Text 5

I. Read and translate the text paying attention to words below::

Thermocouple

A thermocouple or thermocouple thermometer is a junction between two different metals that produces a voltage related to a temperature difference. Thermocouples are a widely used type of temperature sensor for measurement and control and can also be used to convert heat into electric power. They are inexpensive and interchangeable, are supplied fitted with standard connectors, and can measure a wide range of temperatures. The main limitation is accuracy: system errors of less than one kelvin (K) can be difficult to achieve.

Any junction of dissimilar metals will produce an electric potential related to temperature. Thermocouples for practical measurement of temperature are junctions of specific alloys which have a predictable and repeatable relationship between temperature and voltage. Different alloys are used for different temperature ranges. Properties such as resistance to corrosion may also be important when choosing a type of thermocouple. Where the measurement point is far from the measuring instrument, the intermediate connection can be made by extension wires of the same metals, which are less costly than the materials used to make the sensor. Thermocouples are usually standardized against a reference temperature of 0 degrees Celsius; practical instruments use electronic methods of cold-junction compensation to adjust for varying temperature at the instrument terminals. Electronic instruments can also compensate for the varying characteristics of the thermocouple, and so improve the precision and accuracy of measurements.

Thermocouples are widely used in science and industry; applications include temperature measurement for kilns, gas turbine exhaust, diesel engines, and other industrial processes.

Vocabulary

thermocouple - термопара; термоэлемент;

thermocouple [thermoelectric] thermometer - термоэлектрический термометр;

voltage - вольтаж, электрическое напряжение;

temperature difference - перепад (разность) температур;

temperature sensor - датчик температуры;

to convert - превращать, преобразовывать;

interchangeable - взаимно заменимый, взаимозаменяемый, заменяемый;

accuracy - 1) точность; 2) погрешность;

to achieve - добиваться, достигать;

dissimilar metals - разнородные металлы;

alloy – сплав;

predictable – предсказуемый;

repeatable - с высокой повторяемостью;

reference temperature - эталонная температура; исходная температура;

cold junction - холодный спай термопары;

to adjust - регулировать; настраивать; устанавливать;

precision - 1) точность, прецизионность; 2) сходимость (результатов измерений); 3) разброс, рассеяние (результатов); 4) погрешность

II. Answer the questions to the text:

1. What does thermocouple produce?

2. How are thermocouples used?

3. Thermocouples are widely used in science and industry, aren’t they?

4. Will any junction of dissimilar metals or oils produce an electric potential related to temperature?

5. How are different alloys used?

6. What is the main limitation of thermocouples?

7. What may also be important by choosing a type of thermocouple?

8. Do practical instruments use electronic methods of cold-junction compensation?

III. Translate the following sentences into Russian:

1. A thermocouple or thermocouple thermometer is a junction between two different metals that produces a voltage related to a temperature difference.

2. Thermocouples are a widely used type of temperature sensor for measurement and control and can also be used to convert heat into electric power.

3. They are inexpensive and interchangeable, are supplied fitted with standard connectors, and can measure a wide range of temperatures.

4. The main limitation is accuracy: system errors of less than one kelvin can be difficult to achieve.

5. Any junction of dissimilar metals will produce an electric potential related to temperature.

6. Thermocouples for practical measurement of temperature are junctions of specific alloys which have a predictable and repeatable relationship between temperature and voltage.

7. Different alloys are used for different temperature ranges.

8. Properties such as resistance to corrosion may also be important when choosing a type of thermocouple.

9. Where the measurement point is far from the measuring instrument, the intermediate connection can be made by extension wires of the same metals, which are less costly than the materials used to make the sensor.

10. Thermocouples are usually standardized against a reference temperature of 0 degrees Celsius.

IV. Agree or disagree with the following statements. Give reasons for or against.

1. A thermocouple is a junction between two different subjects.

2. Thermocouples are a widely used type of temperature sensor for measurement and control.

3. Thermocouples are expensive and unchangeable.

4. Any junction of dissimilar metals will produce electric power.

5. Thermocouples are used for measurement of the level of sugar in blood.

6. Different alloys are used for different temperature ranges.

7. Properties such as resistance to corrosion may also be important when choosing a type of thermocouple.

8. Thermocouples are widely used in the beer industry.

9. Electronic instruments can also compensate for the varying characteristics of the thermocouple, and so improve the precision and accuracy of measurements.

10. Thermocouples are usually standardized against a reference temperature of 1000 degrees Celsius.

V. Translate the following sentences into English:

1. Термопары широко используются в науке и промышленности.

2. Применение термопары включает измерение температуры для печей обжига и сушки, газовых выхлопных труб, дизельных машин и других промышленных процессов

3. Электронные приборы могут также компенсировать различные характеристики термопары и таким образом улучшают четкость и точность измерений.

4. Практические приборы используют электронные методы компенсации холодного спая, чтобы регулировать температуру в термопаре.

5. Для различных видов термопар используются разные виды сплавов металлов.

6. Если измеряемая точка далека от измеряемого прибора, то промежуточное соединение выполняется добавлением проводов из того же металла, которые стоят меньше, чем материалы, используемые для создания сенсоров.

7. Различные свойства, такие как сопротивление коррозии также может быть важно при выборе типа термопары.

8. Термопары для практического измерения температуры – это соединение специфичных сплавов, которые имеют предсказуемую и воспроизводимую связь между температурой и напряжением.

9. Любое соединение двух разных металлов производит электрический потенциал, связанный с температурой.

10. Термопары очень точны, очень трудно достигнуть системной ошибки менее чем в один Кельвин.

VI. Insert the missing information into the sentences

1. A thermocouple or thermocouple thermometer is a junction between two different … that produces a … related to a temperature difference.

2. Thermocouples are a widely used type of … sensor for measurement and control and can also be used to … heat into electric power.

3. Different … are used for different temperature ranges.

4. Properties such as … to corrosion may also be important when choosing a type of thermocouple.

5. Electronic instruments can also compensate for the varying characteristics of the thermocouple, and so improve the … of measurements.

6. Thermocouples for practical measurement of temperature are junctions of … which have a … relationship between temperature and voltage.

7. Different alloys are used for different temperature … .

8. Where the measurement point is far from the measuring instrument, the intermediate connection can be made by … of the same metals.

9. Thermocouples are usually standardized against a … of 0 degrees Celsius.

10. The main limitation is …: system errors of less than one kelvin (K) can be difficult to ….

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