
Secure Threaded Mounting
Threaded mounting ensures secure installation and consistent surface contact for accurate, repeatable temperature measurement in industrial equipment.
Threaded Surface Thermocouple for Accurate Metal Surface Temperature Measurement
To obtain accurate surface temperature measurements, it is necessary to use a sensor that remains firmly in place. The TC21 Threaded Surface Thermocouple is designed to ensure reliable temperature monitoring by maintaining direct contact with hot metal surfaces via its threaded mounting system. This secure fit contributes to better measurement stability, reduces temperature variations, and secures consistent performance in tough industrial conditions. Due to its rugged MgO mineral insulated construction, the TC21 is capable of resisting vibration, thermal cycling, and mechanical stress, which makes it suitable for continuous use on heated platens, molds, dies, machine parts, process equipment, and OEM machinery. The TC21 is available with configurable thread sizes, probe lengths, lead-wire insulation, and termination choices, thus delivering a reliable and customizable solution for OEM manufacturers, machine builders, and maintenance professionals who need accurate long-term surface temperature measurements.

Threaded mounting ensures secure installation and consistent surface contact for accurate, repeatable temperature measurement in industrial equipment.

MgO mineral insulated construction withstands vibration, thermal cycling, and harsh industrial operating conditions for long-term reliability.

Optimized sensing tip delivers rapid heat transfer for fast, stable surface temperature measurement and improved process control.

Available with bare leads, standard, miniature, or high-temperature connectors for easy integration with existing control systems

Stainless steel construction resists mechanical wear, corrosion, and continuous production environments for dependable long-term performance.

Configure thread size, probe length, lead wire, insulation, termination, and mounting options to match your OEM application.
Plastic Injection
Plastic Extrusion
Heated Dies & Tooling
Packaging
Automotive Engine
Industrial Process
OEM Machine
Rubber Molding
Review the standard specifications and available configuration options for the TC21 Thermocouple. Sheath diameter, insertion length, thermocouple type, lead wire, insulation, connector style, temperature rating, and optional features may vary depending on the selected configuration and application requirements
Technical specifications, dimensions, ordering information, and configuration options for the TC21 Thermocouple

Installation, wiring, maintenance, and troubleshooting instructions for the TC21 Thermocouple.
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Instructions d'installation, de câblage, de maintenance et de dépannage pour le thermocouple de palier TC21
Download file →Complete your installation with compatible mounting accessories, connectors, and replacement components for the TC21 Thermocouple.

Wire clamp bracket will provide optimum strain relief. Construction allows a large difference in maximum and minimum wire diameter. Compact version especially designed to be used with small wire diameters. All stainless…
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Wire clamp bracket will provide optimum strain relief. Construction allows a large difference in maximum and minimum wire diameter. Compact version especially designed to be used with small wire diameters. All stainless…
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FG: FG-Glass Fiberglass. Individual conductors are insulated with general purpose fiberglass and with an overall fiberglass jacket. It is Most popular and widely applied of all glass insulations. A color-coded fiberglass braid…
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Application Connector for thermocouple and RTD circuits. Suited for small wires and mineral insulated cables. Construction Glass filled high quality thermoplastic body with original thermocouple material pins and spring loaded inserts. Type…
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PFA: Color-coded PFA Teflon® is extruded over each single conductor. The single insulated conductors are laid parallel and insulated with an extruded jacket of PFA Teflon® Key Features Rated for continuous use…
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Connector for thermocouple and RTD circuits. Solid pin design ensures good contact even in demanding applications. Hollow pin design offers a good quality product at competitive pricing for less frequently used connectors.…
Find more…Watch product overview, installation, and application videos for the T21 Thermocouple
PT2M44S
A temperature transmitter takes the temperature data from a sensor, like an RTD or thermocouple, and converts it into a standard signal, usually 4-20mA or 0-10V. This signal can be sent to control systems, PLCs, or monitoring equipment to keep track of temperature in real-time.
Video Transcription: Temperature Transmitter Technology & Application
[00:05] A temperature transmitter is a critical component in industrial automation that converts low-level sensor signals into standardized outputs. This ensures accurate, reliable, and long-distance signal transmission for complex control systems.
[00:14] Thermocouple and RTD sensors are the industry standards for measuring the temperature of processed media. However, in challenging environments—characterized by high temperatures, electromagnetic interference (EMI), or long cable runs—the raw signals from these sensors can degrade.
[00:33] This signal degradation, often caused by wire resistance and electrical noise, can lead to inaccurate readings. To mitigate these issues, temperature transmitters are used to amplify, condition, and convert sensor data into a standardized 4-20mA output, ensuring high-integrity data across the plant.
[00:59] Several signal types are used depending on the application:
4 to 20 mA Analog Signal: The most common standard, highly resistant to noise and ideal for long distances.
0 to 10V: A common analog option, though more susceptible to signal loss over length.
Digital Signals (HART & Modbus): Used for advanced remote communication and diagnostics.
RS485/RS232: Essential for integrating transmitters with PLCs and SCADA systems.
[01:35] The Tempotech TT367 series temperature transmitters are engineered for versatility. They offer precise sensor-transmitter matching and robust protection against interference. Configurable via the HART protocol, these units allow for easy setup and reliable field operation.
[01:56] Key reliability features include open/short-circuit detection, incorrect wiring alerts, and NAMUR NE43 failure standards. The TT367 supports RTD, TC, Ohm, and Millivolt inputs, making it a universal solution for your instrumentation needs.
[02:26] With integrated dot-matrix displays and easy configuration options, our transmitters provide the precision you can trust. Contact our technical sales team today to find the best transmitter for your application.
Open the product configurator to select available options and prepare your configuration.
Find answers to common questions about the TC21 thermocouple
The TC21 is available with 1/4"-20 UNC, M6 × 1.75, and custom thread sizes. The thread should match the existing mounting hole to ensure proper seating, reliable thermal contact, and secure installation without modifying the equipment.
Yes. The TC21 is designed with a threaded bolt mounting that keeps the sensing element securely positioned against the measurement surface. Combined with optional stainless steel overbraid or armor, it is well suited for machinery exposed to vibration and continuous industrial operation.
The TC21 is available with PTFE (260°C) and fiberglass (510°C) insulation. PTFE is commonly selected for general industrial environments, while fiberglass is preferred where the lead wire is exposed to higher ambient temperatures. However wire rating does not reflect operating temperature range, Please check with our Sales team.
Yes. The TC21 can be customized with different thread sizes, bolt lengths, sheath materials, lead wire lengths, insulation types, and connector options, allowing it to replace many OEM threaded surface thermocouples without requiring equipment modifications.
For the best measurement accuracy, install the TC21 using the correct thread size and tighten it according to the equipment manufacturer's recommendations to maintain full contact between the sensing tip and the heated surface. Proper mounting, selecting the appropriate lead wire insulation, and protecting the cable from excessive mechanical stress all contribute to stable, repeatable temperature measurements and longer sensor life.
The TC21 should be tightened securely to ensure full contact between the sensing surface and the measured component without exceeding the recommended torque for the mounting thread. Insufficient tightening can create air gaps that reduce heat transfer and affect measurement accuracy, while excessive torque may damage the sensor or the mounting threads.