eXacal Precision Thermometers
Table of Contents
Resistance Thermometers and Thermocouples
eXacal precision thermometers measure precise temperatures from -200 °C to 1200 °C and serve as a reference for the calibration of other thermometers. Depending on the application, they are available as Standard Platinum Resistance Thermometers (SPRT), Pt100 resistance thermometers, or noble metal thermocouples.
We handcraft them in our manufactory in Fulda: from design to the construction of the temperature sensor and accredited calibration according to DIN EN ISO/IEC 17025 (DAkkS).
Highlight · High End · ITS-90
Primary ITS-90 SPRT – Our High-End Thermometer
-200 °C to 670 °C
The primary Standard Platinum Resistance Thermometer meets all requirements of ITS-90 (International Temperature Scale of 1990).
It is designed for maximum accuracy, representing the highest level of precision thermometry – ideal as a primary calibration standard in research, national metrology tasks, and wherever the lowest possible measurement uncertainty is required.
Secondary SPRT – The Robust Alternative for Daily Laboratory Use
The secondary SPRT is the more robust alternative for daily use in the laboratory.
It does not meet all ITS-90 requirements but still offers excellent accuracy and long-term stability.
This makes it the right tool for all demanding everyday applications where a stable, reliable, and less sensitive SPRT is needed.
Our secondary SPRT models at a glance:
Secondary SPRT Reference Thermometer
(-200 °C to 250 °C)
Secondary SPRT Reference Thermometer
(-100 °C to 430 °C)
Secondary SPRT Reference Thermometer
(-100 °C to 670 °C)
Precision Thermometers
Our precision thermometers are ideal as temperature standards for calibrations or for accurate temperature measurements. Available as resistance thermometers (Pt100) and as noble metal thermocouples of types R/S/B, Pt/Pd, and Pt/Au. Our eXacal precision thermometers are a robust alternative to the extremely sensitive ITS-90 Standard Platinum Resistance Thermometers (SPRTs). The eXacal thermocouples are manufactured with a stainless steel reference junction.
Industrial Reference Thermometers
Industrial reference thermometers (Pt100 and noble metal thermocouples) are perfect for industrial use in traceable temperature measurements or as secondary standards for industrial calibrations (for example, in a temperature block calibrator).
Models:
Pt100
Pt100 Model I (-100 °C to 250 °C)
Pt100 Model IN (-100 °C to 400 °C)
Pt100 Model IH (-100 °C to 660 °C)
Noble Metal Thermocouples
Thermometers for Special Applications
Special designs: We also manufacture precision thermometers according to your individual requirements, for example, differential thermometers, angled temperature probes, and thermometers according to specific customer requests.
Models:
Precision Thermometer Pt100 Model M (-100 °C to 250 °C)
for immersion depth investigations and fast measurements
Type R / Type S Temperature Differential Thermocouple (0 °C to 1200 °C)
Pt100 Type D Temperature Differential Thermometer (-100 °C to 250 °C)
Do you have questions about our precision thermometers?
Speak directly with our expert!
Your contact person for precision thermometers:
Elke Seewald
Head of the eXacal Manufactory at Klasmeier
Thermometer Manufactory – Handcrafted Precision Thermometers
Our eXacal precision thermometers are handcrafted with the utmost care in our manufactory in Fulda, Germany – also custom-made to your individual requirements if desired. Whether adjustments to the handle, connector, probe length, or connection cable – we precisely implement your wishes.
Our thermometers are developed for accurate temperature measurements and cover, depending on the model, a wide temperature range from -200 °C to 1200 °C.
In addition to thermometer design, we place particular emphasis on the development of our own tools and innovative production processes. From design to manufacturing and final accredited calibration according to DIN EN ISO/IEC 17025 (DAkkS), every step is carried out exclusively in-house. Thanks to the use of high-quality raw materials and the absence of external suppliers, we guarantee consistently high quality for our products.
Watch a tour of the thermometer manufactory in the video:
The Manufacturing Process at a Glance
Mechanical Manufacturing
Components such as handles or prototypes for development projects are precisely manufactured using machining.
Precious Metal Welding Process
Thermowires and connection cables are manually welded with the highest precision. The required fuel gases, hydrogen and oxygen, are not stored in cylinders but are generated directly by electrolysis from water in an optimal 2:1 mixing ratio. This process ensures particularly high purity of the fuel gas.
Laser Welding
Filigree connections, such as the connecting wires of temperature sensors, are welded under a microscope with high-precision lasers.
Thermal Treatment of Thermomaterial
A core competence is the targeted thermal treatment of thermowires. Our aging processes ensure a metallurgically stable and thermoelectrically homogeneous state of the eXacal thermocouples.
Aging of Resistance Thermometers
Resistance thermometers are fully stabilized in a specially developed aging oven, flushed with oxygen, according to adapted aging cycles.
Wire Coiling
For SPRT measuring resistors, wafer-thin, high-purity platinum wire is precisely coiled into the finest wire coils using a specially developed winding machine.
Cleaning of Ceramic Components in a Tube Furnace
All ceramic components used in our precision thermometers undergo an intensive cleaning process in a tube furnace at high temperatures before use.
Temperature Sensors – Precision from In-House Production
The manufacturing of temperature sensors is a craft that requires the highest precision and expertise. In our manufactory, we combine state-of-the-art technology with traditional craftsmanship to carry out this complex process entirely ourselves. With great care and experience, our specialists hand-thread wafer-thin platinum wire onto ceramic or quartz carriers under a microscope. Previously, the wire is formed into a delicate coil on a winding machine, which serves as the basis for our highly sensitive temperature sensors. These sensitive components form the heart of our products. In our thermometer manufactory, they are further processed and refined into precision thermometers of the highest quality – for accurate measurement results you can rely on.
Modern 3D Printing Technology
Our eXacal thermometers utilize high-precision insulation elements and complex plastic components, such as strain reliefs. These components are manufactured directly in our production using state-of-the-art 3D printing technology. This allows even demanding geometries to be implemented without additional tools or manual intermediate steps. This not only saves time and costs but also enables flexible and customer-specific manufacturing of our modular thermometers.
Inhomogeneity Scanner
The investigation of possible inhomogeneities in eXacal thermocouples is carried out with a specially developed inhomogeneity scanner. A movable heat source checks the entire thermomaterial of the measuring point for local deviations.
The inhomogeneity scanner is an innovative in-house development by Klasmeier and significantly contributes to the optimization of eXacal thermocouples. It enables:
a more realistic assessment of measurement uncertainties
the verification and refinement of thermal treatment processes
a significant improvement in product quality and manufacturing processes
eXacal Technology
The eXacal precision thermometers have been completely redeveloped from the ground up. Every component has been designed with the utmost care and perfectly matched to the others. A central highlight is the innovative handle, which serves as a central technology carrier. Thanks to its modular design, it allows for various combinations of eXacal thermometers.
The Handle as a Technology Carrier
Our eXacal thermometers can be configured almost infinitely as a modular system. This is made possible by our aluminum handle, which is equipped with an individually 3D-printed insert for each thermometer. Important components such as strain reliefs, protective gas fillings, or various protection tubes can thus be freely combined.
Temperature Sensors
Temperature Sensors from In-House Production
In our manufactory, we produce precise temperature sensors. Experienced employees wind platinum wire onto ceramic or quartz bodies. After winding, we form these measuring resistors into precision thermometers.
Thermometer Wire
As thermometer wire for the measuring resistors and in the capillaries, we use noble metals and not commercially available sheathed wires. Depending on the temperature range, these are pure silver or platinum. This reduces thermoelectric effects and parasitic voltages in the thermometer.
Protection Tubes
Protection tubes are selected based on thermal stress and atmospheric conditions. To optimally protect the temperature sensor from mechanical and chemical influences, protection tubes made of pure ceramic, noble metals, high-temperature alloys, or sapphire are used, depending on the application.
Connection Cables
Connection cables for thermocouples and resistance thermometers are assembled by hand. Copper strands made from a low-stress copper alloy, specially cast for our thermometers, are used. A reinforced textile sheath made of heat-treated fiberglass protective tubing, which is highly temperature-resistant, serves as insulation. This protects the individual strands from mechanical stress, high temperatures, and organic solvents.
High-Quality eXacal Carrying Case
All eXacal thermometers are delivered in a case, but can alternatively be ordered with a high-quality aluminum carrying case. The robust case with its adapted foam insert provides good protection for the sensitive thermometers during transport and storage.
Finding the Right Solution for You Together
