Thermometers measure the temperature of gases, including air, liquids, soils, body temperature, objects. They are used to control technological processes in industry, agriculture, in scientific research, in medicine and pharmacology.
The industry produces thermometers of the most different type, purpose, complexity, accuracy and cost. For domestic purposes, you can purchase a reliable, fairly accurate, simple device for very little money. For research purposes, laboratory thermometers are used, which can also be bought inexpensively.
For production or science, highly specialized thermometers are made, designed for certain conditions, operating in a certain range, with a given accuracy. Depending on the scope of application, thermometers can be divided into several groups:
— technical and industrial;
- laboratory;
— meteorological;
- agricultural;
— for oil products;
— vibration-resistant;
- household.
Technical and industrial thermometers are used in pipelines, industrial plants and containers, in refrigerators, in aircraft for continuous monitoring of the state of the environment.
The laboratory thermometer differs in high accuracy of measurements. Such devices are used to measure temperature in various media (for example, liquid thermometer), as well as reference measuring devices. Demanded in biology, analytical chemistry, for measuring very high temperatures. Most models are glass thermometers, they are considered the most practical, they can measure fractions of a degree. Models are available with a ground cone on the body for installation in laboratory glassware.
Meteorological thermometers are used to measure air temperature, the rate of temperature change, minimum and maximum temperatures in a period of time, to determine the temperature of the surface layer of water, deep or surface soil layers. Meteorological thermometers are often included in a set of psychrometers that simultaneously determine air humidity.
Thermometers are also absolutely necessary in agriculture. In particular, you can buy a thermometer for an incubator, for measuring the body of animals, the temperature in a vegetable pile. For example, overheating eggs in an incubator for just a few minutes can cause chicks to die or be born sick, so temperature control is essential. A lot of agricultural processes require strict adherence temperature regime, for example, when storing grain, vegetables and fruits, meat and dairy products, when germinating and dressing seeds.
Thermometers for petroleum products and for testing petroleum products are used 
in the oil refining, oil and chemical industries.
Vibration-resistant thermometers are installed in instruments subject to constant vibration.
Household thermometers are designed for mass use. These include thermometers for liquids (for measuring the temperature of milk, water in a baby bath), and for measuring the air temperature in a room or outside the window, and body temperature.
For precise temperature control working environment you can buy a bimetallic thermometer, the price of which is affordable, and the quality is high - the model "Bimetallic thermometer TB 63" is offered. Of course, in the PrimeChemicalsGroup store you can buy a liquid thermometer, in particular a sp 2p thermometer, a technical thermometer and other models and types of these measuring instruments.
- Mercury
- Standard
- Pediatric
- Electronic thermometers
- Universal thermometers
- oral (nipple)
- Rectal (button)
- ear (infrared)
- Frontal (infrared)
Mercury standard thermometer
A medical thermometer familiar from childhood, consisting of a glass tube with a capillary filled with mercury and a scale from 34 to 42°C. Its advantages are undeniable: it is very cheap, easy to use, does not require any additional care, while the accuracy of its measurement is one tenth of a degree.
Minus - the use of a material hazardous to health - mercury. Being made of glass, it is fragile and, if handled carelessly, can break, spraying many tiny balls of mercury, which are very difficult to collect. If a mercury thermometer breaks, due to the toxicity of its fumes, great care must be taken to collect the spilled mercury. In no case should you collect mercury with your hands or a rag. Spilled mercury should be collected on a copper plate, and the room should be thoroughly ventilated.
It was toxicity that led to the introduction of bans on the use of these thermometers in some countries. Western Europe. The measurement time for mercury thermometers is at least 10 minutes, during which it is very problematic to keep the child in place, and even with a thermometer.
Mercury pediatric thermometer
Essentially the same mercury thermometer. But very light, thin, has a special tip, almost shockproof. Measurement time - 5-7 min.
ATTENTION! A mercury thermometer is suitable for measuring the temperature in the anus and in the armpit, but you can not put it in the child's mouth - the thermometer may break.
Temperature indicator (thermotest)
It is a polymer plate coated with an emulsion of liquid crystals. The thermotest is applied by the indicator to the forehead for 15 seconds. The body temperature is displayed on the indicator: if it is normal, then the letter N is displayed; if it is increased, then the numbers (without tenths) are displayed - 37, 38, 39, 40. It is possible to complete with a simpler thermometer: three scales (N-norm, F-increased and HF-high) or two scales (N-norm and F -increased). Designed for single use. Pros: Such indicators are convenient for monitoring the temperature in young children. The indicator is safe and convenient on the road. Cons: The low accuracy of the indicator allows you to get only approximate data, since the measurement step is one degree without indicating tenths of a degree.
Electronic universal thermometer
Suitable for temperature measurement in any way: orally, rectally, under the arm, in the elbow, in the inguinal fold. Some have special soft and flexible tips for oral and rectal temperature measurements in children. Electronic thermometers measure the temperature not only for children, but also for parents. Equipped with an electric sensor, the readings of which are displayed on a liquid crystal display, the measurement accuracy can reach hundredths of a degree. These thermometers are safe, shock-resistant (some are waterproof) and are able to determine the temperature from 6-10 seconds. up to 3 minutes (depending on model). Expensive models are equipped with a number of additional features- sound alarm (at the end of the measurement, an audible signal sounds), memory (it can store up to several tens of measurement results, thus tracking the temperature curve), timer (the thermometer itself will remind you with a sound signal about the need to measure the temperature after given intervals time), the ability to measure room temperature, automatic shutdown and many other pleasant and useful little things.
For example, the FTE MEDISANA express thermometer has a measurement method selection mode (armpit, oral, rectal). Accordingly, the temperature difference in various parts body. If the measured temperature exceeds the following values, an overtemperature warning tone will be heard.
- Oral measurement > 37.8C
- Armpit measurement > 37.4C
- Rectal measurement > 38C
The tip of the thermometer can be cleaned with any alcohol-containing disinfectant solution.
Frequent errors in temperature measurement such as slipping of the thermometer, insufficient measurement time can be avoided by using an electronic thermometer. It makes it possible to obtain an accurate result from a few seconds to 2-3 minutes, and automatically saves the obtained readings until the next measurement. Cons: doesn't exact numbers when measuring temperature under the arm, as it requires very close contact with the body. Sometimes an error is possible, as a rule, in the direction of overestimation, it is 3-5 tenths of a degree.
Depending on the country of origin and on the set of additional functions, digital thermometers cost from 250 to 1000 rubles.
Children's electronic thermometer
Electronic thermometers, produced specifically for children, have a bright original design(Chicco, "The World of Childhood").
A good gift for a young mother can be a set of baby thermometers from Philips. It is reliable and convenient way measure the child's temperature in any conditions. Includes soft tip digital thermometer, dummy thermometer, extra dummy. In this case, all nipples are sterilized.
Digital oral thermometer (pacifier-thermometer)
Allows you to measure quite easily and simply, because for a child it's just a nipple. Therefore, if your child sucks on a pacifier, then the nipple-thermometer will measure the temperature so that the child will not know that any manipulations have been made with him.
Pacifier thermometer measures the temperature with an accuracy of 0.1 ° C, displays data on the display, gives a musical signal in case of deviations, has an auto-off function. Measurement takes less than 5 minutes. At the same time, it contributes proper development teeth, because orthodontically corresponds to the structure of the baby's mouth. For safety and durability, the thermometer is built into the nipple and is a single piece. Nipples can be either latex or silicone.
The nipple thermometer complies with all consumer product safety regulations and standards, therefore it is completely safe. Suitable for children from birth. Minus - the readings of the nipple-thermometer are not always accurate. If the child cries, breathes through the mouth, the readings will be underestimated. Therefore, if there are signs of fever, and the nipple readings do not satisfy you, you need to measure the temperature with another thermometer. A similar thermometer costs 150-350 rubles. It can only be used if the baby sucks on the pacifier and until and until the batteries are dead. Batteries cannot be replaced. Typically, a teat thermometer provides 2,000 readings - enough to measure temperature twice a day for 2-3 years.
Digital rectal thermometer ("button")
Gives one of the most accurate readings. Designed specifically for children and made in the form of a "button", the "leg" of which is a temperature sensor that records temperature changes in the anus, and the "hat" is a display that displays the measured values. The end of the measurement is accompanied by a sound signal. designed for babies aged 0 to 3 years. Pros: The thermometer "sits" well and is practically not affected environment. The thermometer does not need to be inserted deeply, because the sensor is in the tip. Cons: not every child can be "persuaded" to such a procedure, the rather high price of a thermometer (about 300 rubles), fragility and a "disposable" battery (like a thermometer-pacifier, the batteries are enough for 2000 measurements).
Electronic ear thermometer (infrared)
Today, special electronic thermometers have been developed, the sensor of which is inserted into the external auditory canal. The thermometry of these devices lasts for 1-2 seconds. To do this, you do not need to disturb, undress - the ear infrared thermometer will measure the temperature almost "on the fly".
ATTENTION! In no case should you use the ear canal to measure temperature with conventional thermometers.
The principle of operation of this thermometer is based on the measurement infrared heat emitted by the eardrum and surrounding tissues. To ensure proper accuracy, the thermometer performs a "scan", which takes (depending on the model) 8-16 measurements in just one second and displays the most. The thermometer is shaped to prevent insertion too deep into the ear canal and damaging the eardrum. The ear thermometer comes with an activated Celsius scale. If you wish, you can switch it to Fahrenheit. The thermometer is equipped with a memory mode. The model IRT 3520 of the German company Braun has a backlit liquid crystal display for taking thermometer readings at night. The ThermoTek ear thermometer has an additional feature for detecting the presence of a protective cap. The Tefal 91110 ear thermometer for children has an additional reset button for a replaceable cap, which ensures increased hygiene.
ATTENTION! When measuring temperature with an ear thermometer, the possibility of damage to the eardrum is absolutely excluded, since thermometry is performed in a contactless way (that is, without touching the eardrum) and thanks to special protective caps-nozzles.
Electronic ear thermometer (infrared) - very expensive model thermometer, the price can reach from 1300 to 1800 - 2000 rubles.
Electronic forehead thermometer (infrared)
The new electronic thermometer gives you the ability to measure your temperature with a simple touch to your forehead! It's fast, accurate, comfortable, simple. This is what your child needs. Based on the latest technologies in the infrared region. Measures temperature in a non-contact, safe and hygienic way. Reads forehead temperature value within 1-2 seconds. Gently run the thermometer across your forehead near your temples and almost instantly a beep will alert you that the temperature has been taken. Performs continuously about 16 measurements per second to obtain an accurate value. The ThermoTek forehead thermometer additionally has a decorative stand for easy storage and use for measuring room temperature.
The price of a thermometer is 1300-1800 rubles.
The material was prepared by Ekaterina Belova
A thermometer is a special medical device that allows you to control changes in body temperature, which is necessary for certain diseases. This medical device should be in every home first aid kit. Today there is big choice various thermometers, differing both in the method of measurement, error, and price. What types of thermometers for measuring body temperature are available today and which thermometer to prefer for home use, and which one is more convenient to take with you on trips?
MERCURY THERMOMETER
The mercury thermometer is one of the most popular medical devices, and the most accurate of all. Probably. there are no those who would not be familiar with a mercury thermometer. It can be used to measure almost any temperature - in the armpits, rectal or oral. The measurement error of a mercury thermometer is a maximum of 0.1 degrees and is the smallest of all types of thermometers.
Disadvantages of a mercury thermometer:
- fragility of the product;
- mercury toxicity (if you have to call a special service to exclude mercury vapor poisoning);
- relatively long time measurements - from 5 to 10 minutes, which is a huge minus when measuring temperature in babies, since they simply cannot sit still for so long.
Advantages of a mercury thermometer:
- small error in temperature measurement;
- durability of use;
- universality (they can measure temperature in almost all parts of the body);
- little cost.
DIGITAL THERMOMETER
An electronic thermometer is considered more modern, which is a waterproof plastic case that protects the temperature sensor, which is the main part of the thermometer. With the help of an electronic scoreboard, you can find out the result of the measurement. An electronic thermometer is one of the safest - there is not a glass in it. no mercury. therefore, young mothers prefer to use it.
Disadvantages of an electronic thermometer:
- ease of use and obtaining results;
- short temperature measurement time;
- safety and strength;
- a signal indicating the end of the measurement;
- the presence of a screen with measurement results.
INFRARED THERMOREM
It is the most modern of all thermometers, but, accordingly, the most expensive. The temperature with an infrared thermometer can be read almost instantly, in a maximum of 5 seconds. The principle of operation of the thermometer is as follows: a special element transmits an infrared picture of the body to the screen in the form of numbers. Infrared thermometers can also be non-contact, which is a plus in those situations where you can not disturb the patient.
Disadvantages of infrared thermometers:
- measurement error is at least 0.2 degrees;
- the thermometer must be checked and adjusted;
- only measures certain part body (ears or forehead);
- relatively high cost of the device.
Advantages:
- you can measure the temperature without even touching;
- absence of necessity hygienic treatment device;
- no need to insert a thermometer anywhere;
- ease of use for newborns;
- the presence of a sound signal about the end of the measurement.
THERMOMETER-SOAP
A convenient option for measuring body temperature in babies who cannot sit or lie down in a water position for a long time. Disguise the temperature sensor as a pacifier that is given to the baby. The pacifier itself is made of latex or silicone. The measurement time is from 3 to 5 minutes, but the baby does not feel discomfort. After the measurement is completed, the thermometer beeps and displays the temperature value.
Disadvantages of a pacifier thermometer:
- high measurement error;
- the impossibility of replacing batteries (if they sit down, the thermometer will have to be thrown away);
- the need to suck on the nipple until the temperature is measured.
Advantages:
- ease of measurement in young children;
- disguising a medical device as a familiar object for a baby.
Whatever thermometer you choose for yourself or your baby, it must first of all meet safety requirements, be easy to use and have small percentage errors.
Thermometer translated from Greek means "to measure heat". The history of the invention of the thermometer dates back to 1597, when Galileo created a thermoscope - a ball with a soldered tube - to determine the degree of heating of water. This device did not have a scale, and its readings depended on atmospheric pressure. With the development of science, the thermometer has changed. The liquid thermometer was first mentioned in 1667, and in 1742 the Swedish physicist Celsius created a thermometer with a scale where 0 was the freezing point of water and 100 was the boiling point.
We often use a thermometer to determine the temperature of the air outside or body temperature, but the use of a thermometer is by no means limited to this. To date, there are many ways to measure the temperature of a substance, and modern http://www.sanpometer.ru/termo.html are still being improved. Let us describe the most common types of temperature meters.
liquid thermometer
The principle of operation of this type of thermometer is based on the effect of liquid expansion when heated. Thermometers that use mercury as a liquid are often used in medicine to measure body temperature. Despite the toxicity of mercury, its use allows you to determine the temperature with greater accuracy compared to other liquids, since the expansion of mercury occurs according to a linear law. In meteorology, alcohol thermometers are used. This is primarily due to the fact that mercury thickens at a value of 38 ° C and is not suitable for measuring more than low temperatures. The range of liquid thermometers is on average from 30 ° C to +600 ° C, and the accuracy does not exceed one tenth of a degree.
gas thermometer
Gas thermometers work on the same principle as liquid thermometers, only they use an inert gas as a working medium. This type of thermometer is analogous to a manometer (a device for measuring pressure), the scale of which is graduated in units of temperature. The main advantage of a gas thermometer is the ability to measure temperatures near absolute zero (its range is from 271 °C to +1000 °C). The maximum achievable measurement accuracy is 2*10-3 °C. Obtaining a high accuracy gas thermometer is challenging task, so these thermometers are not used in laboratory measurements, but are used for the primary determination of the temperature of a substance.
Mechanical thermometer
This type of thermometer works by analogy with gas and liquid. The temperature of the substance is determined depending on the expansion of the metal spiral or bimetal strip. The mechanical thermometer is highly reliable and easy to use. As independent devices, such thermometers have not received wide distribution and are currently used mainly as devices for signaling and controlling temperature in automation systems.
Electric thermometer (resistance thermometer)
The operation of an electric thermometer is based on the dependence of the conductor resistance on temperature. The resistance of metals increases linearly with increasing temperature, which is why metals are used to create this type of thermometer. Semiconductors, compared with metals, provide greater measurement accuracy, however, thermometers based on them are practically not produced due to the difficulties associated with grading the scale. The range of resistance thermometers directly depends on the working metal: for example, for copper it ranges from -50 °C to +180 °C, and for platinum - from -200 °C to +750 °C. Electric thermometers are installed as temperature sensors in production, in laboratories, on experimental stands. They are often bundled with other measuring devices.
thermoelectric thermometer
A thermoelectric thermometer is also called a thermocouple. A thermocouple is a contact between two different conductors that measure temperature based on the Seebeck effect, discovered in 1822. This effect consists in the appearance of a potential difference at the contact between two conductors in the presence of a temperature gradient between them. Thus, through the contact with a change in temperature, begins to pass electricity. The advantage of thermocouple thermometers is the ease of execution, a wide range of measurements, the possibility of grounding the junction. However, there are disadvantages: the thermocouple is subject to corrosion and other chemical processes with time. Thermocouples with electrodes made of noble metals and their alloys - platinum, platinum-rhodium, palladium, gold - have maximum accuracy. The upper limit of temperature measurement using a thermocouple is 2500 °C, the lower limit is about -100 °C. The measurement accuracy of the thermocouple sensor can reach 0.01 °C. A thermocouple-based thermometer is indispensable in industrial control and monitoring systems, as well as in measuring the temperature of liquid, solid, granular and porous substances.
Fiber Optic Thermometer
With the development of optical fiber manufacturing technologies, new opportunities for its use have arisen. Fiber-optic sensors are highly sensitive to various changes in external environment. The slightest fluctuation in temperature, pressure or tension of the fiber leads to changes in the propagation of light in it. Fiber optic temperature sensors are often used to ensure industrial safety, for fire alarms, monitoring the tightness of containers with flammable and toxic substances, leak detection, etc. The range of such sensors does not exceed +400 °C, and the maximum accuracy is 0.1 °C .
Infrared thermometer (pyrometer)
Unlike all previous types of thermometers, the pyrometer is a non-contact device. You can read more about pyrometers and their characteristics in a separate article on our website. A technical pyrometer is capable of measuring temperature in the range from 100 °C to 3000 °C, with an accuracy of several degrees. Infrared thermometers are convenient not only in production conditions. Increasingly, they are used to measure body temperature. This is due to many advantages of pyrometers compared to mercury analogs: safety of use, high accuracy, minimum time for temperature measurement.
In conclusion, we note that now it is difficult to imagine life without this universal and irreplaceable device. Simple thermometers can be found in everyday life: they are used to maintain the temperature in the iron, washing machine, refrigerator, ambient temperature measurement. More complex sensors are installed in incubators, greenhouses, drying chambers, and in production.
The choice of a thermometer or temperature sensor depends on the scope of its use, the measurement range, the accuracy of the readings, and the overall dimensions. And the rest - it all depends on your imagination.
The article describes the various types of thermometers used to determine the temperature, focuses on the principle of operation and features.
It also tells about the types of medical devices according to the method of their use, there are characteristics of rectal, ear, head-on devices.
Popular manufacturers and the approximate cost of devices are also indicated.
Thermometers for determining body temperature - what are they
For diagnosis various diseases do not do without thermometers.
Exist different kinds thermometers. Let's list them:
- mercury;
- electronic;
- rectal;
- ear;
- on the forehead;
- infrared.
These types of medical thermometers are used to detect deviations in the temperature of the human body.
High rates may be evidence of various pathologies - this may relate to inflammatory diseases, brain diseases, oncological diseases, etc.
About the principles of operation of various types of thermometers
An electronic thermometer consists of a thermistor, which is the main component of this device.
When the reading fluctuates, it changes the resistance level. To protect the electronic thermometer from damage, its body is made of materials that do not allow moisture to pass through.
After the measurement, a beep can be heard. You can find out the result by looking at the display of the medical device.
Electronic medical thermometer: body temperature is shown on the display. For convenient storage transparent case included
A feature of this model is the presence of interchangeable caps, they are needed for hygienic purposes, they are included.
In order to use the electronic thermometer, you need to press only one button. The result can be seen on the LCD display.
For an accurate result, it is best to use it in the rectum or mouth.
Advantages of electronic thermometers:
- affordable price;
- in a maximum of 3 minutes you can find out the result;
- they are safe in operation - even if the device breaks down, it will not bring harm to human health;
- universality;
- there will be no problems if the device falls into water or on the floor;
- the presence of additional functions in some devices - they can measure the temperature in the room, remind you of the need for what should be measured again;
- you can find completely waterproof models.
Electronic thermometer
There are also disadvantages of such devices. Let's list them:
- if you try to measure with a device under your arm, then most likely it will give inaccurate readings;
- it takes 5 to 10 minutes to measure under the arm, and this is despite the fact that the end of the process signal will sound earlier.
Different types of thermometers allow you to choose any you like, but the most common is mercury.
mercury thermometer
Its peculiarity is that it can remember the last reading. Now this product is the leader in sales.
However, mercury is the sending substance. Fragility - main disadvantage device. then the mercury will come out.
To minimize damage, mercury variants are sold in capsule shells. Even if the thermometer breaks, the mercury will remain inside the capsule.
We list the advantages of mercury thermometers:
- easy to use;
- affordable;
- measure the temperature in different parts of the body.
This type of thermometer has its drawbacks:
- fragile glass;
- mercury is dangerous for human well-being;
- the device may fall and break;
- if it breaks, you can get hurt by the glass.
The principle of operation of a glass thermometer is based on the fact that mercury expands at elevated body temperature: the metal begins to rise along the glass tank.
It is believed that a mercury thermometer is able to give the most reliable readings.
The case is used to store the mercury device. The device should be stored dry, upside down.
The above classification of thermometers includes infrared thermometers. They are also used to determine the temperature of the human body.
Infrared models are most often ear thermometers: you need to insert the sensor into the ear, the results will be displayed on the screen. The end of the procedure will be signaled by a signal, just like in electronic models.
A feature of such thermometers is the presence of a backlight.
Infrared thermometer
The infrared thermometer has its advantages:
- suitable for taking the temperature of a patient who is unconscious or sleeping;
- you can measure the temperature in newborns;
- it is not necessary to apply the device to the body;
- backlit options available;
- for measurement it is necessary to wait only 2 s;
- very convenient to use;
- the device is also suitable for measuring ambient temperature, water;
- additional features include the presence of removable sterile tips and a shockproof housing.
This type of thermometer also has disadvantages:
- high price;
- not suitable for measuring basal temperature.
The operation of such devices is based on the presence of an ultra-sensitive component that reacts to infrared rays emanating from the human body.
All information is displayed on a liquid crystal display. The fact that the device has completed its work can be recognized by the sound signal.
If the device is backlit, then you can see the readings even at night.
Let's talk about. Please read the instructions before using them.
Rectal thermometer
With the help of such devices, you can monitor the state of human health. This device is able to show the temperature measured in the anus.
They are usually used by women. With the help of such thermometers, you can monitor the state of the reproductive function, which will help you find out hormonal background on different days.
Also used to measure body temperature in children - this should be done only when the child is calm.
The thermometer must be inserted into the anus by a maximum of 5 centimeters. It is recommended to use lubricant during the procedure. For this, a baby cream or lubricant is suitable.
They wait a few minutes, then they take out the thermometer and look at the indicators. After use, the tip of the device is treated with an antibacterial wipe.
Using a rectal thermometer
Such thermometers can also be called digital.
Rectal thermometer
We list the advantages of such thermometers:
- after the end of the measurement, a sound signal is heard;
- well suited for children under the age of 3 years;
- the convenience of use;
- since the sensor is located on the tip, it does not need to be inserted too deeply for measurement.
Rectal thermometer
Also, such thermometers have their drawbacks:
- fragility;
- high price.
forehead thermometer
To quickly take the temperature, use thermometers on the forehead. They can be both electronic and in the form of stickers.
Sticker thermometer
For measurement, the forehead must be clean and dry. The thermometer is applied to the middle of the forehead, while the device should be held on both sides. Don't touch the numbers with your fingers.
If you use a sticker, then 20 seconds is enough to find out the temperature. Do not use the sticker thermometer under bright lamps or direct sunlight.
The advantages of such thermometer stickers:
- they can be used many times;
- they measure the temperature as quickly as possible;
- small size;
- no batteries needed for operation;
- the composition does not contain mercury and components harmful to humans;
- especially convenient to use when traveling;
- can be used to measure the temperature of sleeping children;
- with their help, you can monitor whether the temperature drops.
Of the minuses, the following can be noted:
- the sticky layer loses its properties over time, so you have to press the sticker thermometer with your hands to your forehead.
Also can be used. They are also called technical.
liquid thermometer
It consists of a scale, a capillary tube, a liquid, a bypass chamber, a thermometer ball.
The principle of its operation is in the properties of liquids to expand and contract.
When the liquid is heated, it expands, the liquid begins to rise up the capillary tube, which indicates an increase in temperature.
Advantages of liquid thermometers:
- wide application;
- high measurement accuracy;
- ease of use.
They also have their downsides:
- it is impossible to automatically record readings;
- poor visibility of the scale.
A manometric device is used to measure the temperature of gaseous and liquid neutral media.
The principle of the device is based on measuring the pressure of a substance enclosed in a limited space. The readings are affected by the temperature of the sensing element.