The French leader and world renown

Technological mastery in design and manufacturing

Experienced engineers and technicians

Powerful IT systems

A rapid response with method and precision

Founded in 1929 and located in Douai, SADTEM is an independent private company, specialised in the manufacture of metering and protection transformers for medium voltage, indoor and outdoor applications.

Recognised throughout the world for its range of products, its technical expertise in design and manufacturing as well as its quality of service, SADTEM is in the unique position of being able to provide a quick, standardised and specific response to every request.

The experience of its engineers coupled with the effectiveness of its IT systems (calculation, design, production, testing) makes it possible to supply sophisticated products to demanding users all around the world.

SADTEM represents 90 years of recognised experience and has a sophisticated understanding of the operating conditions faced by every one of its customers, as well as expertise in the use and control of complex materials while respecting the environment.

SADTEM dedicates a large budget to research and development in order to ensure that its facilities remain at the cutting edge of the latest technological advances. In addition to its own resources, SADTEM works closely with the leading European test laboratories, engineering schools and technology universities.


transformers manufactured for 5 years


% of export sales


countries delivered in 2021


employees at 4 sites in France


% increase in gross sales in 2021

Quality manufacturing that respects the environment

For more than 70 years, we have acquired expertise in the various molding processes for synthetic resins and their fields of use. This expertise allows us to offer you the best technical solution suitable for your application.

The flexibility and precision of our production organization, combined with the panoply of technical, human and material resources available in our factories, allow us to deliver repetitive series of several thousand units and specific parts in small numbers.

The use of largely automated production machinery and equipment in winding, molding and electrical testing operations gradually eliminates heavy or tedious work in favor of more rewarding tasks and increases product quality reliability.

Manufacturing is organized in full compliance with current environmental legislation.

The highly computerized production management and monitoring make it possible to monitor and manage in real time the production of orders in progress as well as production capacities and costs.

Strict and systematic controls

They are carried out systematically on all devices, and other checks can be carried out at the customer's request. SADTEM's laboratories and test platforms allow, in addition of standardized routine tests, the performance of most type and durability tests prescribed by international standards:

  • Impulse voltage up to 500kV,
  • Industrial frequency tests
  • Accuracy measurements at 50, 60, 16 2/3 or 25 Hz,
  • Temperature rise test
  • Ageing test under voltage with exposure to UV rays, rain and salted fog
  • Climatic test down to -50°C

State-of-the-art, computer-driven automatic test facilities ensure rigorous monitoring of routine tests and immediate delivery of written test protocols in the appropriate language. In addition to the tests prescribed by the international standards in force, we carry out numerous checks both upon receipt of raw materials and during manufacture, in order to detect, isolate and treat any part presenting a risk of defect.

Bureau Veritas

Our ISO 9001 certification

Quality control is confirmed by ISO 9001 certification.

Quality control and customer satisfaction are the best investments we can make.

A unique & fast manufacturing process

Study & analysis of your project

Design of your specifications

Manufacture and verification of your product

A presence all over the world

Customers who trust us

For more than 90 years, SADTEM has experienced continual development for export to more than 80 countries and for more than 80% of its production, relying on a perfect knowledge of the specificities of each market, country, standards and habits, a global network of competent agents, and thousands of devices in service everywhere in the world, in all climates and all environments. Among them :

  • Electricity production and distribution companies
  • Manufacturers of electrical equipment for the production, transmission, distribution and metering of electricity
  • Major energy-consuming industries (steelworks, refineries, aluminum electrolysis, etc.)
  • Rail transport companies
  • Electrical and industrial engineering companies








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