/ / How and what makes temperature measurement

How and what is the measurement of temperature

Temperature change control (otherwisespeaking, thermometry) is required in laboratory or chemical studies to comply with the technology of processes in production or to ensure the safety of products.

temperature measurement
It is logical to assume that the technologies used in production will not be suitable for domestic purposes. Let's get acquainted closer with the devices allowing to take measurements in various conditions.

By far the most common devicesallowing to measure temperature, these are thermometers. These include meteorological and laboratory, medical and electrical contact, technical and manometric, special and signaling. The total number of modifications is several dozen.

Methods and devices for determining temperature

Usual thermometers for us are only a small partof all existing devices or devices that are used in a situation where temperature measurement is necessary. The determination of the value of thermal indicators can be carried out by several methods. The principle of operation of each device is a specific parameter of a substance or body. Depending on the range in which it is necessary to measure temperature, different devices are used.

  • Pressure. Its change allows you to track temperature fluctuations in the range from -160 degrees to +60. The devices are called pressure gauges.
    temperature measurement methods
  • Electrical resistance.It is the basic principle of operation of electrical and semiconductor thermometers for measuring resistance. The difference in readings allows semiconductor devices to take measurements in the range from -90 degrees to +180. Electrical devices can fix from -200 to +500 degrees.
  • Thermoelectric effect is leadingproperty of standardized or specialized thermocouples. Devices of the standardized type provide determination of temperature limits from -50 to +1600 degrees. Specialized devices are designed to work with critical high rates. Their working range is from +1300 to +2500 degrees.
  • Thermal expansion Used in liquid thermometers, allowing to determine temperatures in the range from -190 to +600.
  • Heat radiation. Underlying the work of pyrometers of various types. Depending on the type of device, the temperature range varies.
    air temperature measurement
    Особое внимание следует обратить на то, что эти devices are only suitable for measuring high positive readings. At color pyrometers, the working temperature limits are 1400 - 2800 degrees. For radiation devices, these figures will be equal to 20 - 3000 degrees. Photovoltaic devices record a temperature of 600-4000, and optical pyrometers will estimate readings within 700-6000 degrees.

Naturally, the question is howThus, the physical properties allow the measurement of air temperature or hot metal. In manometers, the pressure of a gas or liquid is taken as a basis at a certain temperature regime. Pyrometers and thermal imagers allow us to estimate the temperature of the surface of an object, perceiving the thermal radiation emanating from it (pyrometers show the data in digital form, the thermal imager produces a “picture” of the object and its temperature). The use of the thermoelectric effect is in the design of the thermocouple. By and large, the thermocouple is a closed electrical circuit of two different conductors. A certain temperature exposure causes a certain voltage. A similar principle is applied in resistance thermometers.

In general, methods for measuring temperature can be divided into contact and non-contact. The most common example of a contact method is a medical thermometer; a non-contact method is a thermal imager.