith in a mercury thermometer is quite understandable and justified, and it is strengthened because of, then in the case of VIT-2 everything is completely different.

The temperature and relative humidity measuring instruments produced by our company have passed a full range of tests in an independent accredited laboratory and are included in the State Standard. register of measuring instruments. Before leaving production, devices undergo state verification for compliance with accuracy indicators on certified equipment and in the presence of the State. verifier. There is no reason not to believe the readings of our instruments. Almost all devices we produce have a measurement range rel. humidity 0...98% rel. and accuracy ±3%. The devices are equipped with automatic adjustment of rel. readings. humidity in a wide temperature range from -40 to +80°C.

Well, now let's carefully read the documentation for the psychrometric hygrometer VIT-2. In accordance with the passport for the device, the range for measuring relative humidity depends on the room temperature:

The absolute error limit of the device at an air aspiration (blowing) speed of 0.5...1 m/s is equal to ±5...7%, depending on the temperature. In the instructions for the device (clause 4.5.) we read: “ The psychrometric table installed on the base of the hygrometer is valid for a certain speed of vertical air flows." And then we read clause 4.6.: “ Before measuring relative humidity, measure the aspiration rate directly under the hygrometer. Measure the aspiration rate using a vane anemometer U5 GOST 6376-74. It is possible to use the previously produced anemometer ASO-3, type B, GOST 6376-52. The procedure for carrying out measurements is in accordance with the passport for the anemometer».

So! It turns out that the VIT-2 hanging on the wall can only be trusted if you approach it with a fan and an anemometer!! And the ASO-3 anemometer costs not 350 rubles, but more than 8.0 thousand rubles. And only in this case, if you set up the air flow properly and comply with all other conditions necessary for measurement and detailed in the instructions for the VIT, do you have the theoretical ability to determine the rel. humidity with an accuracy of about 6%.

It turns out that the consumer is being deceived! Most people don't understand this. At the same time, most consumers are satisfied with this. The VIT-2 device is inexpensive. You can forget that for correct measurements it is necessary to provide airflow with a verified device.

And here we see the picture. Everywhere where they are supposed to, VIT-2 hygrometers hang on the walls and at the same time: in libraries paper dries out and collapses, in museums picture frames crack and varnish becomes unusable, asthmatic children cough in kindergartens, microcircuits break through in electronic factories, etc. .d.

Maybe we won’t close our eyes anymore and take such an important parameter as humidity seriously?

Last winter I dealt with air humidity and humidifiers. By spring, the Captain still managed to convey to me the need to measure humidity if I was going to regulate it. I had one hygrometer, however, long before that. There was no understanding whether it showed the humidity in the house or on the top of Kilimanjaro. I chose and ordered two more in the spring. I chose with different sensors. A six-month overall positive experience - below the cut.

My first hygrometer is a DHT11 sensor attached to an Itead Sonoff TH WiFi dongle. Him, today we are talking about others. The DHT11 sensor does not have a reputation for being accurate. But, looking at the winter humidity figures around 18%, I was still perplexed - well, it can’t be that much! I decided to choose a couple of hygrometers with different sensors and compare. The idea of ​​a psychrometer consisting of dry and wet thermometers was left as a last resort as it was too gimmicky.

Conclusions after six months of operation

1) All three sensors give very consistent humidity readings - the difference is usually no more than one digit, very rarely two. Despite the fact that the passport accuracy is +-5 percentage points.
2) In winter, without a humidifier, my house is really 18%:((In the warm season - 30-50%, in prolonged rain outside up to 60%. Moscow, concrete house, double-glazed windows.
3) Air humidity is a very inert thing. If you turn on the humidifier for the first time in winter, then for a couple of days nothing seems to happen. It looks like water is soaking into the walls and furniture. And only after a few days it grows noticeably.
4) When turned on daily, one air humidifier at 250 g/h in a closed bedroom reaches up to 60% overnight, which is at the upper limit. At open door There’s literally not enough of it for the whole apartment. Two humidifiers for 600 in total somehow cope. (When we leave, we always turn off the humidifiers. And not only them.)
5) B different parts room humidity can easily differ by 5%. A meter from a working humidifier - and by 20%. Therefore, by the way, I think a humidifier with a built-in hygrometer is a bad idea.
6) The inertia of the sensors is quite high, about an hour to settle down. Although the readings begin to change when transferred to another place almost immediately. The option with an external sensor is slightly less inert.

Delivery and packaging

Both orders were on March 05, 2017, delivered in 4-5 weeks, there were no tracks. I don’t remember the packaging, it was quite sufficient.
At the time of purchase, both had free shipping, now both have paid shipping. But there are a lot of options on Ali.

Appearance

The main body of the hygrometers itself is the same. Involves cutting into a flat surface. But I still haven’t decided whether it’s necessary.
Power supply: 2 pcs LR44 batteries. The red one came without batteries included. White - with batteries. Now something could have changed. I haven’t changed the batteries in six months, both work continuously.

UPD 100% humidity

Comrades expressed legitimate doubts in their comments. I answer


It would be a shame for me to make less than my 30%, but in the spring it was 18%. Today, a meter from the humidifier it was 47%
So it definitely works.

Specifications

White, according to the seller
Humidity measurements: 10% RH-99% RH
Humidity Accuracy: ±5%
Humidity Display Resolution: 1% RH
Temperature Measuring Range: -50Celsius ~ 70 Celsius
Temperature Accuracy: ±1 Celsius
Temperature Display resolution: 0.1 Celsius
Power supply: 2x1.5V Button LR44 batteries (Included)
Dimensions: approx. 4.8x2.8x1.5cm/1.89x1.10x0.59""
LCD Display Dimensions: Approx. 3.6x1.7cm/1.42x0.67""
Cable length: approx. 1.5 m/59.06""
Probe length: approx. 6cm/2.36""

Red, according to the seller
Measuring range: Temperature -50c-+70c(-58f-+158f) Humidity 10%-99% RH
Measurement Accuracy: Temperature ± 1s(± 2f) Humidity ± 5% RH
Display resolution: Temperature 0.1c (0.2f) Humidity 1% RH
Operating Voltage: 1.5V, two button cell size LR44(not included)
Dimensions (L*W*D): 6 x 4.8 x 1.5cm/2.36" x1.89" x 0.59" (approx)
LCD Size: 3.5 x 1.6cm/1.38" x 0.63" (approx)

According to my measurements
Both have a seat size of 45 x 25
Dimensions, white excluding wire 48 x 29 x 17
Dimensions, red 61 x 57 x 17

White, sensor
length of the wire itself, excluding the sensor - 150 cm
sensor mounting diameter ⌀ 9.2 mm,
landing cylinder length 36 mm
dimensions ⌀14 x 61

Conclusions

Although the sensors have a certified accuracy of plus or minus half a bast shoe (5 pp), they provide very good inter-instrument compliance, at the level of 1 pp. I am ready to recommend any of them. Or rather, like during the time of great geographical discoveries, when there were THREE chronometers on the ship. So that if one breaks, it is clear which one. That is, it is worth having three different hygrometers, especially since they cost pennies, and different places Apartment humidity may vary markedly. I'm planning to buy +9 Add to favorites I liked the review +27 +39

A hygrometer is a device for measuring humidity - everyone knows this. It is also well known to everyone that lately it has become a permanent, and for many, a necessary (not just a decoration) attribute of most saunas and baths.

Experienced lovers of bath procedures say: “The best hygrometer is the ears!” However, then they usually add: “... and experience.” Of course, experience is a great thing, but a beautiful and reliable device on the wall of a modern steam room (sauna) never hurts.

Most of the numerous modern hygrometers can be divided into three main groups.

1. Electronic hygrometers.

Very often, these devices are built into control panels for steam generators and humidifiers. The reliability and accuracy of operation of such products largely depends on the circuit design and the quality of the components.

2. Psychrometric hygrometers.

The principle of operation of devices of this type is based on changing the difference between the readings of a wet and dry thermometer, which depend on the humidity of the air in the room; they then directly measure the humidity using special psychrometric tables. Temperature is measured based on dry bulb readings.

Such hygrometers are rarely used in sauna baths.

3. Mechanical hygrometers.

The principle of operation of such devices is based on the property of degreased hair to change its length when the humidity of the surrounding air changes. When the length of the hair changes, the pulley mechanically connected to it rotates, and the end of the arrow moves along the scale (see Fig. 1).

Rice. 1. Diagram of a hair hygrometer.

Today, instead of good old hair, a specially treated synthetic thread is usually used as a sensing element. Mechanical hygrometers operate quite reliably over a wide temperature range of at least +10°C to +120°C), measuring humidity fairly accurately in the range from 30% to 100%. Such mechanisms are now installed in the vast majority of relatively inexpensive bath hygrometers and combined thermometer-hygrometers. Most often, bath hair hygrometers and bimetallic thermometers-hygrometers operate stably and provide fairly reliable readings with quite acceptable - from a practical point of view - accuracy.

However, like anyone mechanical device, the hair hygrometer does not like rough handling, especially strong shaking or sharp blows. Sometimes such a device can begin to completely indecently overestimate or underestimate readings, even just after a long stay in severe frost.

If it is possible to compare the readings of a hair hygrometer with the readings of a reference device, then if there are serious discrepancies, the readings of a mechanical hygrometer can be easily corrected. This can be done using a screwdriver through the hole on the back cover. You should insert a screwdriver into the slot of the adjusting screw on the support of the measuring mechanism and, turning it carefully, move the arrow to the desired reading on the instrument scale. Usually this is enough to restore the functionality of the hygrometer.

If it is not possible to compare the readings of a hair hygrometer and a known working precision device, then you can try to make adjustments using another method available at home. It should be borne in mind that it is best to check the operation of a thermometer-hygrometer at a temperature as close as possible to what it would usually be in a steam room.

To check and adjust, you will need: a kettle, a transparent plastic bag, a stand for the device being tested to place it at the level of the kettle spout (for example, a shallow saucepan). Next we proceed as follows. We place the device in a bag and make a small hole in the bag for steam to escape (photo 1). We connect the bag to the spout of the kettle and secure this connection with threads or an elastic band (photo 2). We put it all on the stove and light the fire (photo 3).

After some time, the water in the kettle will boil, the scales will fog up, the temperature will begin to rise, and the thermometer needle will set around 95-100°C, the hygrometer needle will also begin to deviate and reach its maximum (photo 4).

If within 3-5 minutes the hygrometer needle does not change its highest position, we can assume that the maximum point has been reached. The thermometer needle should show 95-100C, that is, a temperature close to the boiling point of water. If the value is different, for example, 80°C, you need to adjust the thermometer readings using a screwdriver through the hole on the back cover. This can be done directly through the package. The most important thing is not to get scalded!

If necessary, the position of the hygrometer needle is also adjusted, setting it to a value close to the maximum - 95-100%.

Now you can carefully remove the device from the bag, dry it and... go to work. The photo at the beginning of the article shows the readings of a household electronic thermometer-hygrometer and a hair bath thermometer-hygrometer tested using a kettle. The picture was taken the next day after checking, adjusting and drying the device for 24 hours - the readings of both devices are almost completely identical. Thus, this method allows you to quite accurately adjust the hygrometer at temperatures close to operating temperatures.

But the main thing is not to forget that no matter what precise device is used, your well-being is the most important criterion. A bath should bring health and joy!

A mechanical (psychrometric) hygrometer is a device very sensitive to shaking, sudden temperature changes and vibration. Under the influence of these factors, the accuracy of its readings can be significantly reduced. Even if the device initially showed the correct humidity level, when transporting or moving the hygrometer to a room with different conditions, as well as before purchasing in a store, EKSIS JSC recommends testing the device again. Checking the device for correct readings is called calibration.

In order to correct the readings of the device, a special mechanism in the form of a screw is provided in the body of most models. As it rotates, the position of the arrow will change. If there is no such mechanism (which often happens in cheap models), the device must be completely disassembled.

H2: Calibration Methods

In order to achieve accurate readings, it is necessary to place the device in an environment with a previously known air humidity. If the hygrometer correctly displays microclimatic conditions, then it does not need to be calibrated. There are three methods that are used most often:

• Verification with the configured device. If you have another, already calibrated humidity measuring device, install a new hygrometer next to it. When the readings become stable, adjust the arrow of the device being tested to the same value as the arrow of the first. This is the most quick way, but it is only effective if you completely trust the accuracy of the measurements of the old hygrometer.
• Calibration in a completely humid environment. This method involves placing the hygrometer in a closed environment whose humidity is known in advance. To do this, wrap the device in a damp cloth and place it in a plastic bag. According to the laws of physics, in a confined space moisture will evaporate until the maximum humidity is reached. In this case it is approximately 96%. Keep the device in the bag for one hour, then remove it and set the arrow to this value. For this method, the speed of adjustment is very important - as soon as the device is removed from the humid environment, it will quickly begin to change readings, adapting to the conditions of your room. This usually happens within one minute. If you do not have time to calibrate the device during this time, the procedure will have to start again.

• Using table salt. This method, compared to the previous one, is more accurate. It is known that a closed space containing a saturated brine solution has a humidity of 75%. To calibrate a hygrometer using this method, you should perform a number of steps: take a sealed container, place a small container filled with table salt there, add water so that it is completely absorbed, and place the device under test next to it. After eight hours, set the hygrometer needle to 75%.

It is worth noting that the described actions are carried out only with mechanical measuring devices. Electronic hygrometers do not need to be calibrated because their accuracy does not change over time.