History
Our history
Today, Isabellenhütte Heusler is a highly innovative company with a long tradition - it is considered the oldest industrial company in Hessen. As early as 1482, a copper smelter was mentioned in documents at the current location in Dillenburg. In 1728, the company was given its current name when Princess Isabella received this copper smelter as a dowry from her husband Prince Christian von Nassau-Dillenburg and renamed it “Isabelle Kupferhütte”.
Since 1827, Isabellehütte has been run as a family business by the Heusler family. Carl Ludwig Heusler, then head of the Siegen mining school, ran the company until his death in 1851. Under his sons, Isabellenhütte expanded its copper production and began manufacturing nickel silver.
A significant breakthrough was achieved in 1889 with the development of the alloy Manganin® in collaboration with the Physikalisch-Technische Reichsanstalt (PTR), which became of fundamental importance for metrology. In 1898, the secret miner Conrad Heusler founded “Isabellenhütte GmbH”, which was based on manganese bronze, Manganin® and resistin for various applications in railroads, electrical engineering and shipbuilding.


In 1901, Dr. Fritz Heusler, the director of the company at the time, discovered the Heusler alloys named after him. These ferromagnetic alloys were further researched in collaboration with the Philipps University of Marburg and published in 1933.
Over the decades, we have continuously modernized our company and opened up new production areas. A wire drawing plant was added in 1952, an insulating plant in 1960 and a hot rolling mill in 1980. These modernizations enabled us to specialize in low-resistance precision and power resistors as well as resistance and thermal alloys.
Today, we are a global high-tech provider and one of the world's leading manufacturers in three business areas:
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Alloys:
Our resistance and thermal alloys, manufactured to international standards, are used in temperature sensors, thermocouples and immersion probes and are supplied in various formats such as wires and sheets. -
Resistors:
We manufacture high-precision, low-ohm resistors for the automotive industry, including motor control units and energy management systems. Our products are also used in power electronics, telecommunications, medical technology and aerospace. -
Sensors:
We are one of the leading providers of modern, shunt-based current measurement systems. Our innovative current measurement sensors are used in racing, Formula E and electric vehicles as well as in smart grids, charging stations and substations.
With offices in key locations around the world, we continue to strengthen our global presence and commitment to innovation. In 2019, we expanded our production capacities and relocated our ISA-WELD® production to Manderbach, where we have been producing alongside our main production site in Dillenburg since 2021. Other well-known brands of our company are Isabellin®, Manganin®, Zeranin® and Isaohm®.
To further strengthen our innovative power, we invested four million euros in the construction of a new logistics center in 2020, which offers state-of-the-art infrastructure and optimized logistics processes. At our development site in the innoCampus technology building in Bochum, which was opened in 2023, we are also researching the latest innovations in the fields of measurement technology and smart grids.
Today, we combine tradition and progress and are shaping the future with highly innovative technologies.