Barometer and atmospheric pressure. Barometer - a device for measuring atmospheric pressure
Types of barometers: A mercury barometer consists of a tube filled with mercury and a container of liquid. One end of the tube is sealed, and the other is lowered into the liquid. The aneroid barometer does not use liquid; the sensitive element in it is a corrugated box with slightly rarefied air. This box slightly changes its size depending on atmospheric pressure, these changes are displayed by an arrow attached to it with sensitive springs. Aneroid barometer can often be found in everyday life, beautifully designed it can serve as an unusual gift, not only beautiful, but also useful, especially for a weather-dependent person.
Method of measurement: If you have a home barometer, it is not difficult to measure atmospheric pressure. You just need to look at which division the arrow points to, often on home barometers there are additional designations “clear”, “variably”, “rain”. Moreover, there are barometers with 2 arrows - one of them is movable and indicates pressure, and the second can be moved independently. By setting it in the zone indicated by the movable arrow, after a while you can check the reading of the device and understand whether the pressure rises or falls. It is more difficult to determine the level of atmospheric pressure without a barometer. To do this, you can watch the sparks from the antennas of a tram or trolleybus, with high pressure sparks will be bright blue, and at low slightly greenish. In nature, you can use a branch coniferous tree. To do this, you need to remove all the needles from it except for one, then fix it vertically on the board and observe. In clear weather, the needle will rise, and fall in the rain. However, it is still more convenient to have a ready-made device on hand.
Barometric Pressure Benefits: Needless to say, it helps meteorologists predict the weather. First of all, weather-dependent people need readings of atmospheric pressure. The pressure level begins to change before the weather changes, which means that by observing the pressure variable you can prepare for possible problems with health. People with cardiovascular diseases, hypotension and hypertension, migraines and other diseases react to the weather. Timely intake of the necessary drugs will reduce the risk of exacerbation of the disease during the period of weather change.
The level of atmospheric pressure is not the readings that the announcer lists during the broadcast of the weather forecast on TV or radio. These are indicators that can significantly improve the quality of life for you and your relatives, if you understand them and follow the change in pressure. After all, information about the drop in pressure may prompt you to take an umbrella with you.
Before using the device for the first time, or when moving over long distances, it is necessary to calibrate the device.
Thermometer: measures the current temperature, calibration is not required. Since the device is small in size, it quickly heats up from the heat of the hands, body, sunlight, and the thermometer reading in this case may be higher. To measure the current temperature, you must wait at least 5 minutes for the device's sensor to accept the temperature environment.
Weather forecast: is based on changes in atmospheric pressure, temperature and humidity over the past hours and days (depending on the device model). In some models, it is necessary to set the current weather value from four possible ones: “Sunny”, “Slightly cloudy”, “Total cloudy”, “Rain”. Further, the device accumulates data and predicts the weather. It is recommended to set (correct) the weather forecast on a sunny day. An accurate weather forecast for the next day will be displayed a few days after the device accumulates data.
Barometer: measures relative atmospheric pressure.
Normal atmospheric pressure at 0°C is 760 mm Hg. Art. or 1013 hPa.
750 mmHg Art. equal to 1000 hPa
1 mmHg Art. equals 1.333 hPa.
Atmospheric pressure decreases as altitude or temperature increases.
At a temperature of 0°C and a pressure of 1000 hPa, the baric level is 8 m/hPa. That is, when you rise by 8 meters, the pressure will decrease by 1 hPa.
At a temperature of 0°C and a pressure of 1000 hPa, the vertical pressure gradient is 12.5 hPa. That is, when climbing 100 meters, the pressure will decrease by 12.5 hPa.
With an increase in temperature by 10 degrees, the pressure will decrease by 3.7 hPa.
On average, at low altitudes, every 12 m of ascent reduces atmospheric pressure by 1 mm Hg. Art. At high altitudes, this pattern is violated.
Since atmospheric pressure depends on altitude, then, for example, in the case of the same state of the atmosphere, the atmospheric pressure values in Moscow and St. Petersburg will differ due to the fact that these cities are located at different altitudes. In Moscow, located at an altitude of about 156 m above sea level, the pressure will be about 15 mm. rt. Art. lower than in St. Petersburg, located at an altitude of about 4 m above sea level.
Altimeter: measures barometric altitude. With your position on Earth unchanged, as barometric pressure and temperature change, your altimeter readings can fluctuate up to 20 meters throughout the day.
The altimeter displays relative and absolute altitude. You can reset the relative height level to 0 meters. The absolute height is displayed from sea level. It can be corrected in two ways:
1) By setting the absolute height in the altimeter settings manually;
2) By setting the pressure at sea level in the barometer settings from weather reports, for example, from sites:
http://meteo.paraplan.net/forecast/summary.html?place=3800 (pressure in hPa)
http://rp5.ru/Weather_in_St. Petersburg (pressure in mmHg)
Compass: shows the direction of the north pole. It is necessary to calibrate the compass by rotating it slowly around its axis in calibration mode on a horizontal surface in the absence of strong magnetic fields in order for the compass to determine the north magnetic pole Nm. For the compass to show the direction of the geographic north (true) pole N, you need to set the magnetic declination in the city you need. Magnetic declination is the angle between the geographic and magnetic meridians at a point on the earth's surface. For St. Petersburg, the magnetic declination in 2015-2019 is approximately +11° E. The magnetic declination is constantly changing by fractions of a degree every year.
For any point on Earth, you can determine the current magnetic declination at http://www.ngdc.noaa.gov/geomag-web/#declination
All liquid and digital compasses display the direction of the Earth's magnetic pole, and when working with them, magnetic declination must be taken into account in order to find the direction to the north pole. GPS and digital compasses can show the direction of true north.
Pedometer: measures the number of steps taken, distance traveled and calories burned. In the settings of the pedometer, you need to set the stride length and your weight. The pedometer determines the fact of taking a step by the negative acceleration of the human body at the moment the foot touches the ground, which is recorded by the accelerometer sensor. A pedometer counts steps correctly when it is attached to the correct position in a specific place, usually on the waist belt or wrist. Accuracy is highly dependent on the location of the pedometer and the characteristics of the gait of a particular person.
Periodically check the device settings and adjust them according to the current settings.
A barometer is a device that continuously indicates atmospheric pressure. Its basis is aneroid - sealed container filled with some kind of gas. When atmospheric pressure changes, the geometric dimensions of the aneroid change. This, in turn, causes the arrow to move.
You need to adjust the barometer if its readings differ from the readings of the local weather station by more than 8 millimeters of mercury (mmHg). There is usually an adjustment screw at the back of the case. Turn this screw (but no more than 45 degrees!) until the arrow indicates the correct pressure.
Reference: 1 hPa (hPa, hectopascal) = 0.750062 mm. rt. Art. If both figures are multiplied by 1000, it turns out that 1000 hectopascals are equal to 750 millimeters of mercury.
Electronic pressure transducers are built into telephones. You can read an article about why it is needed in smartphones.
Andrey 18.04.2009 21:44
Bought a Baro barometer. I wanted to take it apart - it turned out that it was not separable. Arrow tight walks — wanted to lubricate.
Rio 21.04.2009 16:57
Nothing, over time, the arrow will work!
Leonid 04/27/2009 09:34
I watched The Cliffs in the store. They were set to hastily. The difference in readings was about 20 mm. rt. pillar. Therefore, after purchase, be sure to check them with a standard or with a radio station.
Victor 04/05/2014 00:07
Hello, Leonid, I also bought a UTES for myself, but I have doubts whether it works correctly or not. You write what you can check with their standard or radio station. Excuse me, Leonid, but how is it done? Sincerely, Victor.
Eugene 28.02.2010 08:10
I bought a Zvezda barometer from the city of Uglich, it showed 760 mm, we had 749 mm - let it down, the next day the pressure increased to 753 mm (it showed an excellent increase), after 2 days the pressure dropped to 743 mm, but on mine it was 753 mm left - is it buggy?
Konstantin 28.02.2010 23:22
Eugene, try tapping the glass lightly with your nails so that the arrow moves. And then the new copies have such a problem that the mechanism is “not run-in”.
puch 17.04.2010 12:04
In fact, earlier in the instructions it was indicated that it was necessary to tap it lightly on the body. I will not go into details of the design, but even AVIATION BAROMETERS tap on glass - there is an INSTRUCTION about this in the description of the device !!!
Vyacheslav 27.11.2012 22:02
Why does my UTES BTK-SN-14 barometer almost always show “Variable” for two months already? The arrow moves to the right, then to the left, but on the markup "Variable" and only once showed "Wind". I have suspicions for the reason that it rained almost every day during these two months, and the arrow never reached the “Rain” marking. Please reply to email. mail: [email protected]
romance 26.03.2010 10:06
Hello. why do you need an arrow fixed on the glass? Thank you.
cook 27.03.2010 18:50
why, to fix values for yourself and see the difference between them 😉
albert 10.04.2012 20:36
see the difference, for example, between the first and second day.
people 18.06.2010 09:51
thanks for the instructions on tapping, I also wanted to take it to the store, although I tapped it. we will wait until it gets used 😉 and who has not bought yet, BUY. you can adjust it yourself: choose the average for several weather information sites. we have a fishing barometer, 5+
Marina 08.07.2010 13:34
I have a German barometer, after it fell into my hands little child, stopped showing anything, who knows if it can be fixed?
Natalya 14.11.2010 13:57
Help, please, we bought a barometer as a gift, while the birthday is far away. We hung it on the wall, decided to check if it works, adjusted it as it was written in the instructions. It has been hanging for 3 days now, and the readings do not change, although there was a sharp pressure drop.
Nikolay 20.11.2010 22:19
Natalya, it is possible that while it has not developed, try to lightly tap on the case with your fingers. At first, mine also behaved this way, and after a while it stirred, now it reacts to 1 mm. rt. Art.
Sergey 28.12.2010 17:20
Tell me, do you need advice on where to hang it correctly: on a sunny wall or in the shade? Or at the window? Thanks in advance.
Gosha 28.12.2010 20:18
Sergey, hang it on the wall, where the sun's rays do not fall.
Victor 27.11.2011 20:12
Remember, great barometer lovers!!! it doesn't matter where you hang it. The main thing is not to lower it into the water, and it is not recommended to knock on it.
Р16 29.01.2017 01:41
you don't know anything about barometers
Alexander 05/07/2014 15:08
I heard that the barometer should be hung on the wall that faces the street (cold), tell me, is this true?
Grisha 07.05.2014 20:50
I don't think it should be exposed to the sun. And on which wall the barometer hangs is not of decisive importance, because the temperature of the walls differs by a degree or two, and the sensitivity of the barometer does not suffer from such a small temperature difference.
Nata 06.11.2011 21:26
And how long did it take for you to move? Mine works only after tapping, but I really want it to work itself.
Goldfinch 07.11.2011 00:20
I started working on my own about a year later. tapped on glass every day before.
Timur 07.12.2010 12:34
But still, you can drop oil on the axis of the arrow !? To make it easier to move! I have a school training BR-52, I knock according to the instructions! There is a difference with the Internet! But, I think, the terrain (mountainous) influences, I live on the third floor, in theory, it should also influence. V Soviet time the quality of the barometers was better, the case was metal, etc., it was more solid!
Pavel 06.02.2011 17:28
The device worked fine. Then, on the back panel, screwed the bolt all the way. How to set it up right now? Thanks in advance.
t_suslova 04/01/2011 07:29
We were given a German barometer, and his school starts at 950. How to set it up correctly if we are 900 m above sea level? In our area, the pressure does not exceed 700 mm. rt. Art.
Alexey 06/05/2011 09:50
950 is not millimeters of mercury, these are hectopascals, 950 hPa is 712 mm Hg. Art.
Max 14.08.2011 16:55
There are two barometers: one is stationary, the second is in gps, in gps there are two parameters in the settings: barometric pressure and atmospheric pressure, what's the difference? The first value is corrected, but the second is not, what is it for?
Lilya 10.09.2011 13:14
How to properly transport a barometer by plane, take it into the cabin with hand luggage? And what will happen to him during the flight? And how do you set it up afterwards? share your experience...
nikolay 26.09.2011 11:50
thanks to all the specialists who wrote that you need to tap on the glass. I bought the device in another country with instructions in English. pressure drops - the arrow stands still until you knock. I thought it was faulty, you can’t return it back, but I just calmed down. while the arrow is lapping, I will tap on the glass.
Gennady 12.10.2011 20:14
Help me to understand! I have two rows of numbers on my barometer. Now, for example, the pressure is 755 mm. I only have numbers from 80 to 102, sort of. How is this to be understood? And then the device is cheap, the instruction is in English. In short, can you throw it away? But he reacts something, but the arrow practically stands still. Help me please. Thanks in advance.
apexander 06.11.2011 16:06
flew by plane for 8 hours. was b-r in hand luggage. unpacked, the arrow is rooted to the spot, at least knock on the glass. behind the adjusting screw twisted, it is possible to scrap.
Alexey 03/29/2012 09:36
The instructions usually read: DO NOT CARRY THE BAROMETER ON AIR TRANSPORT.
Now for repairs.
Sergey 04/02/2012 11:15
Air transport is strictly prohibited. The barometer is not designed for such overloads. The membrane may be deformed or depressurized or the thread may break. After the plane repair is useless. It's easier to buy a new one.
Sergey 29.11.2011 15:56
The main problem with aneroid barometer readings is your geographical position, for example, Astrakhan and Pyatigorsk. Pyatigorsk is located much higher, respectively, less pressure is exerted on the aneroid at maximum atmospheric fluctuations. Therefore, the device will "lie". In this case, you need to change the scale size and adjust. In the case of Astrakhan, the opposite is true. Manufacturers do not indicate the operating height ranges for devices, this is sad, but fixable - you have to refine and adjust.
Xenia 08.02.2012 09:47
Good day! Please help me adjust the barometer, it is 50-60 years old, if not more, what should be done with two arrows so that they show all these pressure drops, etc.? at what value of the numbers should they be combined and what to do next?
Anastasia 14.02.2012 17:57
I bought a barometer, several weeks have passed, and the readings do not change, the arrow does not move a single division. Is he not a worker? Tell me please.
Sergey 03/02/2012 09:34
The same trouble. The pressure dropped by 20 mm. rt. Art., and the arrow is in one place. And another situation: when you try to adjust the arrow goes sharply to the left or right. Is it supposed to be like this or should it move smoothly?
Irina 29.02.2012 19:14
The cat, the brute, dropped the BAMM-1. Shows not. I wonder if it can be adjusted or is it all in the trash?
Andrey 17.03.2012 12:49
I bought myself a fisherman's barometer pb1 on February 23rd. Hung it on the wall. the arrow does not deviate until you knock on the glass. Changed to another, and then another. All instruments have an arrow in place. you need to tap on the glass, but not hard. I won't change anymore. tired. The seller doesn't really explain.
Alexey 03/29/2012 09:32
Yes, that is right. This is a feature of the barometer mechanism, since the indicating (working) arrow is not fixed rigidly, but through suspensions and a mechanism that increases the stroke. At the barometric box, the stroke (compression, decompression) with a change in pressure is very small, not visible to the eye. Therefore, a mechanism was made there that allows, from the smallest movements of the box, to transfer movement to the arrow, which can already walk on a scale of 30-40 cm, and the power of the barometric box itself is not enough to move the arrow a long distance.
Alexey2 16.04.2012 00:09
I hung in the kitchen for three years, everything is ok, recently I noticed that the arrow fell and constantly shows 800. It seems that it just lies and does not move. Took it off, shook it in different sides- the arrow goes to the left, then to the right. If anyone can suggest what to do I would be very grateful. There is no barometer repair in our city.
Olga 18.04.2012 15:22
Tell me, please, I bought "Cliff" with arrows. From the above I understood: you need to knock on the glass, and which one shows the atmospheric pressure, black or the one that moves (gold)? For example, today it is raining, but it shows me that it is variable.
Victor 24.05.2012 22:01
Black indicates pressure.
Alexander 06/21/2012 11:07
Hello! I bought a UTES BTK-CH-14 barometer, I live in Zheleznovodsk (near Pyatigorsk). so, the arrow lies constantly where the rain is, regardless of what the weather is like outside, the pressure changes from 700 to 718 (just the range where the rain is drawn)! Tell me what should I do to make it show the appropriate weather?
Misha 21.06.2012 19:41
What is your pressure according to the weather forecast? If the readings match, then you have to choose - either symbols or numbers.
Alexander 06/23/2012 10:12
to us on Kamchatka only the plane. so what comes out figs to you, and not a working device?
Victor N 01/05/2015 09:06
Put the barometer in the pressure cooker, tighten the lid tightly and seal the vent tube, or into any pressure vessel. About 15-17 years ago, I transported by plane from Kiev to Surgut, and then from Surgut by helicopter to Purpe. The arrow was developed, probably, after the helicopter, you don’t need to tap anymore, he began to lie by 3-4 mm Hg, corrected it with a screw.
Eugene 02.07.2012 22:42
I bought Utes BTK-SN-14, at first I lied at 10 mm Hg. Art., that is, if we have 750, it shows 760, tightened the screw, set it according to the weather station. Reluctance to change, I like the design itself. But the hunt is for it to show accurate data. Otherwise, you will need to sort it out, there is a post where the reason is indicated - the poor quality of the assembly of the mechanism. It is treated with one's own hands, by sorting out the mechanism and setting it up. But it's a shame.
Holy 08.10.2012 11:53
Good day! I bought a barometer "weather harbinger RST04460", the saleswoman said that it needs to be activated (turn the screw at the back 90 degrees), which she did. Are her actions correct? Or take her back?
Holy 27.10.2012 13:33
In short, I took this barometer back and changed it to a German ATF, it seems that all the problems immediately went away, I set the pressure in my region, it shows without problems. BOMB!!!
Alexander 01/27/2017 18:05
Hello! Could you write more precisely what kind of German ATF? I am looking for a German barometer, I live in the countryside, I can only buy it on the Internet.
Michael 03.11.2012 17:02
:bad: Hello. Tell me, did you set up the device according to the weather station of your region, 148 mm normal pressure in our region, and at this pressure it is raining and cloudy. The device should show lower pressure. Please explain.
Lydia 22.01.2013 19:01
How to set up please tell me. TV channels and websites show different pressure. The difference is from 10 to 30 mm. rt. Art.
Alexander 09/18/2013 11:45
First, the barometer itself is inaccurately tuned. Secondly, it does not work well (no stability, low sensitivity, it sticks, it gets stuck when tapped, etc., etc.). As for the difference in readings. Even if you were not too lazy and brought your barometer to the local weather station and there it was adjusted to the same readings as theirs, and then brought your barometer home, for example, to the 10th floor of your “chicken coop”, called back to the same weather station and clarified the pressure readings on the this moment time and found a difference in the readings of your barometer and the weather station, this does not mean at all that the barometer is not working. The rule works here: each increase by 10.5 meters in height gives a fall of 1 mm Hg. (torr) and vice versa. Therefore, if you have a constant difference in readings with a local weather station, for example, 5 mm Hg. and you set up your miracle device there and it works stably, then you can estimate that your refuge-fortress is on the 10th floor with a stable difference compared to the local weather station, for example, 2 mm Hg. is at a height of 2 x 10.5 = 21 meters. relative to the local weather station.
An altitude difference of 21 meters gives a pressure drop of 2 mm Hg. This is a permanent adjustment to your location.
You still do not feel like a celestial? :love:
Alexander 18.02.2013 17:43
I was presented with a barometer BTK-SN-17, I tried to adjust it, the adjustment stroke of 45 degrees is not enough, what should I do? return?
Sergey 03/07/2013 11:40
I see: the children on the ice staged football from some kind of device. Picked up and brought home. BM-2. Made in USSR. The moisture arrow has disappeared. I cleaned everything, read the sites, “sat” and adjusted. Like, shows (reanimated). I have long dreamed of having a barometer.
Konstantin 11.03.2013 00:30
I bought myself a weather station "Kruzenshtern 16" RST05116. Initially, after the purchase, the pressure showed 735 mm Hg. Art. Learned the real pressure in our area. Using the adjusting screw, I set the current 750 mm Hg. Art. For three days the pressure on the barometer has not changed. The arrow stands as if rooted to the spot. Although the pressure in the city has changed (dropped by 8 mm).
What is the problem? Malfunction?
Mikhail 03/18/2013 18:22
I think that the mechanism has not been developed yet. Tap lightly with your fingernail on the glass, the arrow should move. If the pressure has really changed significantly, and the arrow does not move after knocking, then it is necessary to take it under warranty. Good luck to you!
Konstantin 19.03.2013 17:30
Michael, the arrow moves after the knock. And set to the correct pressure. But why doesn't she want to move herself? If this is a mechanism, how long will it take to run in?
Mikhail 03/19/2013 20:52
Konstantin, my BARO device was running in, probably for 2-3 months. All this time I tapped on glass every day. But over time, everything became normal. Now he is 5 years old, he reacts to changes in fractions of a mm. rt. Art. So be patient.
Konstantin 03/20/2013 08:19
Mikhail, noticed that the arrow began to work to increase. I even rejoiced. But when the pressure began to fall, the arrow did not react. I had to knock. Moreover, he knocked not only on the glass, but also on the back of the device. After that, the arrow stood at the set value. Is this the norm? Why is the arrow already moving up, but does not want to go down yet?
Mikhail 03/20/2013 17:29
If she is moving up, then there is already a result! Don't worry, over time everything will work as it should. It's just that the efforts of the membrane and the spring are not yet enough to overcome the friction force of the mechanism. I would not recommend lube. Just wait.
Konstantin 03/20/2013 18:51
Thanks Michael for the advice. I will wait.
Konstantin 03/18/2013 08:30
And in response, silence ... If only someone would advise something.
Victor 06/04/2013 23:09
Tell me, is it possible to transport them in a car (well, for example, to a dacha, to a village or just with a tent to nature) and is it not necessary to constantly adjust them?
Natalya 15.07.2013 09:43
I bought a device for myself, it has a barometer, a thermometer, a hygrometer and a clock, manufactured by Uglich, and all this costs 2050 rubles. I didn’t rejoice for long, because I realized that the barometer was not working (I bought it only because of it), I went to the store a week after the purchase, the seller: “Write a statement”, etc., and I say that I need the device, and not a refund, was then replaced, I came home - it turned out that the clock did not work for this instance (the barometer, as you taught, reacted when tapped), went and changed it to another clock (they are easily rearranged). I honestly followed the new one for another three days - the arrow honestly stands where you put it, if you move it, it stands there, it does not move itself. I told the seller when they changed the watch that next time I would come for the money. But I need a tool. I tapped on him, he lives on his own wave, if he moves, then not in the right direction. Tell me how to be? Maybe you can recommend another one? We don't have many people selling them in our city.
Alexander 17.07.2013 11:41
I read a few comments, my hair stands on end ... The impression is that people are completely unfamiliar with such a concept as atmospheric pressure, not to mention the design and operation of aneroid devices, the relationship of atmospheric pressure with weather changes. Physics Grade 8…
1) An aneroid barometer is a device designed to measure atmospheric pressure. His heart is an aneroid - round, corrugated metal box, from which air is pumped out, that is, a rarefaction is achieved up to values of tens of mm. rt. Art. and less. Under the influence of atmospheric pressure, the box is compressed to an equilibrium state; the elastic force of the box itself and the spring of the transmission mechanism does not allow it to be completely crushed. The box itself is usually made of beryl bronze or similar alloys, which are highly wear resistant and have low CTEC (Temperature Coefficient of Expansion) to minimize reading error with temperature changes. The deformation of the box when the pressure of the atmosphere changes is insignificant, therefore, a transmission mechanism is installed in the barometer, which allows you to increase the value of these deformations and, using the arrow, convert to the value of atmospheric pressure.
With an increase in blood pressure on the box, the effect increases, it compresses more and the arrow shows us by what amount the pressure has increased, with a decrease, under the action of the elastic forces of the box and the spring of the transmission mechanism, it expands and again we determine the magnitude of the change on a scale. Tapping on the device is necessary to eliminate the effect on the readings of the friction force in the transmission mechanism - it is a system of levers on the axles, and friction forces arise in them. But, as a rule, with a serviceable and properly adjusted device, this manipulation does not cause changes in the readings by more than 1-2 mm. rt. Art. The range for measuring blood pressure with household barometers is small, from 700 to 800 mm. rt. Art. and less. When flying by air, the pressure in the cabin reaches values of 600 mm. rt. Art. and below, during transportation of such a barometer, it may break. As a rule, the delicate transmission mechanism is damaged. The aneroid box may also become unnecessarily deformed, which will affect the accuracy of the readings in the future. The same thing can happen with a barometer and when exposed to pressures above 800 mm. rt. Art.
2) The relationship of weather changes with changes in blood pressure was established by E. Torricelli, the creator of the mercury barometer. When the pressure decreased, the weather "spoiled"; when the pressure increased, it "improved". When forecasting the weather, it is not the value of pressure itself that is more important, but its changes! For this, there is a second arrow on the glass of the barometer, which we combine with the arrow that displays the level of blood pressure. When the pressure changes, we can judge the trend in the development of events. And it does not matter at all whether we live in Astrakhan or in Pyatigorsk. It is not necessary to directly correlate with the inscriptions on the barometer (clear-variable-storm, etc.) with the state of the weather. I repeat, CHANGE HELL is IMPORTANT. Let's say there is a wonderful clear weather outside the window. AD = 730 mm. rt. Art. Then, after lunch, the arrow crept down - we should expect worse weather. The degree of deterioration depends on the magnitude of the change in blood pressure. And vice versa.
I hope my post will be useful for someone when choosing a borometer and using it.
Eugene 08/27/2013 09:08
Comrades, please help!
I found a completely disassembled barometer at home, the arrow separately, the mechanism separately, the metric scale (disk) separately. How to assemble this device so that it works?
Alexander 04.09.2013 15:38
I recently won 2 lots - barometers (various, including marine ones, but in the style of "a la grandfather's barometer", which I didn’t take, I don’t like it) at the German eBay online auction. I had to look for happiness there, because modern clumsy antique fakes like RST or Utes and etc., which are now sold in Russia, are not inspiring to buy. Yes, and the price for them is ceiling and inadequate. This is so, by the way. These two barometers were sent to me in Belarus from Frankfurt am Main as an ordinary air parcel by plane. The flight went well. Both workers. :ups: So, for some reason, the air shipment had no effect on German barometers, although at first, to tell the truth, there were fears. A lot of barometers are sold on eBay all over the world and the shipment of purchases (lots won) also goes to different parts of the world and usually it is by air, and I have not met such questions. Maybe this applies only to Soviet barometers? Or is it a myth?
By the way, about setting the barometer. The barometer reading is affected by your location above sea level, i.e. every 10.5 meters of altitude gives a pressure drop of 1 mm. rt. st (in English it is denoted by torr). Therefore, in order to fine-tune your barometer (which is already working well, that is, sensitive and does not need to be forcibly pushed by tapping), we take our feet in our hands and a thin screwdriver under your adjusting screw on back wall your barometer and direct our feet to the local weather station. There we ask for permission and favor and put on your barometer, which you brought with you, the same readings as on the exemplary one from the weather station. We make a temperature correction if it is provided for in the weather station barometer (i.e. if there is not a temperature-compensated barometer there, but you rattled there, for example, your marine barometer from the Japanese company YANAGI TYPE 8 COMPENSATED TEMPERATURE & ACCELERATION, which you won on eBay and cost you taking into account transportation from the States at $ 200 and local meteorologists, the toad will begin to choke).
After that, you have a barometer that is identical in readings to the exemplary one from the weather station.
Alex 02.10.2013 15:22
P.S. And after you brought the barometer home and called back to the weather station and found a difference in readings with them, this means that you and the weather station are on different height relative to sea level. This is, as mentioned above, the correlation (constant correction) to your location due to the difference in heights.
Irina 13.09.2013 01:41
Barometer "Utes" BTK CH8 large has been showing 750 mm for 2 days without any changes. We've had rain all these days. I just got it, I haven't seen any other indicators yet...
Alexander 09/18/2013 10:52
P.S. With thermal compensation and the influence of your location (altitude relative to sea level), it seems to have chewed it up as popularly as possible.
Now about the "development-running in" of the barometer. So that there are no questions during the operation of the barometer, I propose a very simple way to check it right at the place of purchase and bring it into working condition (reincarnation or "revival") and increase the sensitivity (reduce the effect of tapping). The operation is something akin to checking the place of a thermos - pouring into it hot water, wait a few minutes and check the case temperature. If it is slightly warm only in the cork area, then it is whole and there is a vacuum. Were distracted.
So, we take a durable plastic transparent bag (preferably a few in reserve if they burst) larger in size than the barometer itself. We put a barometer in the bag, put it on a flat stable surface such as a table, inflate the bag with our mouth (like a balloon), tightly close the bag outlet. We make sure that there are no air leaks from the package. Click on the package. The barometer needle deviates in the direction of increase, up to about 20 mm Hg. (no more effort needed). If the arrow deviates and returns to the same position when the pressure on the package is removed, then your barometer is working.
We carry out the same operation, only repeatedly to “bring to life” your “fallen into a coma, or maybe not out of it” barometer. True, this can only help if the vacuum box in it is tight (there is a vacuum) and there are no other mechanical damages along the vacuum box - arrow chain.
And you don’t have to wait for six months or a year and knock on it, otherwise during this period you will turn into a woodpecker. To do this, it is only necessary for some time to make certain efforts to compress the inflated package. Physical exercise in moderation will not hurt anyone, the main thing is not to overdo it.
By the way, I recently purchased a Soviet marine barometer manufactured in 1957, manufactured in accordance with GOST 6466-53 (now this GOST is not valid). Awesome thing. On eBay barometers of this type are usually sold in a round case under the brand name "Stalin era" or "period Cold War". Many modern Shirpotrebovsky lurid single-chamber barometers are not suitable for him and soles. Triple vacuum chamber (for increased force), scale graduated at 0.5 mmHg, black rectangular Bakelite body. No stupid inscriptions like "Dry, Storm, Fair, Rain, Pogodnik and etc." There was no response to knocking on it. Works great. Once transported in a bus, the trip was made through a very hilly area. It was interesting to watch him independent work. As soon as the bus entered the lowlands, the pressure increased. As soon as the bus entered the hill, the pressure dropped right before our eyes. Those. the rule worked - each increase by 10.5 meters in height gives a fall of 1 mm Hg. (torr) and vice versa.
Alexandra 06/28/2014 12:32
Thanks a lot. Your information is very valuable. I bought a BARO barometer, now I know that it is “alive”, the trick with the package was a success. :love:
Roman 18.03.2015 22:29
Experience with the work package. And how to check the arrow in the other direction?
Igor 03/20/2015 23:47
Inflate the bag and burst it.
Alexander 06/26/2015 09:48
In this case, on the contrary, you need to create a small vacuum in the bag if you can 😎
Although why is this, if it reacts to excessive pressure, then it is working
Sergey 14.11.2013 05:09
I understand that transportation by air is prohibited, but if the aircraft does not rise above 7 km, does this rule apply to it? I simply don't have any other transportation option.
Vasily 01/25/2014 07:21
I live in the countryside and there are no weather stations nearby. How to adjust the barometer in such cases?
Yup 25.01.2014 14:41
Internet weather forecast for your countryside.
Alex 30.01.2014 17:24
Try to get out of your countryside and drive up to the local weather station. This is if the terrain is hilly. If in no way, and the terrain is flat, and the difference in heights, in theory, should not affect the readings, then it’s better to still get through to the local weather station and clarify the readings with them. Usually there are weather stations in all regional centers.
Viktor 04.03.2014 18:20
my barometer shows 770 mm, and the Internet shows 750. what should I do?
CAT 13.06.2014 20:35
Tell me where the pressure is higher: on the first floor or on the tenth?
Galina 04.07.2014 13:51
Please help... They gave me a BRIGANT meteorological corner with a barometer, a hygrometer, a thermometer, and a clock. I adjusted the black arrow with a screw, focusing on the weather data. But the barometer readings have been the same for a week now. It's a shame. What to do?
Alexander 08/20/2014 06:39
Galina 2014-07-04 13:51:18
In such "instruments" there is no need to hope for any accuracy and repeatability of the measurement.
The friction force in the transmission mechanism is such that the arrow may not budge even when the pressure changes within + - 10 mm Hg.
If you need a device that measures atmospheric pressure, and not just a display meter, then I recommend the following models: BAMM-1 (+ - 1.5 mm Hg). M-67 (Control - + - 0.8 mm Hg), M-110 and the like. The error is indicated, of course, for the entire measurement range of the device, that is, from 600 mm Hg to 800 and, as a rule, in the measurement range of 710-790, no correction is introduced at all, only temperature (for many devices that I verified, it is 0 ).
One user wrote about flights from Germany and everything is OK - I do not agree with you. In order to declare this, it is necessary to check in a thermal pressure chamber, in the entire operating range.
Antoha 20.08.2014 18:28
Good day to all! I'll tell you about mine. About 3 years ago I bought a barometer BK-S, made in 1978, excellent condition. Showed about 753, hung like that for two months, maybe it changed, but very slightly. One day an acquaintance came and drew attention to him, we started talking and I told the whole story, to which he suggested that I set up and check the device. I set it up and checked it in a metrological laboratory, they “chased” it for about a week in some kind of pressure chamber, I don’t know for sure, in general, he brought it to me, said that the barometer was a thing, it showed clearly, it reacted very quickly. When I returned it, it showed 746, then I looked in the net - it’s the same + - 1-2 units. I hung it up and forgot it, but when I look, the maximum units change by 10-12 at any time of the year. Even when it's raining, my needle "hangs" above 740 on a scale between "wind" and "variable", although "rain" on it is 720-730. I looked at the same Yandex weather, everything is the same, the pressure is 742. Therefore, I think it depends on the terrain and relief, or maybe something in nature has changed !!! I live in Stary Oskol, Belgorod region.
Alexander 08/28/2014 06:17
As it has already been written here repeatedly, weather changes and the inscriptions on the barometer itself are in no way connected with each other! It is not the value of atmospheric pressure that is important, but the tendency of its change! In mountainous areas, normal pressure may never rise above 700 mm Hg at all, so do you think there are continuous rains and hurricanes there?
Ilyas 17.04.2017 23:09
Tell me please. They gave me a barometer in Rostov-on-Don (it worked as it should), after I brought it home to Pyatigorsk by car, it stopped working, hangs, is silent. Transportation in soft packaging - shock excluded, in a horizontal position. How to revive and make it work?
NICHOLAS 29.01.2015 19:57
Dear friends! You don't need to configure anything.
At the factory, they (barometers) are adjusted according to the standard. And since each locality has its own height in relation to the sea, the readings will be different.
This applies specifically to the factory.
As for others, I will not say anything.
But after your "settings" there will be "glitches".
Example. In Moscow (center) 739 mm Hg. Art., in Lyubertsy 750.
It's raining in Moscow, And in Lyubertsy there is no cloud, no wind, in this example there is a big gap, but it's true.
Once we went fishing, the weather is calm, the morning is just “class”. after driving 15-17 km, the weather deteriorated sharply, after spending 2-3 hours in the pouring rain, they returned with nothing, while returning back, the weather was the same - calm, not a cloud, the sun, peace and grace. After asking about the weather, they were very surprised - nothing had changed, and there on the horizon (looking from the roof of the house) there was a black streak of bad weather.
Draw your own conclusions. and you can climb the barometer mechanisms.
Thanks, good luck!
Olga 14.09.2015 15:40
I checked the barometer with a package, everything works. Thanks for the advice.
Zinaida 09/15/2015 13:19
Alexander, your comments are very useful, but I can't set up my BARO hPa barometer, because the numbers on it are from 980 to 1040, and the pressure in our city of Novosibirsk is 740-760. Even if the weather station says exactly mm. rt. Art., what's next. And I still can’t figure out how to put, or rather, which arrow the right numbers. I have two arrows on it, black and gold, black moves up and down, and gold stays in place. Tell me please. I got it without instructions. Many thanks!
Roman 15.09.2017 10:34
1 hPa = 0.750062 mm. rt. Art.
hPa (in Russian hPa) - hecto-pascal - a unit of pressure.
Accordingly, 750 mm Hg. equals 999.9 hPa.
Alexander 10/19/2015 15:47
They presented the St. Petersburg Brig, I can’t adjust it to the reduced pressure at sea level. There is not enough adjustment travel in + and the arrow scratches on the dial. Shows actual pressure. We have 480 meters above the Baltic. The weather station from the same company is perfectly regulated. You don't even need to click. I set everything up according to the airport data, because I am at the height of their weather station.
How to disassemble and rearrange the arrow?
Nikita 03.12.2015 01:17
I bought a barometer, they said Russian, but there was no manufacturer in the instructions, and on the Internet the exact same weather station is indicated as a Chinese one. I observe. The arrow deviates, does not freeze, i.e. seems to work; the difference with the district center is plus one in its (district center) favor (I check it on an Internet). But the question is: the yellow arrow in my model does not move (the black one can be adjusted with a screwdriver, which is attached), the yellow one froze at 748 mm. rt. Art. ? This is fine? At the father's house "Cliff" (with a yellow dial and a bunch of inscriptions), it has been working well for a couple of years. He also looks only at the deviation of the arrow when he goes to fish. But his yellow arrow rotates freely.
PS. I've read all the advice, thanks. There is a lot of useful information on how to use this device. Now, according to the local advice, I look at the deviation of the black arrow down or up from the yellow one, and so I try to determine the weather.
Nikita 08.12.2015 20:22
By the way, if anyone has a BAMM-1 barometer, tell me how to set it up so as not to break it (I got it on occasion, but I don’t know yet if it’s working), and in what case should it be set up at all?
Gerhard Schroeder 25.11.2016 13:31
I do it very simply: I adjust according to the built-in barometer of the casio watch. If you don't have a watch, your phone may be able to measure blood pressure.
Alexander 11/30/2016 19:48
About air travel. Traveled from Moscow to Vladivostok by plane. At an altitude of 10,000 km, it showed complete discharge, i.e. the arrow was in the extreme left position. As soon as the descent began and the arrow crept, it was very interesting to watch, especially when descending from 1 km to 500 meters. The arrow was ready to jump out. Brought home, hung on the wall, two days later he healed his ordinary life and shows all changes. therefore, he is not afraid of flights, it all depends on the quality. Mine is still old from the USSR, maybe that's why it still works.
Yuri 01/30/2017 07:52
I bought a barometer on Ali for 20 bucks. Dial diameter 12.8 cm. Delivered by plane through Finland. Shows normally, but without tapping does not want to. I have been watching for two days, now it showed 756 mm. rt. Art., tapped, began to show 754.5, I think it will develop over time. It also has a thermometer and a hygrometer.
Natalya 15.09.2017 05:49
The old German barometer was transported by plane in luggage, she was afraid that antiques would not be allowed to go abroad. There was no other transportation option besides the plane. As a result, the barometer does not work. I live in Latvia. What can be done, where and how to repair? Is it possible to replace the damaged part?
Vlad 09/15/2017 10:27
Natalya, why did you decide that it does not work? The arrow does not move or is littered over the edge of the scale? Maybe the pressure in your area is not changing noticeably.
If it is really broken, I think there is an option to show the watchmaker. If a gear jumped there, a rod or a spring broke, the watchmaker will be able to repair the device. Good luck! Report the result here.
Vladimir 08.10.2017 19:10
Very tight arrow, moves only from strong tapping. Maybe disassemble and lubricate the mechanism? Soviet device, Cliff. Will lubrication damage the part? What oil to use? Machine or silicone? Thanks for the replies, who had a similar experience.
A modern person from childhood gets access to complex and functional electronic devices. Such accessibility of technology has led to the fact that classical devices almost do not arouse interest and gather dust on the shelves in complete oblivion. All these compasses, thermometers and barometers, with the help of which our grandfathers and even parents used to navigate the world and assess the state of the environment, seem to be outdated and boring toys. And in vain. It is precisely about the barometer that I would like to talk in more detail. Because, despite the obvious and rapid technological progress, this device remains indispensable assistant to determine atmospheric pressure. And it equally influenced and influences both us and our ancestors. And even today, when everyone can have a portable weather station in their pocket, its operation is still based on the principle of that same barometer.
Of course, now barometers differ from their ancient prototypes - both externally, and constructively, and functionally. But the essence of their action has remained the same, and it is indispensable for every person who does not live in complete isolation from the world around and breathes the air. Atmospheric pressure affects everyone and everything. And, if we usually notice the weather and its phenomena, such as the sun, rain, wind, then it is worth considering that all these manifestations can be predicted in advance by measuring atmospheric pressure with a barometer. Such measurements help to prepare in advance for the upcoming changes in weather dependent people and those who just go on a long trip and want to know what the weather will accompany him on the way. To do this, you can simply watch the forecast on TV or on the Internet, but it is much more reliable to control what is happening yourself. And for this it does not hurt to learn how to use a barometer.
The structure and functions of the barometer
A barometer is a device that measures the pressure of the atmosphere and displays the results of these measurements in human-understandable terms. But he does not have artificial intelligence and has no direct connection with space satellites. So how does he do it? Yes, very simple. The simplest barometer was based on the ability of a liquid to move under air pressure. The first liquid used for this purpose was mercury, enclosed in a thin vertically oriented glass tube. Back in 1643, the author of this design, Evangelista Torricelli, thought of lowering a hollow tube sealed from the upper end into a vessel with mercury and observing how the “mercury column” rises or falls under pressure.
Rumor has it that Galileo himself inspired him for that ingenious invention at that time. But be that as it may, the mercury barometer was a rather dangerous device, and therefore, almost from the moment of its creation, the search for other options that did not involve the use of toxic liquids began. It was possible to find a satisfactory method only by the middle of the 19th century, when Torricelli's compatriot Lucien Vidi showed the world the mercury-free and generally liquid-free barometer he invented, which was naturally dubbed an aneroid (in Latin - "without liquid"). The aneroid barometer immediately fell in love with the sailors, because it could withstand the ship's rolling and shaking, and they use similar devices to this day. In fact, there is nothing complicated in them either: just a metal box with thin walls, inside of which there is a vacuum or very rarefied air. The air pressure bends the metal, which in turn pulls the attached spring. An arrow is attached to the spring, indicating the divisions of the scale.
The main advantage of this design is safety and accessibility. The main disadvantage is a small, compared with a mercury column, accuracy. Therefore, funny as it may seem, the readings of aneroids are sometimes rechecked using liquid barometers. For travelers and yachting enthusiasts, accurate readings are very important. Oddly enough, many of them still use classic aneroids - either there is a certain charm in this, or conservativeness affects. Although today the problem of measurement error has practically disappeared, and traditional models of barometers play the role of rather status souvenirs and stylish decor than measuring instruments.
If you need to know the atmospheric pressure, it is much easier to use a compact electronic barometer. In it, metal plates are successfully replaced by microscopic capacitors and circuits, sometimes by crystals. Such a digital device is easily integrated into Wrist Watch and / or a radio receiver, does not take up much space and does not fail in the data provided. Moreover, even barometers built into mobile phones, and special applications for smartphones, not only measuring pressure, but also associated with GPS-navigators. In other words, there is nothing easier than to find out the current and future state of the atmosphere, the weather for tomorrow at different points the globe. But, if not for the first barometers, invented almost half a millennium ago, one could only dream of this newfangled comfort.
Rules for using the barometer
So, there are several types of instruments for measuring atmospheric pressure, each of which is, in fact, a barometer, and at the same time has its own characteristics, advantages and disadvantages. But, if you still decide not to limit yourself to ultra-modern devices and master the use of a classic barometer, then there are good reasons for that. In some cases, this may be a desire to understand the structure of traditional technology, the desire to classic style in the interior and everyday life, or just curiosity. It happens that a desktop barometer is given as an expensive souvenir, and it's a pity not to use a new beautiful thing. Either way, here are some tips for using a barometer at home:
- mercury barometer will display atmospheric pressure in millimeters of mercury. Mercury (perhaps another, safer, colored liquid) is inside the flask, which is marked with divisions. The value of each division depends on the size of each particular barometer, check it to avoid errors. Then just look at how high the bar inside the flask has risen and what number it points to. Please note that the barometer must be strictly at the level of your eyes, otherwise the readings will be distorted. Try not to move the device or touch it at all with your hands, because its sensitivity is very high, and the data may go astray.
The mercury barometer is the simplest device, and it only shows the state of the atmosphere directly around it, in the room where it is placed. Therefore, it can be problematic to assess the pressure outside the window or even in the next room with it. To do this, you will have to move the barometer to a new place and wait until it adapts to new conditions. However, just such a barometer for a long time was the most common device for measuring pressure, and mastering it is no more difficult than learning how to use a household thermometer. Today, more modern and functional barometers are used in most homes and offices, but a mercury model can still be found and bought at a pharmacy or hardware store if needed.
- Aneroid box. It can be placed on a table, hung from the wall in the bedroom (this can still be found in the homes of the elderly, whose well-being depends on atmospheric changes) or attached to window glass. The size of this device can be different, from a very miniature round to an impressive “washer” in diameter. But outwardly, it always represents a dial with a movable arrow above it. On the dial, in addition to numerical designations, words can be written, such as: “Clear”, “Dry”, “Variable”, “Rain”, “Storm”, etc. As you might guess, these tips serve to make the barometer even easier to use.
By by and large, you just need to look at which word the barometer needle is currently pointing to. Everything technical subtleties will remain outside your attention and should not worry you, because the necessary information in a simple and understandable form is already in front of your eyes. For your part, you can participate in the compilation of short-term forecasts and observations of changes in the atmosphere, if the design of your barometer suggests the presence of not one, but two arrows. You can turn the additional hand in the same way as you set a mechanical alarm clock. If you compare it with the second arrow, then after a while you will be able to notice whether there have been changes relative to this position - that is, whether the pressure has changed, and, if so, in which direction.
- Electronic barometer even easier to use than the classic aneroid. Most often, it is called a weather station for the possibility of combining several functions at once and sufficiently detailed monitoring of weather changes and forecasts. The only difficulty you may have when reading the readings is the confusion among the many numbers and icons displayed on the digital barometer display. Indeed, in pursuit of external showiness and design frills, many electronics manufacturers forget that any device should first of all be convenient in practice. This is the main task of the ergonomics of the case and the screen of the barometer, and not at all in its futuristic and amazing design.
An electronic barometer usually has a housing and a flexible sensor designed to be placed outside a window. The sensitive end of the sensor captures any changes in humidity, pressure, strength and direction of the wind on the street, and the screen on the case immediately (or with a minimum time delay) shows you information about this. Even in the simplest digital models of barometers, you can see the current time, air temperature (outdoors and / or indoors), air humidity and, of course, atmospheric pressure. The latter is traditionally conveyed in conventional "millimeters of mercury". And although there is no mercury column inside the barometer, these units of measurement are considered generally accepted when we are talking about measuring pressure. Most likely, your electronic barometer is not limited to digital indicators and at the same time diversifies the data with icon pictures depicting the sun, clouds or rain.
And finally, it remains to decide what type of barometer to choose for personal use. There can be no hard and fast recommendations here, and you are free to focus on your own taste, fashion trends, the style of the interior or simply the prevailing circumstances. The main thing is that it is convenient for you to use it, and information about atmospheric pressure and other weather parameters is visual, understandable and easy to understand. After all, the primary function of the barometer is precisely this: to promptly and accurately inform you about the state of the environment. Focusing on it, you will be able to plan your day in advance, which is especially important for representatives of mobile professions, enthusiastic hunters, fishermen and tourists. For them, the barometer is simply indispensable, and therefore it will become great gift for any holiday or just for no reason, as a sign of respect for their activities.
often require adjustment. This must be done so that the error of the device does not interfere with correctly predicting future weather. If the barometer is strongly confused, then the movements of its arrows will incorrectly display a drop or increase in pressure.Many people adjust and calibrate barometers themselves. The online store offers to buy mechanical aneroids, which are easy to study and fix yourself if necessary. In order to properly set up home barometers follow our advice below.
How to understand that the barometer needs to be adjusted?
Check your instrument readings. Track: compare its data with those broadcast on radio, television, or with a summary of the hydrometeorological center. For comparison, take the information that is given specifically for your region. It is impossible to compare the readings of a home barometer with data for a neighboring area: at a distance of several kilometers, these figures can vary significantly.
The normal error can be up to 8mm. rt. Art. If your barometer does not exceed the allowed error value, then you do not need to adjust it. If the device shows data with exactly this or greater error, then it needs to be calibrated. It is not difficult to do this, after reading this article it will become absolutely clear how to properly configure barometers. Online store presents mechanical models that are easy to understand, you just have to follow our step-by-step tips.
How to set up a barometer?
· Find the thin black arrow. It is called index and we need it in order to correctly set the sea level at which the device is located.
· There is a large adjustment screw on the back of the barometer. Take the regular wrench, and use it to turn the adjusting screw so that the black pointer indicates the sea level that is correct for your city.
· Once again check the correct position of the arrow.
· Check the barometric pressure data that is correct for your location. Use the news bulletin or weather forecast.
· Use the barometer's center knob to turn the second hand so that it accurately indicates this data.
· Hang the barometer on a wall or place it on a table. Make sure it works properly by tilting the entire body of the instrument about 45 degrees. If the thin black pointer turns clockwise, then everything is in order with your barometer: this is the normal reaction of the device to a change in position. But if the arrow does not make a turn - contact a specialist. There may be trouble or a malfunction with the device.
When checking your home barometer, remember to check for accurate reports. In addition, it is desirable that the device be at the same height above sea level as you are - otherwise the weather forecast made using such a device will not make any sense. Also pay attention to the correct installation or mounting of the barometer: only the correct location of the device will make its readings accurate. But, on the other hand, remember: there is no difference whether the device will stand in an apartment or house, or be on the street. At correct installation, the barometer will show changes in atmospheric pressure correctly.
Most barometers do not require frequent calibration or adjustment. This is a durable device that is designed for many years of operation. Before taking any action, check carefully whether there really is an error in his testimony.
