Sensors • Temperature Sensors • Thermocouples

 A thermocouple is a junction between two different metals that produces a voltage which is related to a temperature difference. Thermocouples can be used as temperature sensors or as instruments that convert heat into electric power, although most units cannot achieve an accuracy better than within one degree Celsius. Common applications for thermocouples include diesel engines, kilns, gas furnaces, and other scientific and industrial processes.Thermocouples are made in a variety of alloys with varying sensitivities and other characteristics. For example, Type K chromel-alumel is the most common and general purpose, type E chromel-constantan is non-magnetic and high output for cryogenic use, and types B, R, and S platinum-rhodium are suited for high temperatures, but are also the least sensitive.Leading manufacturers: Watlow, Omega Engineering, Nordic Sensors, Pyromation and Nanmac. 

Filter by state

  • C-Temp International

    C-Temp International offers mineral-insulated, plastics industry, and cut-to-length thermocouples. Mineral-insulated parts are manufactured from 0.010" to 0.5" diameter, with a variety of sheath materials such as 304SS, 310SS, 316SS, Hastelloy X, Iconel 600, Iconel 601, Iconel 702, molybdenum, and tantalum.

  • Precision Measurements, Inc.

    A wide range of thermocouple types are carried and sold by Precision Measurements. Among their products are magnesium oxide insulation, metal-sheathed thermocouples, as well as bayonet thermocouples in flex hose type and spring type. The spring type is more flexible and provides more tension than the flex hose type. Fixed length bayonet type thermocouples are also available.

  • Watlow

    Watlow carries an array of thermocouples. General application styles include adjustable spring type thermocouples that fit a large range of hole depths and bend to any angle, and armor style thermocouples with stainless steel hoses that offer additional lead protection in demanding applications. Mineral-insulated thermocouples come in the basic cut and stripped style, wafer head Style AS, and thermowell-compatible Style AT.

  • ARi Industries

    Ari Industries offers a wide selection of thermocouples. Their standard/base metal thermocouples come with high purity MgO insulation to provide EMF stability and to minimize drift problems. Multi-level thermocouples are manufactured small enough to replace single-point thermocouples and large enough to replace thermowells.

  • Convectronics

    Convectronics designs an array of thermocouple types to meet almost any application need. Bare wire thermocouples are available in 6 standard configurations. Fixed and adjustable bayonet thermocouples are offered in standard J, K, T, and E base metals. Other types include nozzle, bolt style, metal sheath/MI, paddle, lug and washer, bearing, ribbon, sabre, refractory metal/ceramic, and noble metal thermocouples.

  • Omega Engineering, Inc.

    Omega Engineering carries a wide range of thermocouple styles, including fine gage bare wire and insulated, magnetic, cement-on and self-adhesive, PFA-coated, high temperature, non-contact infrared, handheld, and industrial. Some of the fine gage bare wire and insulated thermocouples include the ready-made insulated 5LRTC and 5SRTC Series constructed with Kapton, PFA, and glass braid insulation, as well as the hermetically-sealed, tip-insulated HSTC Series. Self-adhesive units include the SA1XL Series 5-pack that feature response times <0.15 s, and the HFS Series thin film heat flux sensor. The SS Series, meanwhile, is 0.01 PFA-coated to be chemically inert, electrically insulated, and abrasion-resistant.

  • Cole-Parmer

    Cole-Parmer stocks a variety of thermocouple instruments and probes. Among their featured products is the Digi-Sense thermocouple scanning thermometer with 12-channels; this unit stores and recalls up to 4,680 sets of readings along with time and date, and achieves accuracies of +/-0.1%. Another choice is the Oakton Acorn thermocouple thermometer in J, K, or T types, and a temperature range from -250 to +1,372 degrees Celsius; included is a protective rubber boot with a built-in stand for benchtop use. The company also carries Type K general purpose probes that feature a temperature range from -250 to +899 degrees Celsius, as well as several benchtop, wall mount, and handheld thermocouple meters.

  • DCC Corp

    DCC Corporation manufactures a broad range of thermocouple wires, welders, and data loggers that allow customers to make their own thermocouples. Wires come in either solid or stranded types that have a maximum temperature range between 500 and 900 degrees Fahrenheit, and are available in an assortment of materials such as platinum rhodium and tungsten rhenium. Two types of welders are also sold, the HotSpot I and II, which generate electric arcs for fusing standard couple elements into freestanding beads and welding them to any thickness base metals; the main difference between the two is that the HotSpot II can handle heavier wires, up to 14 gauge. Finally, DCC sells HotMux thermocouple data loggers that monitor thermocouple and other analog signals using digitizing 8-channel modules, and can display, print, and store data via an attached desktop of laptop.

  • Furnace Parts LLC

    Furnace Parts manufactures MgO, base metal, and high temperature thermocouples, in addition to a variety of related accessories. Available in types E, J, K, N, and T, the MgO metal-sheathed units come in standard diameters of 0.063", 0.125", 0.188", 0.25", and 0.375" with several connection head and mounting fitting choices. Base metal thermocouples are offered in a variety of wire sizes and configurations, as well as with customizable lengths, insulators, heads, plugs, jacks, blocks, and flanges. Type R, S, B, and C high temperature thermocouples are also made by Furnace Parts; they come with a choice of ceramic, Inconel, Hastelloy, and Molybdenum sheaths. These three types of thermocouples can be applied to a wide range of industries, including steel and specialty metal fabrication, oil and gas, heat treating and thermal process, and aerospace.

  • Lake Shore Cryotronics

    LakeShore specializes in thermocouple sensors for use in cryogenic applications. Choices include the chromel-gold/iron thermocouple, which is widely used because of its relatively high thermoelectric sensitivity (>15 mV/K above 10 K); the Chromel-Constantan Type E, which has the highest sensitivity among the three standard thermocouple types and is the best choice for temperatures down to 40 K; and the Chromel-Alumel Type K, that is recommended for continuous use in inert atmospheres, and offers a sensitivity of 4.1 mV/K at 20 K.

  • Microstrain, Inc.

    Under its Low Duty Cycle Series, Microstrain features three thermocouple model nodes. The TC-Link 6-channel wireless node is complete and cold junction-compensated, and either transmits data in real time or logs data to 2MB with a 2.4 GHz IEEE 802.15.4 spread spectrum radio. The TC-Link 1-channel wireless thermocouple node, which offers many of the same features as the previous product, provides sample rates from 2 Hz to 1 sample every 17 minutes. Lastly, the TC-Link OEM wireless node is embeddable and includes a self-calibrating 24 bit sigma-delta analog-to-digital converter. All three products support J, K, R, S, T, E, B, and N thermocouple types.

  • Nanmac Corp.

    Nanmac offers a variety of thermocouple categories for different applications. Choices include metal sheathed units for general use, including thermocouples with standard plugs in 0.0625" to 0.25" diameters, thermocouples with bare leads available in any length, and thermocouples with conduit heads. Ultra-high temperature products are also sold for use in settings up to 4,230 degrees Fahrenheit, such as graphite furnaces. Spring-loaded thermocouples include 5.83 lbs/in rub & contact units for moving surfaces and drums, and ribbon types that are designed for threaded blind-hold measurements, surfaces subject to vibration or oscillation, and any application where positive contact for good measurement is required.

  • Nordic Sensors, Inc.

    Nordic Sensors Industrial specializes in thermocouples and other temperature measurement products like RTDs, thermowells, wires, hardware, controllers, and accessories. Thermocouples come in one of three categories. General purpose models are offered in adjustable bayonet, fixed bayonet, 45- and 90-degree bend, nozzle bolt, ring terminal, shim stock, and many other styles. Thermocouples for industrial processes include the hot runner, melt bolt (e.g. rigid, fixed, adjustable), mineral insulated, and 45- and 90-degree bend styles, among others. Heavy duty and special application thermocouples and related products include stepped or straight threaded thermowells, tapered threaded thermowells, nipple-union-nipple thermowells, bare element thermocouples, and noble metal thermocouples.

  • Thermal Corporation

    Thermal Corporation designs and manufactures a variety of thermocouples, ranging from cryogenic models to 5,000-degree Fahrenheit-appropriate models. They offer, for example, a series of type J universal bayonet thermocouple probes in four configurations that come in lengths from either 36"- or 48"-long, to 120" long, feature a standard adjustable locknut, and include an 8" spring on two of the models. They also make universal thermocouple extensions in seven configurations (e.g. stainless steel overbraid with jack on one end and mini-plug on other end, stainless steel flexible hose with spade terminals on one end and jack on other end, etc.) made from 20-gauge stranded thermocouple wire, in types J or K.

  • Durex Industries

    Durex Industries supplies a wide selection of industrial process thermocouples to meet demanding process applications like steel processing, turbine and diesel engine temperature measurement, and chemical processing, as well as for commercial applications like food service, packaging, and semiconductor packaging. Platinum thermocouples, most commonly ANSI types R, S, and B, are used for high temperature applications, while mineral-insulated thermocouples can be made to all standard ANSI calibrations, with sheath diameters from 0.02" to 0.5" and temperature tolerance up to 2,400 degrees Fahrenheit. Miniature thermocouples are also available in addition to multi-point thermocouples for pipelines, process towers, boilers, and vessels where multi-point monitoring is important.

  • JOBCO, Inc.

    JOBCO offers a variety of thermocouples, including bayonet tip-spring-cap, hot runner, K-type, and melt probe models. Over 20 models of bayonet tip-spring-cap thermocouples are available, include ungrounded units with tips bent at 90 degrees and units with L-clamp relief springs and caps. The one hot runner product offered comes with a 4 mm outer diameter, 240" length, and 7" strain relief spring. By contrast, K-type thermocouples come in several sizes, and are made with nickel-chromium and nickel-aluminum lead wires, while five models of melt probe thermocouples are sold for use in OEM. Unlisted configurations can also be accommodated by contacting the company directly.

  • Temperature Specialists, Inc.

    An assortment of thermocouple assemblies are available through Temperature Specialists. Connector-style, transition-style, tube and wire, and bayonet-style units provide a choice of element type and accuracy, single- or dual-junction, sheath diameter, and sheath tip styles (e.g. standard, round, flat, angled, drill point, pointed, etc.). Both tube and wire- and bayonet-style thermocouples are available straight or bent at 45- or 90-degrees, while all styles except for connector are offered in either solid or stranded wires. The choice of leadwire insultations is broad, as well, including TFE Teflon, fiberglass or hose, ceramic fiber, PVC, FEP Teflon, and PFA Teflon.

  • Thermal Devices

    Thermal Devices offers multiple thermocouple designs for various industries. Plastics industry thermocouples come in a variety of braided or armored leads, from 48" to 96", while variable depth, armor-style thermocouples come in type J standard, lengths from 48" to 144", and stainless steel armor leads standard. Surface mount thermocouples are offered in type J and ring lug style, as well as in 72" and 120" sizes. Another type is the MgO thermocouple for temperatures to 2,200 degrees Fahrenheit, and for even hotter temperatures, an ultra-high temperature thermocouple made from platinum.

  • Thermocouple Technology, Inc.

    Thermocouple Technology (TTEC) provides TECPAK MgO thermocouples, power industry thermocouples, process industry thermocouples, and more. The TECPAK products come in 0.02" to 0.626" diameters, and sheath materials like 304, 310, and 316 stainless steels and Iconel 600. Power industry thermocouples are meant for demanding applications that might be found in power plants, with designs suited to boiler tube, bearing temperature, turbine test, gas sampling multipoint, vibration resistant, and other uses. Another thermocouple sold by TTEC is for industrial and high temperature applications; these units utilize ceramic protection tubes with noble metal elements for optimum performance at temperatures ranging from 2,000 to 3,100 degrees Fahrenheit.

  • Therm-X

    Therm-X carries a range of thermocouples such as the KF flange vacuum thermocouple, TC exposed junction beaded wire thermocouple, and monitored wafer thermocouple. The KF is mineral-insulated, and its flange allows sensors to be fed into a vacuum chamber, while the TC provides N.I.S.T. traceability and wire with special limits of error. The MW is ideal for measuring balance of temperature throughout a wafer, and uses 36 gauge wire for efficient response times. In addition to these sensor types, other models include tube and wire, Teflon-covered, foil cement, washer, transition, and self-adhesive thermocouples.