A thermometer is the highest thermometer that records the highest temperature that the thermometer has measured. So, what do you know about the type of thermometer? Here's a list of things for everyone, let's take a look! The types of thermometers are as follows: 1, gas thermometer: use hydrogen or helium as the temperature measurement material, because hydrogen and helium liquefaction temperature is very low, close to absolute zero, so its temperature range is very wide. This kind of thermometer is very accurate and used for precision measurements. 2, resistance thermometer: Divided into metal resistance thermometer and semiconductor resistance thermometer, are based on the characteristics of resistance changes with temperature made of this feature. Metal thermometers are mainly used for platinum, gold, copper, nickel and other pure metals and ferronickel, phosphor bronze alloy; semiconductor thermometers are mainly used carbon, germanium and so on. Resistance thermometers are easy to use and have been widely used. Its measurement range is around -260°C to 600°C. ? 3, thermocouple thermometer: is a widely used industrial temperature measurement instrument. Made using thermoelectricity. Two different wires are welded together to form a working end, and the other ends are connected to a measuring instrument to form a circuit. When the working end is placed at the measured temperature and the working end and free end temperature are different, an electromotive force occurs, so that current flows through the loop. Through the measurement of the electrical quantity, using the known temperature, the temperature of another place can be measured. This kind of thermometer is made of copper—constantan copper, iron—constantan copper, nickelmin—constantan copper, gold-cobalt—copper, platinum—thorium and so on. It is suitable for the two substances with larger temperature difference, and is mostly used for high temperature and low turbidity measurement. Some thermocouples can measure temperatures as high as 3000°C, and others can measure cryogenic temperatures that are close to absolute zero. ? 4, high temperature thermometer: refers to a thermometer specifically used to measure temperatures above 500 °C, photometer thermometer, colorimetric thermometer and radiation thermometer. The principle and construction of high-temperature thermometers are more complex and will not be discussed here. Its measurement range is from 500°C to more than 3000°C and is not suitable for measuring low temperatures. 5, pointer thermometer: is shaped like a dashboard thermometer, also known as the Thermometer, used to measure room temperature, is made of metal thermal expansion and contraction principle. It uses a bimetal as a temperature sensing element to control the pointer. The bimetal is usually riveted together with copper and iron, with the copper on the left and the iron on the right. Because the thermal expansion and contraction of copper is much more than that of iron, when the temperature rises, the copper pulls the iron piece to the right, and the pointer deflects to the right (points to high temperature) under the driving of the bimetal; As the temperature becomes lower, the pointer is deflected to the left (pointing to low temperature) driven by the bimetal. 6, glass tube thermometer: glass tube thermometer is the use of the principle of thermal expansion and contraction to achieve temperature measurement. Due to the difference in the expansion coefficient of the temperature measuring medium, the boiling point and the freezing point, our common glass tube thermometers mainly include kerosene thermometers, mercury thermometers, and red pen water thermometers. His advantages are simple structure, easy use, relatively high measurement accuracy and low price. The disadvantage is that the upper and lower limits of the measurement and the accuracy are limited by the quality of the glass and the properties of the temperature measuring medium. And can not be far away, fragile. 7. Pressure type thermometer: The pressure type thermometer uses the liquid in the closed container, and the gas or saturated vapor is heated to produce a volume expansion or pressure change as a measurement signal. Its basic structure is composed of three parts, a warm package, a capillary tube, and an indication table. It is one of the earliest methods used for temperature control in the production process. Pressure-based temperature measurement systems are still a very widely used measurement method for on-site indication and control of temperature. Pressure thermometers have the advantages of simple structure, high mechanical strength, and no fear of vibration. It is inexpensive and does not require external energy. Disadvantages are: temperature measurement range is limited, generally -80 ~ 400 °C; heat loss, large response time is slow; instrument sealing system (warm package, capillary, spring tube) damage is difficult to repair, must be replaced; measurement accuracy by the ambient temperature, The installation position of the temperature package has a great influence and the accuracy is relatively low; the capillary transmission distance is limited. 8, rotary thermometer: Rotary thermometer is made of a curled bimetal. One end of the bimetal is fixed and the other end is connected with a pointer. Due to the different degree of expansion of the two metal pieces, the degree of curling of the bimetal is different at different temperatures, and the pointer is then pointed at different positions on the dial. From the reading on the dial, the temperature can be known. 9, semiconductor thermometer: semiconductor resistance changes and the metal is different, the temperature rises, but its resistance is reduced, and the change is greater. Therefore, a small amount of temperature change can also make a significant change in the resistance, the thermometer has a higher precision, often referred to as a temperature sensor. 10. Thermocouple Thermometer: A thermocouple thermometer consists of two sensitive metals connected by a sensitive voltmeter. Metal contacts produce different potential differences at both ends of the metal at different temperatures. The potential difference is very small, so you need a sensitive voltmeter to measure it. From the reading of the voltmeter, you can know what the temperature is. 11, optical pyrometer: If the object temperature is high enough to emit a large amount of visible light, you can use the measurement of the amount of heat radiation to determine its temperature, this thermometer is a photometric thermometer. This thermometer is mainly made of a telescope with a red filter and a set of circuits with a small bulb, an ammeter and a variable resistor. Before use, establish the relationship between the temperature corresponding to the different brightness of the filament and the reading on the ammeter. When using, align the telescope with the object to be measured and adjust the resistance so that the brightness of the bulb is the same as the object to be measured. At this time, the temperature of the object to be measured can be read from the ammeter. 12, liquid crystal thermometers: liquid crystals made with different formulations, the phase transition temperature is different, when its phase change, its optical properties will change, so that the liquid crystal looks like it has changed color. If liquid crystals with different phase transition temperatures are applied to a piece of paper, the temperature can be known from the change in the color of the liquid crystal. The advantage of this thermometer is that it is easy to read, but the disadvantage is that it is not accurate enough. It is often used in ornamental fish tanks to indicate the water temperature. The above is an analysis of the types of thermometers that we will introduce to everyone. I hope everyone can help! The grill rack chicken leg wrings great for Use in the Oven, Smoker, or on the Grill. Multi-Purpose 12 Slot Leg and Wing Rack for Poultry. 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What are the types of thermometers