How to use a barometer to find out what pressure. Barometer - a device for measuring atmospheric pressure. Features of data interpretation

Barometer- This is a measuring device that is designed to determine the pressure of atmospheric air. In addition to meteorological applications, the barometer is used for environmental monitoring (for example, to certify workplaces) or in aviation (to determine flight altitude above sea level).

Figure 1. Aneroid barometer

For the first time, the barometer was invented and described in the work "Opera geometrica" ​​in 1644 by a scientist from Florence (Italy) Evangelista Torricelli. It was a liquid mercury barometer, the pressure of which was measured by the height of the mercury (liquid) column in a tube sealed at the top and placed in a vessel with mercury (liquid) at the bottom end. On the day when Torricelli was experimenting with his mercury barometer, the weather was calm and sunny, and the column of mercury stopped at 760 mm. Since then, a pressure of 760 mmHg has been normal. Mercury and liquid barometers are the most accurate and are still used in meteorological stations. Their disadvantage is fragility, insecurity and large size.

In 1844, the French engineer Lucien Vidi, using the research of a German mathematician and physicist of the 17th century. Gottfried Wilhelm Leibniz, designed a fundamentally new, liquid-free barometer, which was called an aneroid barometer (from the Greek "aneros" - not containing moisture). Barometers built on the basis of the L. Vidi barometer, at the moment, are the most common.

Generally, barometers, depending on the principle of operation can be mercury, liquid, aneroid or electronic.

- liquid barometer- a device that uses the principle of balancing the weight of a column of liquid with atmospheric pressure.

- mercury barometer- atmospheric pressure, in which, you can measure the height of the mercury column on the scale attached next to it.

- a device, the principle of which is based on changing the dimensions of a metal box filled with rarefied air, under the influence of atmospheric pressure. Such barometers are reliable and small in size.

- Electronic barometer– this type of barometer works on the principle of converting the linear dimensions of a traditional aneroid pressure box into an electrical signal and further processing this signal by a microprocessor. If, instead of an aneroid box, a strain gauge is used, then the measured pressure is perceived by this sensitive element, is converted through its deformation, into a change in the electrical resistance of the strain gauges of the strain gauge transducer.

However, since the topic of this article is "Aneroid Barometer", let's return to this type of pressure measuring instruments and consider them in more detail.

So, this is a device that is designed to measure atmospheric pressure mechanically. Structurally, the aneroid consists of a round metal (nickel-silver or hardened steel) box with corrugated (ribbed) bases, in which, by pumping out air, a strong vacuum is created, a return spring, a transmission mechanism and an arrow pointer. Under the influence of atmospheric pressure: its increase or decrease, the box, respectively, either shrinks or unbends. At the same time, when the bellows box is compressed, the upper flexing surface begins to pull the spring attached to it down, and when the atmospheric pressure decreases, the upper part, on the contrary, bends and pushes the spring up. To the return spring, by means of a transmission mechanism, is attached an arrow pointer, which moves along a scale calibrated in accordance with the indications of a mercury barometer (Figure 2). It should be noted that usually, in practice, several (up to 10 pcs.) series-connected thin-walled corrugated boxes with a vacuum are used, which increases the amplitude of the needle movement along the scale.

Figure 2. Design of the Aneroid Barometer.

Aneroid barometers, due to their small size and the absence of liquid in the design, are the most convenient and portable; they are widely used in practice.

Unfortunately, barometers are affected by ambient temperature and change in spring tension over time. Therefore, modern aneroid barometers are equipped with an arc-shaped thermometer, or the so-called compensator, which is intended to correct the instrument readings for temperature.

In general, to obtain the true value of atmospheric pressure, the readings of an aneroid barometer need various corrections, determined by comparison with a mercury barometer. There are three corrections to aneroids:

Scale correction - this correction depends on how unevenly the aneroid barometer reacts to pressure changes in different parts of the scale,

Correction for temperature - is determined by the relationship between temperature and elasticity of the aneroid corrugated box and spring,

Additional correction - is determined by the change, over time, of the elasticity of the aneroid corrugated box and spring.

The body of an aneroid barometer is usually made of precious woods such as walnut, oak, beech, cherry or mahogany. Such barometers are no longer just instruments for measuring atmospheric pressure, but interior items. However, to reduce the cost of the entire structure, and make it more practical, the aneroid body can be made of plastic or metal.

Aneroid barometers represented by models:

- BAMM-1 is a barometer designed to measure atmospheric pressure on the ground and indoors. It is included in the State Register of Measuring Instruments of the Russian Federation, therefore it can be used for attestation of workplaces.

- M-67 is the most accurate and unpretentious barometer. Due to its design features, it is able to operate at temperatures from -10 to +50 ° C (Figure 3).

- M-110 - barometer for industrial use, included in the State Register of Measuring Instruments.

- BB-0.5M - wall-mounted household barometer. Ideal for approximate measurement of atmospheric pressure.

- BR-52 - a school aneroid barometer used as a teaching aid and for experiments.

Figure 3. Model M67 barometer.

For more accurate or longer measurements, as well as for verification of related instruments at weather stations, meteorological posts and laboratories, other instruments are used. They can be either digital or mechanical. For example, the BOP-1M barometer, being an exemplary portable barometer, as a reference measuring instrument, is intended for verification of barometers of various designs and general industrial instruments that measure atmospheric pressure.

BRS-1M is a working network barometer, designed to accurately determine the absolute air pressure, has a digital RS232 interface for connecting to a computer.

Meteorological barograph M-22A is a device that is designed to determine and graphically record atmospheric pressure values ​​both inside and outside the premises, for a certain period of time (Figure 4.).

Figure 4. M-22A barograph

Automated digital barometer MD-13 is used at weather stations for long-term (up to 1 month) measurement of atmospheric pressure with the ability to transfer measurement results to a computer.

Barometers can be aneroid and mercury. The word "aneroid" means "liquidless". The principle of operation of such a barometer is quite simple: changes in atmospheric pressure lead to a change in the geometric dimensions of the aneroid, as a result, the arrow on the scale moves. Such barometers do not contain dangerous elements, therefore they are suitable for use on a hiking trip.

In addition to aneroid, there are also devices in which mercury is used to measure atmospheric pressure. Under the action of atmospheric pressure, the height of the mercury column changes. The readings of these barometers are more accurate; these are the instruments used at meteorological stations. Mercury and its vapors are dangerous to humans, therefore, such devices are not used in conditions.

On sale you can find electronic barometers, as a rule, they are part of home weather stations. Such complex instruments also measure a number of other quantities (for example, air temperature and humidity) and make it possible to fairly accurately predict the weather for the near future. Digital devices are less sensitive to shaking, so they are good for sea travel.

Using the barometer

An aneroid barometer is easy to use. You need to look at what value the arrow of the device points to. There are zones on the barometer scale, which are designated as “dry”, “clear”, “variable”, “rain”, “storm”, as well as divisions indicating absolute values. If the pressure decreases, precipitation is expected, if it rises, it will be clear. As a rule, the barometer has two arrows - one is movable, it is connected to the aneroid box, and the second can be rotated. If it is combined with an arrow showing the value of atmospheric pressure, after a while you can observe in which direction the movable arrow will deviate.

Normal atmospheric pressure is 760 mm Hg. Art. at an air temperature of 15°C at the so-called sea level. Home barometers can measure its value in the range of 700-800 mm Hg. Art. at an altitude of no more than 300 m above sea level. A drop in pressure means worsening weather conditions, approaching rains or snowfalls. Low pressure areas are called cyclones. Anticyclones are areas of high pressure, their approach means the onset of good weather. The barometer is adjusted if its readings differ from the readings of the local weather station by more than 8 mm Hg. Art. For these purposes, an adjustment screw is provided, located in the rear of the case. When setting up, you need to rotate it at an angle of no more than 45 degrees.

Since childhood, we are used to hearing about high or low atmospheric pressure, but did not understand how to determine it, and why it is high or low. In today's article, we will take a closer look at the device, the purpose of which is to solve the problem of determining these parameters.

Peculiarities

An aneroid barometer is a household appliance designed to mechanically monitor atmospheric pressure differences. This device is very sensitive and is able to show the pressure difference even when taking an elevator. When monitoring its performance, you can notice certain changes when the weather changes. Thus, many changes can be predicted: before the weather deteriorates, atmospheric pressure decreases, and before the arrival of a clear day it increases.

Before taking readings from the device, it is necessary to take into account the height of its location above sea level. The higher the device is, the lower the atmospheric pressure will be. When ascending to a slight height, the readings will be reduced by 1 mm Hg. Art. approximately every 12 meters of ascent.

The aneroid barometer has one drawback - it is effect of air temperature on the spring. The difference in temperature readings causes the metal to contract when cold and expand when heated, without changing the pressure of the atmosphere. To correct for temperature, modern models are equipped with compensating thermometers.

Thanks to them, corrections can be made to the readings of the device.

Principle of operation and device

The described device consists of a metal round box made of hardened steel (sometimes nickel silver). The ribs of this part have a corrugated coating. This is necessary to make the structure rigid, since a highly rarefied medium is created inside by evacuation. In such conditions, the return spring and the arrows of the mechanism are constantly located.

When the pressure of the atmosphere acts on the walls of the device, a narrowing or expansion occurs. During such compression, the upper platform begins to sag and pull the spring attached to it down. When the load decreases, the upper half of the platform, on the contrary, bends upward and puts pressure on the spring. An arrow is fixed to the return spring part through the return mechanism, which moves along the scale of values.

To obtain the most accurate readings, it is necessary to make comparisons with the values ​​​​of a mercury barometer. There are 3 main corrections for mercury:

• on a scale, namely, the unequal response in different zones of the scale;
• by temperature– the error in the physical change of the metal when exposed to temperature is taken into account;
• other errors which are due to changes in the elasticity and rigidity of metal parts over time.

The scale is lined according to the values ​​of the mercury barometer. Using the barometric formula, you can calculate the height at which the instrument is located. By measuring the pressure of the atmosphere at the upper and lower measured point, it will be possible to determine the difference in pressure and convert it to meters. This measurement method is called barometric leveling. In this way, the height of the observation point is calculated in GPS devices.

Varieties

This device was first described in 1644 by Evangelist Torricelli, an Italian scientist. This device turned out to be the first barometer on mercury (liquid), the measurements of the values ​​​​in which were made in accordance with the height of the mercury column. The scheme of such a device is very simple. The glass pillar has a sealed top, and its bottom is immersed in a container with mercury. During the experiment, the weather was very good and clear. Then the mercury column froze at a height of 760 mm, which was subsequently taken as the optimal indicator.

Mercury models are used in our time at meteorological stations, because they have high accuracy, and with it the disadvantages in the form of insecurity, fragility of the design and bulkiness.

Today it is a control device by which all other devices are configured.

In 1844, the French engineer Lucien Vidy, based on the work of the physicist and mathematician Gottfried Wilhelm Leibniz from Germany, created another type of barometer that works without liquids. Later this "liquidless" device was called an aneroid barometer.

The aneroid version is by far the most common among household versions.

There are 4 types of such devices:

• liquid- this device uses the principle of equalizing the mass of the liquid column with the pressure surrounding it;
• mercury- atmospheric pressure is measured due to the height of the mercury column with a scale attached to it;
• aneroid barometer - the device functions on the principle of changing the size of a box with a discharged medium inside, under the influence of atmospheric pressure, its size changes;
• electronic barometer- this subspecies of the barometer uses the conversion of changes in the box of an aneroid barometer into a digital signal or with the help of a strain gauge, which is very sensitive, and a change in atmospheric pressure is perceived as a deformation, as well as a change in resistance.

Consider models of aneroid barometers.

• BAMM-1. This device is designed to measure the atmospheric effect while on the ground and indoors. This type is included in the State Register of Measuring Instruments and can be used to check jobs.

• M-67. The device has more accurate readings, and with its design features, the temperature range of operation is from -10 to +50 C.

• M-110. This barometer is designed for industrial use.

• BB-0.5M. A household appliance designed to be placed on the wall is well suited for weather-dependent people to monitor changes in atmospheric pressure.

• BR-52. The school aneroid barometer is designed in such a way that it can be used for experiments.

How to use?

When taking readings from the described device, it must be understood that it does not give a 100% guarantee in weather changes or in the amount of precipitation. It will not show which atmospheric front came to the territory being checked. Meteorologists use many additional instruments and photographs to determine the weather.

The device itself gives only an idea of ​​​​in which direction the weather conditions will change. It will show whether the weather will be changeable for the worse or for the better. The device is necessary for weather-dependent people to control their own well-being:

• in the cold winter season with a decrease in pressure, frosts can be expected, and with an increase, warming and possible snowfall are expected;
• in summer time an increase in pressure indicates the approach of hot and dry days, and a decrease warns of the approach of rain.

The rate of change of values ​​is also regarded as the most probable change in the weather. And when the pressure decreases gradually, then the weather will worsen during the day. Possible wind and precipitation. If the arrow falls sharply, strong winds and heavy rain with thunderstorms should be expected.

A sharp drop in the arrow can still tell about its beginning in about 2 hours. When the arrow froze and keeps at a certain level, then you can count on a decrease in wind and a cessation of precipitation.

In order to correctly understand the readings of the device, you need to constantly monitor it. In good weather, you can take all the values ​​2 times a day, and in bad weather you need to control the device every 2-3 hours.

After the advent of the electronic barometer, the need for its adjustment disappeared, but there are still classic options on the market with the need for regular adjustments.

They are loved for their presentable appearance and the absence of the need to replace batteries.

Barometers can be aneroid and mercury. The word "aneroid" means "liquidless". The principle of operation of such a barometer is quite simple: changes in atmospheric pressure lead to a change in the geometric dimensions of the aneroid, as a result, the arrow on the scale moves. Such barometers do not contain hazardous elements, therefore they are suitable for use in, on a hiking trip.

In addition to aneroid, there are also devices in which mercury is used to measure atmospheric pressure. Under the action of atmospheric pressure, the height of the mercury column changes. The readings of these barometers are more accurate; these are the instruments used at meteorological stations. Mercury and its vapors are dangerous to humans, therefore, such devices are not used in conditions.

On sale you can find electronic barometers, as a rule, they are part of home weather stations. Such complex instruments also measure a number of other quantities (for example, air temperature and humidity) and make it possible to fairly accurately predict the weather for the near future. Digital devices are less sensitive to shaking, so they are good for sea travel.

Using the barometer

An aneroid barometer is easy to use. You need to look at what value the arrow of the device points to. There are zones on the barometer scale, which are designated as “dry”, “clear”, “variable”, “rain”, “storm”, as well as divisions indicating absolute values. If the pressure decreases, precipitation is expected, if it rises, it will be clear. As a rule, the barometer has two arrows - one is movable, it is connected to the aneroid box, and the second can be rotated. If it is combined with an arrow showing the value of atmospheric pressure, after a while you can observe in which direction the movable arrow will deviate.

Normal atmospheric pressure is 760 mm Hg. Art. at an air temperature of 15°C at the so-called sea level. Home barometers can measure its value in the range of 700-800 mm Hg. Art. at an altitude of no more than 300 m above sea level. A drop in pressure means worsening weather conditions, approaching rains or snowfalls. Low pressure areas are called cyclones. Anticyclones are areas of high pressure, their approach means the onset of good weather. The barometer is adjusted if its readings differ from the readings of the local weather station by more than 8 mm Hg. Art. For these purposes, an adjustment screw is provided, located in the rear of the case. When setting up, you need to rotate it at an angle of no more than 45 degrees.

The invention of the barometer is universally credited to Evangelisto Torricelli in 1643. However, historical documents say that the first water barometer was unknowingly built by the Italian mathematician and astronomer Gasparo Berti between 1640 and 1643.

Gasparo Berti's experiment

Gasparo Berti (circa 1600 - 1643) was most likely born in Mantua. He spent most of his life in Rome. He became famous for the experiment in which he, without knowing it, built the first working barometer. He also has works in mathematics and physics.

In 1630, Giovani Battista Baliani sent a letter to Galileo Galilei saying that his siphon-type pump could not lift water more than 10 meters (34 feet). In response, Galileo suggested that vacuum lifts the water, and the force of the vacuum cannot hold more water, just as a rope cannot support too much weight. According to the ideas prevailing then, a vacuum could not exist.

Galileo's ideas soon reached Rome. Gasparo Berti and Rafael Maggiotti developed an experiment to test the existence of a vacuum. Bertie built an 11-meter pipe, filled it with water and sealed it on both sides. Then one end was immersed in a container of water and opened. Part of the water flowed out, but about ten meters of the pipe remained filled, as Baliani had predicted.

The space above the water had to look for explanations. Explanations within the framework of the prevailing theory that rejects the vacuum, there were as many as two. According to the first, water gives birth to "spirits". "Spirits" fill space and displace water. According to the second, more common argument proposed by Descartes, the space above water is filled with ether. Ether is such a thin substance that it can penetrate through the pores in a pipe and displace water.

Explanation of Evangelisto Torricelli

Evangelisto Torricelli, a student and friend of Galileo, dared to look at the problem from a different angle. He suggested that air has weight, and that it holds the water in the pipe at a level of about ten meters. Previously, it was believed that air is weightless and its thickness does not exert any pressure. Even Galileo accepted this statement as an infallible truth.

If the assumption about the weight of air is correct, a liquid heavier than water should sink lower in the pipe than water. Torricelli shared this prediction with his close friend Vincenzo Viviani and suggested using it as a

In the seventeenth century, mankind became aware and proved the fact that air has a certain weight. The assumption of its pressure on various objects was proved with the help of a special device - a barometer. It will be discussed in this article.

A device that measures air pressure

Let's start with a definition. A barometer is a device for measuring a certain amount of air pressure on objects. E. Torricelli became its inventor. In 1644, the barometer was a tube filled with mercury and a measuring scale. On the day when the barometer was tested, the level of mercury was at around 760 mm, which was the reason to consider the mark at this level as normal pressure. Such devices are still used by meteorological stations.

Two centuries after the invention of the mercury barometer, as a result of many studies, a fundamentally new liquidless type was designed by Lucien Vidi. Subsequently called the aneroid barometer. Throughout the existence of aneroids have gained great popularity among many users, because they are small in size, light and accurate. Compared to mercury barometers, aneroids are completely safe to use.

Types of barometers

Mercury - a device that measures pressure. The principle of operation is the movement of mercury relative to the applied scale.

Liquid - a device with which the level of pressure is measured by balancing the weight of a column of liquid with atmospheric pressure.

Aneroid barometer - the principle of operation and the display of indicators is based on a change in the size of a sealed metal box filled with rarefied air, under the influence of atmospheric pressure on its surface.

Electronic is a modern type of device that converts the linear indicators of a classic aneroid into an electronic signal. The signals processed by the microprocessor are displayed on the liquid crystal screen.

The aneroid barometer is the most common of the above instruments, due to its small size and lack of liquid in the mechanism. Let's consider it in more detail.

The structure of an atmospheric barometer

• Round silver-nickel plate.
• Box with ribbed bases.
• transmission mechanism.
• return spring.
• Pointing arrow.

Atmospheric barometer - principle of operation

When assembled, the aneroid is a box with various mechanisms. When a certain amount of air is pumped out of it, this creates a strong discharge of the return spring, the index arrow and the transmission mechanism between them. Under the action of pressure, the walls of the “pressure chamber” shrink or increase in size, and the pointer begins to move relative to the measuring scale in the direction of increasing or decreasing pressure, respectively. In a calm state, the arrow will be at around 760 mm.

Self-recording barometer

Used to record meteorological data regarding fluctuations in atmospheric pressure. In other words, this is an improved aneroid barometer, with the addition of a clock mechanism to the pressure chamber, an apparatus holding graduated paper and an arrow-drive that puts an ink line on the paper.

The displayed “drawing” on the instrument paper is called a barogram. During the operation of the barograph, in accordance with hourly indicators, the mechanism winds special paper on its base, on the surface of which an attached arrow with ink glides and marks the indicators of atmospheric pressure deviations.

Pressure discrepancies are recorded continuously. For meteorologists, this is the main documented fact of weather changes in the near future. Depending on the size of the drum, the duration of the recording can be from several hours to one week. The special design allows you to take readings and monitor atmospheric indicators at any time.

Barometer in the phone - what is it

Technology does not stand still, and now you can measure atmospheric pressure using a mobile device. Many users of modern gadgets, faced with a new feature, are wondering - a barometer in the phone, what is it? A modern miniature weather station allows the user of the phone to constantly check electronically the level of atmospheric pressure. By tracking the pressure indicators for a certain time, you can find out whether a cyclone or anticyclone is approaching. These indicators will be useful for people with increased sensitivity to sudden changes in pressure.

The capabilities of the mobile device do not stop there. In electronic form, it shows the height, geographical width and longitude, which, in turn, contributes to the rapid search for the device and determining the exact location of its location. Thanks to GPS satellites, the process is fast and accurate. The mobile barometer is an accurate altimeter. The accuracy of determining the location of the user is reduced to a radius of 3 meters. It is these devices that climbers use in the mountains. But they gained great popularity in the aviation industry.

Barometer built into the watch

Appeared relatively recently. Few know what this device is for, and most are wondering - a barometer in a watch, what is it?

Let's try to figure it out. The barometer in certain types of watches is presented in electronic or mechanical form. Electronic view - no different from supplying atmospheric pressure data and displaying them on the screen, like on a phone. The watch with mechanical pressure display is a perfectly accurate mini copy of the aneroid. The only difference is in the simplified scale for displaying readings. The cost of barometer watches is quite high, but, as a rule, they are shockproof and waterproof.

"Non-Standard Barometer"

Thanks to its founders, it is called Harvard. The economic barometer underlies the formation of econometrics. Predicts changes in market conditions, supply and demand dynamics, etc. The Harvard Barometer is a description of empirical patterns and extrapolations over the last months of observation. They are based on a study of the dynamics of development of various indicators of the economy.

The development forecast was displayed graphically. Each curved line plotted on the graph displayed one or another indicator. For example, curve "A" reflected changes in average exchange rates (stock market); curve "B" displayed the wholesale price index and changes in turnover (production); curve "C" - displayed the growth or fall in the price of securities in the money market. In the ideal state of the graph, the indicators "A" and "C" should coincide at the level of the maximum of the first unit and the minimum of the curve of the second unit.

Thanks to the leadership of W. Persons and W. Mitchell, the United States used this kind of device until 1925. The Harvard Mitchell Barometer is the first powerful regulator and indicator of factors in the national economy of the country. Given the popularity and effectiveness of such construction and display of facts, this method has been adopted by many countries around the globe. But the prospect of development of many countries according to this ratio of indicators in the economy did not exist for a long time, because before and after the Second World War - in percentage terms, they became irrelevant. The economies of all the countries that took part in the war were in complete decline, and in order to solve the rise "from their knees", each country applied its own methods to stabilize its own monetary currency. The old methods of raising indicators (getting out of the crisis) were not used at all, but the foundations laid by Mitchell became a precedent for the world economy.

pressure gauge

It is worth noting another device that also measures pressure, but not air, but gases and liquids - this device is called a manometer. These two devices are very interconnected. The sum of the pressure gauge and barometer readings is the absolute pressure, which has a higher indicator than atmospheric pressure.

Conclusion

In the modern world, the barometer is one of the main instruments of meteorology. Marked indicators on paper help many people to learn about upcoming changes in atmospheric pressure, and accordingly, prepare for them. This is especially true for hypertensive patients. A barometer is an optional item in the house, but as an auxiliary element or in addition to the interior, it is desirable. The modern frame of the much-needed device allows it to fit into any interior solution.

Columbus, of course, is not the only brand of weather stations in Russia. Their main difference is an attempt to create an object of interior decoration from a traditionally applied instrument, previously presented in classical forms. A wide range of shades, decoration, the use of brass and aluminum decoration - all this turns an ordinary weather forecasting device into a small masterpiece (a full-fledged interior element).

Why do you need a weather station at all?

Usually we learn the weather from the reports of the Hydrometeorological Center and do not always understand what the final forecast is based on. With the Columbus weather station at our disposal, we can always trust our own eyes to make our own personal weather forecast. This issue is covered more fully in the passport of the Columbus weather stations.

Operating instructions for weather stations, barometers

1. Taking into account the height of the terrain when adjusting the barometer

In meteorological observations, all data on air pressure are correlated with height above sea level. To obtain comparable values, the influence of the height of the terrain on the air pressure is corrected (pressure decreases with height). The room barometer is adjusted so that it indicates air pressure in relation to altitude. Therefore, before use, it is necessary to adjust the barometer to the appropriate height of the place of use. The principle of terrain height adjustment is that the change in air pressure is compensated by correcting the instrument pointer in the opposite direction.
At the factory, the barometer is set to the altitude indicated on the package. Therefore, only in rare cases is it possible to operate the barometer without a new adjustment.
The easiest way to correctly adjust a barometer is to adjust it to a barometer already available in the area or to air pressure data reported in weather reports.
If the height of the place where the barometer is used is already known exactly, then a correction value can be calculated. This calculation is based on the following considerations: air pressure decreases with increasing altitude and dependence: 1 mm of mercury per 10.7 meters of height difference.
Example:
Terrain altitude - 200 meters
Operating height - 40 meters
Height difference - 160 meters
It is required to move the arrow by 160 / 10.7 = 15 mm Hg towards lower pressure to increase air pressure.

2. Adjusting screw

The arrow is moved by turning the adjusting screw. It is made of brass and is located in the hole in the back wall. When adjusting, always take the shortest path.

Since the air pressure in enclosed spaces is the same as outside, the barometer can be hung anywhere. However, it is not recommended to hang it on damp exterior walls or near heat sources. This is especially important for barometers with which thermometers and hygrometers are combined.

Tap the glass lightly before each reading. At the same time, a small friction of the barometer makes it possible to determine the trend in the change in air pressure. It is also possible to make a comparison if, each time after reading, an additional arrow is aligned with the barometer needle.

At an air pressure of 765 mm Hg or more, you can count on calm and dry weather, and the weather is more stable, the higher the air pressure. In summer the weather is mostly cloudless and warm, in winter it is frosty. However, with high humidity and a westerly wind (for the European part of Russia), fog (especially in winter) and rain are possible.
- With a slow and steady increase in barometer readings, an improvement in the weather should be expected, while a slow decline means an improvement in the weather.
-Rapid rise in unsettled weather is often followed by a rapid drop and means continued instability, cloud cover, gusty winds and downpour or hail.
-In winter, an increase in pressure indicates frost, a decrease indicates a softening of frost and thaw.
-Values ​​of 750 mmHg and below are often associated with heavy cloud cover and precipitation. If the air pressure drops well below 750 mm Hg, then strong winds or storms should be expected.
- In summer, a rapid drop in pressure during high heat means a thunderstorm.

6. Temperature and humidity in the living room

A person feels comfort at a temperature in the range of 18-22 degrees and relative humidity in the range of 45-70%. Fluctuations in air humidity in a residential area are mostly insignificant, but in winter the humidity usually drops to 25-40% (especially in rooms with central heating), which is associated with a large difference in the temperature of the room and outside. In this case, the air is very dry, and increased humidity can be achieved with the help of humidifiers.

7. Correction of indications on thermometers and hygrometers

Although the adjustment of dial thermometers and hygrometers is accurately checked at the factory, in some cases, for example: after strong shaking during transport, correction may be required. Corrective adjustment can be made with a screwdriver through the hole on the back cover. In this case, insert a screwdriver into the visible slot on the support of the measuring mechanism. It is recommended to carry out a correction only if reference measurements made with several liquid thermometers or regenerated hair hygrometers or psychrometers show noticeable differences.
The performance of hygrometers and pointer thermometers can be verified by breathing on them from the back. If the capillary thread of the liquid thermometer is broken, it can be reconnected by shaking towards the top of the capillaries or towards the cup. The best way to do this is to use a slow pre-heat that causes the thread to move upwards. In this case, the thermometer must be unscrewed from the frame.

Altitude of the area of ​​application - no more than 300 meters above sea level
- pressure measurement range - from 695 to 805 mm Hg (927-1073 hectopascal)
- temperature measurement range - from minus 10 C to plus 50 C
- humidity measurement range - 0-100%

Instructions for handling weather stations "Columbus"

1. If it is necessary to mark weather stations or stick a price tag, we kindly ask you to adhere to the following rules:
do not stick stickers on the wooden parts of the case of weather stations;
do not use strong adhesives, including adhesive tape;
RECOMMENDED: to identify weather stations, stick a sticker on the back of the product.

2. Pay special attention to the packaging of weather stations. Factory packaging protects weather stations from scratches. We strongly recommend that you package weather stations in the following order:
wrapping;
plastic bag;
bubble wrap.

3. DO NOT use non-wood cleaners. Pay special attention to the varnished parts of the body.

4. Since the weather stations use glass, be extremely careful when unpacking/packing, displaying and moving the weather stations. It is recommended to use special gloves when handling weather stations.

5. When placing weather stations in a showcase, make sure that the weather stations are at the maximum distance from lighting fixtures (especially halogen lamps). The heat emitted by these luminaires can damage the coverage of weather stations.

6. When packing, transporting weather stations with clocks, be careful not to leave batteries in the case. This is due to the risk that the battery may leak.

Careful observance of these conditions will help you provide the buyer with weather stations in perfect condition and avoid possible problems with the appearance and performance of weather stations.

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Barometer - a useful and beautiful gift

What is a barometer and what is it for?

Barometer - a device for measuring atmospheric pressure. When the pressure drops - precipitation is expected, rises - it will be clear. Of course, it is not difficult for a modern person to find out the weather forecast. That's just on different sites predictions can vary significantly. And if on one they advise you to take an umbrella with you all next week, then on the other they will tell you to urgently buy sunblock.

The barometer allows you to make your own forecast, and besides, it is a stylish element of the interior. The barometer looks especially appropriate in the office of a business person.

What are barometers

Barometers, which are used by professional weather forecasters to measure atmospheric pressure, are one thing, and household barometers are quite another. The latter do not require such precision measurements as the former, but, of course, a home barometer can easily predict the approach of a snow storm or the onset of sunny weather. On the other hand, household barometers are compact, beautiful, easy-to-use instruments.

According to the principle of operation, barometers are mercury and liquid-free (aneroids). The mercury barometer was invented by the Italian scientist Torricelli in 1643. By the very name of the device, it is clear that mercury is used for measurement. Under the action of atmospheric pressure, the height of the mercury column placed inside the barometer changes.

The readings of such a device are accurate, it is mercury barometers that are used at meteorological stations, but mercury is dangerous to humans. Rather, mercury vapors are dangerous, which are formed if the device is broken. The same applies to the usual thermometer, familiar to all of us from childhood, but it is still used in everyday life. But as for barometers, the use of mercury devices for domestic purposes was practically abandoned.

Aneroid means liquidless. Such a barometer does not contain any dangerous elements, therefore it is suitable for measuring atmospheric pressure even in a hiking or sea voyage.

Barometer-altimeter Mingle BKT381, designed for hikers, climbers, hunters

By the way, on sale there are also models of barometers designed for hunters, tourists, climbers. However, most often a barometer is an excellent souvenir that is placed on a table or hung on a wall in an office or home office.

Of course, in our age of high technology, barometers are also electronic. In this electronic form, they exist as part of home weather stations, which allow you to fairly accurately predict the weather for the near future, measuring not only atmospheric pressure, but also a number of other quantities by which we judge the weather. And, of course, electronic devices are widely used in navigation.

For example, the Weems & Plath 4002 professional electronic barometer has much more functionality than a conventional analog instrument. Such a barometer records readings for the last 48 hours, and you can set an audible alert for it that the pressure has gone beyond user-selected limits. In addition to pressure, the device measures the temperature and humidity of the air, it also has a built-in alarm clock.

Electronic barometer Weems & Plath 4002

It should be noted that digital barometers, unlike conventional analog ones, are less sensitive to shaking, which is inevitable at sea. Therefore, the owner of a yacht, boat, or other vehicle on water will be much more pleased with a good electronic barometer that can give accurate readings with any pitching than a beautiful, but more capricious analog device, even if made of shiny metal or expensive wood.

At the same time, it is analog barometers, whose appearance reminds us of the era of brave sailors discovering new lands, that are more suitable for the role of a gift. However, some people like classic clocks with arrows, while others prefer to keep track of time using an electronic scoreboard. The same is true of barometers and weather stations.

Vitek Wireless Weather Station/Digital Photo Frame

Electronic appliances fit perfectly into a modern interior, and their functionality is higher. The figure above shows a weather station that is also a photo frame. Such a gift will surely please a person who is oriented towards all the most modern and high-tech.

Atmosphere pressure

So, barometers measure atmospheric pressure. What is it and what is its significance in shaping the weather? The above-mentioned scientist Torricelli once came to the conclusion that air has weight, which means that the atmosphere, consisting of several layers of air, exerts pressure on the Earth. To measure it, he conducted an experiment with mercury placed in an empty vessel.

As a result, normal atmospheric pressure was measured, which at an air temperature of 15 ° C is considered to be a pressure of 760 mm Hg. Art. (millimeters of mercury). In this case, we are talking about optimal readings at the so-called sea level. Whereas high in the mountains, the pressure is lower, because the layer of the atmosphere is smaller there. When climbing mountain peaks, a person may experience altitude sickness, which is associated with difficult lung function at low atmospheric pressure and a decrease in oxygen concentration. Thus, atmospheric pressure is essential to our health.

Home barometers measure pressure in the range of 700-800 mm Hg. Art. at an altitude of not more than 300 m above sea level. These limits are sufficient to display normal changes in atmospheric pressure. In general, in the epicenter of a tornado, the pressure can decrease up to 560 mm Hg. Art. So the approach of the low pressure zone, which is periodically promised to us in television forecasts, means just worse weather conditions, rains and snowfalls. These zones with low pressure are also commonly called cyclones, and those with high pressure are also called anticyclones. Arising in one part of the globe, they are able to travel great distances and, as a result, dictate the weather in a completely different part of it. The approach of cyclones, which bring with them a decrease in atmospheric pressure, negatively affects the well-being of many people, especially those who suffer from cardiovascular diseases.

The barometer helps to predict the deterioration of health and take the necessary medicines in time.

It should also be noted that atmospheric pressure is measured not only in millimeters of mercury. Barometer readings can be given in millibars, which is the unit used by sailors. The normal pressure is 1013 mbar, which corresponds to 760 mm Hg. Art. And in the international SI system, familiar to us from the lessons of physics, it is customary to measure pressure in hectopascals. However, the normal pressure indicator is also 1013 hPa.

In general, if you are not going to cross the Atlantic Ocean alone on a sailing boat, you do not need a thorough knowledge of the features of measuring atmospheric pressure in different conditions. On any barometer in one form or another there are marks "Rain", "Clear", "Cloudy". And when the arrow approaches the sun drawn under the glass, you don't have to worry about getting your shoes wet. And the instructions for the device must necessarily describe how to correct the operation of the barometer if its readings do not correspond to the readings of the local weather station, that is, they are not accurate enough.

Who would be interested in such a gift

In the assortment of a large number of online stores offering goods as a gift for men, there are barometers. Indeed, for a girl, such a souvenir is hardly of interest, but men have always liked various devices. Of course, barometers vary in appearance, but still we are not talking about cute floral designs or glamorous Swarovski stones on the body of the device. Wood and metal are the main materials used in the manufacture of analog barometers.

Barometer PB-14 M made of high quality wood

Barometers are quite consistent with male tastes, fit well into both classic and ultra-modern interior design. They perfectly coexist with the latest gadgets, without which in our time it is difficult to imagine not only the working, but also the home space of a business person. And if the barometer, the case of which is made in the form of a ship's steering wheel, will look better in a room furnished with solid wooden furniture, then the device, placed in a strict metal case of a rectangular shape, can be safely hung on the same wall with an ultra-thin LCD TV.

Metal wall barometer Sea Power

Style

If functionally all analog barometers practically do not differ from each other, then their design may be different. It is the appearance and build quality that you have to focus on when choosing this souvenir. Let's see what the design of barometers are.

antique

The classic round barometer, made in the old Russian style, looks solid, it can be hung both on the wall of the office and at home in the living room.

It has already been mentioned above that there are also such barometers on sale that you can take with you on a hike or hunting, they are compact and easily survive the corresponding operating conditions. Now we will talk about wall-mounted barometers in a wooden or metal case, in the design of which the theme of hunting is used.

Barometer BRIG "Hunter"

Such a souvenir is perfect not only for a fan of shooting ducks, although it is definitely made with such an eye. This gift will fit well into the interior of a country house. It can be hung above the sofa in the living room, where we often find a place for other souvenirs such as an antique blade or a hunting trophy.

Barometer-wheel

Real men know how to overcome difficulties, they do not care about the trials of sea voyages, when huge waves wash over the sides of the ship, and the salty wind beats in the face. The marine theme has always excited the imagination of the boys, and, becoming adults, they continue to see courageous, fearless people in sailors. Therefore, it is not for nothing that manufacturers often attach a steering wheel design to such a device as a barometer, which is directly related to shipping.

Barometer-rudder BRIG

The owner of this barometer can easily feel like a captain of a ship plowing the stormy waters of the Atlantic, and in general such a souvenir looks solid, it is clearly intended for a serious person who is used to being at the helm. It will look great next to the director's chair or next to a large bookcase filled with volumes of classics, as well as in a modern bedroom.

Anchor

Many gifts have not only practical, but also symbolic meaning. The anchor barometer, along with the aforementioned helm, not only exploits the popular marine theme, but is also associated with reliability, stability, and confidence. Such a gift is able to emphasize your attitude towards the man for whom it is intended, as a person who can be counted on in any situation.

Sea Power Anchor Barometer (Brass Case)

Desktop barometers

Some models of barometers are mounted on the wall, while others can simply be placed on the table. Best of all, a desktop barometer will fit into the interior of a personal office; it will easily find its place next to a solid stand for writing utensils. However, such a souvenir will also look good on a student's desk, next to a computer and stacks of textbooks.

Sea Power Desktop Barometer

Defining costs

Basically a barometer is a small object. The diameter of the dial is usually 7-10 cm. Of course, the larger the dial, the more convenient it is to watch the barometer readings, but there is a direct relationship between the size of the device and its price. Naturally, the cost of a barometer is also determined by the prestige of the brand under which it is produced, and the quality of the materials from which it is made. The high measurement accuracy declared by the manufacturer, the low sensitivity of the device to operating conditions and the exclusive design also increase the price of the product.

Barometer "Helm" Sea Power

Let's say this shiny handsome barometer of the English brand Sea Power with a dial with a diameter of 15 cm, made of brass, is sold at a price of about 6 times higher than the barometer of the Russian company BRIG PB-17 Gold with a dial of 12 cm in diameter, made of golden metal. colors. The latter also has a built-in hygrometer (humidity meter) and a thermometer.

Barometer BRIG PB-17 Gold

Some Helpful Tips for Handling Barometers

Barometers cannot be carried on aircraft. Therefore, if you decide to bring a beautiful barometer from a trip to an exotic country, keep in mind that the device is unlikely to survive a flight across the ocean, especially if it travels in the cargo hold with your suitcase. The thing is that at high altitude, the pressure goes beyond the limits in which the barometer measures, and this can damage its mechanism. Sudden changes in altitude, such as when driving downhill quickly, can also adversely affect the performance of the barometer. So try to avoid such overloads of the device.

The instructions for the barometer should indicate the temperature range at which it can operate. Usually we are talking about thermometer readings in the range of -10 ° С ... +50 ° С. And if in our climate one should not expect such heat as in the Sahara, then frosts of -25 ° C are a common thing. Therefore, you should not take the barometer outside when you yourself are forced to wrap yourself tightly in a fur coat. It won't do him any good. It is also not recommended to use the barometer in rooms with high humidity.

conclusions

It often happens that a gift or a souvenir looks beautiful, carries a certain meaning, we like it, and the one for whom it is intended, but does not bring any benefit other than aesthetic. On the one hand, a barometer is a meteorological instrument, its purpose is obvious. On the other hand, it is perfect as a stylish gift that fits easily into almost any interior, looks solid and even expensive. The man to whom you present a barometer will surely like it, because such a gift is not only beautiful, but also an interesting thing that has practical applications. After all, it is always nice to have an accurate weather forecast, while others argue whether it is worth taking an umbrella with you today.