Thermocouples Manufacturers online

21 Exporters
20 Manufacturers
1 Distributors

Thermocouples Suppliers (21)

Manufacturer   Germany   Europe
BACH RC is a family business which responds expeditiously and flexibly to market demands. Our customers are manufacturers of semiconductor processing systems, machine building industries,...
Products: Thermocouples, Temperature Controllers, Platinum Temperature Sensors, Ceramic Components, Radiant Heaters, Industrial Hot Plates, Ceramic heaters
Manufacturer   Germany   Asia Africa Europe
Products: Thermocouples, Shut-Off Valves, Gas Fittings, Gas Hoses, Gas Lights, High Pressure Hoses, Liquefied Petroleum Gas Fittings, Transport racks
Manufacturer   Italy   Worldwide
Products: Thermocouples, Optoelectronic Sensors, Optoelectronic Laser Sensors, Temperature Controllers, Laser Light Barriers, Line Sensors, Miniature sensors
Manufacturer   Germany   Europe
The company electrotherm GmbH is specialized in development, design and manufacturing of resistance thermometers and thermocouples. Applications with connection head or connection cable, mineral insul...
Products: Thermocouples, Thermocouple Measurement Instruments, Temperature Meters, Transmitters, Calibrating Services, Cable Sensors, Fixed-Point Cells
Manufacturer   Germany   Worldwide
More than 60 years of experience in temperature measurement and control technique as well as in cable production have made a one man business a...
Products: Thermocouples, Flexible Cables, Hybrid Cables, Control Lines, Electric Wiring Harnesses, Halogen Free Cables, Temperature Probes, Cables & Lines
Manufacturer   Germany   Worldwide
Precision, quality and versatility - these are the standards that have marked the development of this medium-sized family business over the last forty-five years into...
Products: Thermocouples, Threshold switches, Length Gauges, Acceleration Sensors, Displacement Meters, Panel Meters, Tensile Testing Machines
Manufacturer   Switzerland   Worldwide

Endress+Hauser is a global leader in measurement instrumentation, services and solutions for industrial process engineering. We provide process solutions for flow, level, pressure, analytics, tempe...

Products: Thermocouples, Threshold switches, Conductivity Meters, Conductivity Sensors, Temperature Meters, PROFIBUS Fieldbuses, Oxygen Sensors
Manufacturer   China   Worldwide
Products: Thermocouples, Thermocouple Cables, Temperature Sensors, Resistance Temperature Sensors
Manufacturer   Japan   Worldwide
Products: Thermocouples, Hygrometers, Temperature Meters, Thickness Gauges, Humidity Sensors, Measuring & Test Equipment, Recorders, Temperature Controllers
Manufacturer   Germany   Worldwide
Products: Thermocouples, UV Meters, Hygrometers, Vane Anemometers, pH Electrodes, Differential Pressure Gauges, Sound Level Meters
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Thermocouples manufacturer

General information about thermocouples

Over the years, the development of temperature measurement technology has produced numerous different measurement methods for temperature measurement. Mineral insulated temperature sensors as sheathed thermocouples belong to the group of temperature sensors, which cover a wide range of applications as proven resistance thermometers.

Function Principle Thermocouples

With thermocouples, different metals are joined together at a certain distance, usually by soldering joints. One connection point represents a measuring point, the other serves as a reference point. If different temperatures prevail at these two connection points, an electric thermoelectric voltage is generated between these contact points, which allows a small but measurable current to flow. This phenomenon is also known as the Seebeck effect.

Cause of the thermoelectric emf

Metals as chemical raw materials consist of atoms in whose atomic shells the electrons move on different paths around the atomic nucleus. The outer shell of each atomic shell is occupied by valence electrons. These valence electrons are bound to the atomic nucleus with a very specific binding energy, whereby the size of the binding energy varies for different metals. If this binding energy is overcome by external energy input in the form of heat, valence electrons of the metal with the smaller binding energy at the solder joint can jump over to the metal with the larger binding energy. There an excess of electrons is created, and the metal with the lower binding energy has an electron deficiency. The resulting potential difference is the cause of the thermoelectric emf, on which the functional principle of a thermocouple is also based.

Physical details on the magnitude of the thermoelectric emf

The Seebeck coefficient (S), which is specified in microvolts/Kelvin (µV/K), plays a decisive role for the magnitude of the thermoelectric emf. The product of the Seebeck coefficient multiplied by the temperature difference gives the theoretical thermoelectric emf in Kelvin.

The size of the Seebeck coefficient is given for different metals in relation to platinum (Pt). The base temperature is T = 273 K (0 °C).

  • Constantan = -35 µV/K
  • Nickel = -15 µV/K
  • Aluminium = 3.5 µV/K
  • Copper = 6.5 µV/K
  • Silver = 6.5 µV/K
  • Nickel-chromium = 25 µV/K
However, the physical relationship between temperature and thermoelectric voltage is not linear, but approximates the shape of a parabola.


Uth = a * T + b * T2

The coefficients a and b here are thermoelectric material constants. The temperature difference is indicated here with T, at a reference temperature of T0 = 273 K (0 °C).

Types and applications of thermocouples

Manufacturers of thermocouples differentiate between types K, N, J, E, T, R, S and B. These types are intended for different application and temperature ranges and are sorted according to the following definition:

  • Type K: NiCr-NiAl thermocouples are suitable for oxidizing or protective gas atmospheres up to 1200 °C.

  • Type J: Fe-CuNi thermocouples are used in vacuum, in inert gas atmospheres and for oxidation and reduction applications up to 750 °C.

  • Type N: NiCrSi-NiSi thermocouples are used in oxidizing atmospheres, inert gas atmospheres and dry atmospheres up to 1200°C. The accuracy at high temperatures is very high. However, the atmospheres must not contain sulphur.

  • Type E: NiCr-CuNi thermocouples can be used in oxidizing or inert gas atmospheres up to temperatures of 900 °C. Type E achieves the highest thermoelectric voltage of all thermocouples.

  • Type T: Cu-CuNi thermocouples can also be used at temperatures below 0 °C up to 350 °C in oxidizing, reducing and inert gas atmospheres. They are also insensitive to rust in humid atmospheres.

  • TYPE S: Pt10%Rh-Pt thermocouples are suitable for continuous use in oxidizing or inert gas atmospheres up to 1600 °C. Impurities must be avoided as they cause brittleness.

  • Type R: Pt13%Rh-Pt thermocouples can be permanently used in oxidizing or inert gas atmospheres up to 1600 °C. Contaminating influences must be avoided to avoid embrittlement.

  • Type B: Pt30%Rh-Pt6%Rh thermocouples can be permanently used in oxidizing or inert gas atmospheres up to 1700 °C. In the short term, they can also be used in vacuum environments. Contaminating influences must be avoided to avoid embrittlement.

Conclusion

Heating conductors and heating elements must operate in the correct temperature range in practical applications. Thermocouples often serve here as monitoring and control elements and are successfully used for such purposes.