Temperature sensors are technical devices designed to continuously measure the temperature of an object or substance using the properties of controlled media. The use of industrial temperature sensors allows you to: control the speed and level of heating of liquid, solid and gaseous media, monitor thermodynamics in various conditions. The devices are used in the equipment of boiler houses, heating systems, industrial units, in housing and communal services and agriculture.
Operating principle of sensors
The main tasks of these devices integrated into automatic control systems are to measure the temperature of an object or substance and convert a physical quantity into an electrical signal. Converting temperature to electrical value provides the following benefits:
- possibility of high-speed transmission of measurement results over long distances;
- if necessary, reverse transformation of electrical quantities into physical ones;
- high measurement accuracy.
Design options for temperature sensors
These devices, according to their design and principle of operation, are divided into the following types:
- Thermoelectric are the most common measuring devices. Their operation is based on the thermocouple principle. For high-temperature environments (up to +2000°C), you should buy a tungsten-rhenium temperature sensor. Platinum-rhodium-platinum-rhodium sensors are characterized by high measurement accuracy, and therefore are widely used in laboratory measurements. Chromel-alumel devices are used in industrial conditions up to +1200°C, copper constantan devices — up to +400°C. Models of the latter type are resistant to humid environments and some aggressive environments.
- Semiconductor. They are produced on the basis of crystals with a certain current-voltage characteristic. A semiconductor is usually used for measurements by connecting it through an amplifier circuit. The advantages of a semiconductor device are high accuracy and a wide measurement range, compact dimensions.
- Pyrometric. Pyrometers are sensitive elements that quickly respond to the slightest temperature fluctuations. Pyrometers are the basis for non-contact thermometers used for thermal imaging monitoring of people, buildings, and equipment.
- Thermistor. The basis of their design is thermistors, the resistance of which depends on the temperature of the controlled object or substance. Such sensors provide high measurement accuracy. To expand the temperature range, the device is connected to an amplifier circuit.
- Piezoelectric. The operating principle of the device is based on changing the oscillation frequency of a quartz crystal through which an electric current passes, depending on changes in temperature conditions.
Features of choosing a suitable sensor
Temperature sensors can be surface-mounted or immersed, contact and non-contact, wired and wireless.
Before purchasing a measuring device, you must determine:
- type of controlled environment;
- measurement accuracy class;
- location of the meter;
- method of reading and transmitting measured values.
Benefits of cooperation with STEMAG GROUP
In company STEMAG GROUP you can choose from the catalog and buy temperature meters, price — on request, delivery to the countries of the Middle East and Central Asia is possible.
STEMAG GROUP provides:
- sale of certified temperature sensors and other instrumentation with the required technical characteristics;
- consulting support;
- compliance with contractual deadlines.
