Rauscher & Stoecklin
Oil distribution transformers and switching technology for safe power distribution
Rauscher & Stoecklin – Swiss engineering, European manufacturing
Rauscher & Stoecklin brings together all activities related to oil distribution transformers, railway electrification, high-current connectors, service connection systems and switchgear within the R&S Group. With the traditional Swiss site in Sissach and the new plant for oil distribution transformers in Krzeczów, Poland, the group forms a strong competence and manufacturing network for power distribution in Europe.
Since 1919, Rauscher & Stoecklin has stood for Swiss precision, quality and reliability in the electrical industry. Based on this, products and systems are created that are designed for safe, efficient and economical power supply – from secondary substations and distribution grids to railway power supply, industrial plants and building services.
The expansion with the plant in Krzeczów (Poland) specifically strengthens European delivery capability for oil-filled distribution transformers. This enables Rauscher & Stoecklin to cover both technically demanding projects with Swiss engineering depth and volume-driven grid expansion and modernization projects in Central and Northern Europe.
Strengths of Rauscher & Stoecklin at a glance:
Competence center for oil distribution transformers
Development and manufacturing of oil-filled distribution transformers for medium-voltage networks, secondary substations, renewable energy projects and a wide range of industrial applications.
Railway electrification & switching technology
Switches, traction transformers and solutions for railway power systems, metro and tramway infrastructure – ensuring reliable power supply to overhead lines.
High-current connectors & service connection systems
Plug-and-socket systems for mobile machinery, tunnel construction, port facilities and the construction sector, as well as service connection solutions for residential, commercial and industrial buildings.
Swiss engineering, European manufacturing at two sites
Combination of Swiss development and application expertise with extended production capacity in Poland – for short lead times and high planning reliability.
Use in critical infrastructures
Solutions for utilities, industry, data centers, hospitals, airports and other safety-relevant applications.
Visit our production sites
End-to-end logistics that keeps every deadline
„We manage material and information flows end-to-end – data-driven, transparent and with clear priorities to ensure predictable lead times and on-time deliveries.”
Mirjana Milinkovic, Head of Logistics & Production Control, Rauscher & Stoecklin AG
Frequently asked questions
Who is Rauscher & Stoecklin?
Rauscher & Stoecklin is the R&S Group's Swiss brand for oil-cooled distribution transformers, with its main plant in Sissach since 1919 and around 100 employees at the Swiss site. Since April 2025, the brand has also had a second production plant in Krzeczów, Poland.
Which applications does Rauscher & Stoecklin supply transformers for?
Rauscher & Stoecklin supplies transformers for medium-voltage networks, secondary substations, data centres and renewable energy projects as well as for a wide range of industrial applications. Switchgear is also part of the portfolio.
What power range do Rauscher & Stoecklin distribution transformers cover?
At its main Swiss plant in Sissach, Rauscher & Stoecklin manufactures distribution transformers from 100 kVA to 2,500 kVA with a maximum rated voltage of 36 kV; the plant in Krzeczów (Poland) extends the portfolio with oil distribution transformers up to 3,150 kVA and up to 33 kV.
What is the difference between free-breathing and hermetically sealed transformers?
Free-breathing transformers are compact, lightweight and operate without pressure. Hermetically sealed transformers prevent the coolant from coming into contact with air, which reduces maintenance with regard to oil quality. This distinction concerns the design and sealing of the transformer, not the cooling method.
Does Rauscher & Stoecklin offer a warranty on its transformers?
Yes. Rauscher & Stoecklin grants market-standard warranties on its oil-filled distribution transformers and accommodates individual customer requirements.
Which product lines does Rauscher & Stoecklin offer for distribution transformers?
Rauscher & Stoecklin offers five product lines: ECO++ (entry-level line), K-Line (economically optimised, aluminium winding), R-Line (space-optimised), E-Line (energy-optimised, lower losses) and A-Line (amorphous core, particularly low no-load losses).
What is the difference between the K-Line, R-Line and E-Line?
The K-Line uses aluminium windings and is optimised for cost-effectiveness over its service life; the R-Line is designed for the best balance between dimensions and losses; the E-Line is the energy-optimised series with the lowest overall losses of the three lines.
What is a low-radiation transformer?
A low-radiation transformer from Rauscher & Stoecklin has 8 point-symmetrically arranged low-voltage bushings and therefore fully complies with the Swiss ONIR (Ordinance on Protection against Non-Ionising Radiation).
Does Rauscher & Stoecklin also supply transformers for railway applications?
Yes. Rauscher & Stoecklin produces single-phase overhead line transformers for railway operators up to 1,000 kVA, designed for railway grids with 15 kV/16⅔ Hz or 25 kV/50 Hz, as well as audio frequency transformers for ripple control systems in the 200–2,000 Hz frequency range.
What are amorphous transformers and when are they worthwhile?
Amorphous transformers use a core made of amorphous, non-crystalline material, which makes their no-load losses significantly lower than those of conventional cores. Rauscher & Stoecklin offers them in the 400–1,000 kVA range; they are particularly worthwhile where low no-load losses have a strong economic impact.
Which standards and certifications does Rauscher & Stoecklin meet?
Rauscher & Stoecklin is certified to ISO 9001, ISO 14001 and ISO 45001; its transformers undergo routine testing to SN EN 60076 and meet the EU Ecodesign Regulation (EU) No 548/2014.
Does Rauscher & Stoecklin also offer customised special solutions?
Yes. In addition to standard designs, Rauscher & Stoecklin also manufactures customised solutions, for example for special dimensions, high installation altitudes, earthquake resistance or additional monitoring equipment (e.g. PT100 sensors).
Has Rauscher & Stoecklin opened a new plant?
Yes. On 3 April 2025, the R&S Group inaugurated a new plant of around 10,000 m² for oil-cooled distribution transformers of the Rauscher & Stoecklin brand in Krzeczów near Bochnia, Poland.
Why did the R&S Group open a second Rauscher & Stoecklin plant in Poland?
The plant in Krzeczów specifically strengthens delivery capability to Germany, Scandinavia, the Baltic states and other Central and Eastern European markets, and is a strategic building block of the R&S Group's European manufacturing strategy.
Which transformers does the new plant in Krzeczów manufacture?
Under the Rauscher & Stoecklin brand, the Krzeczów plant manufactures oil distribution transformers up to 3,150 kVA and up to 33 kV rated voltage, designed for distribution networks, secondary substations, renewable energy feed-in (wind, PV, BESS) and industrial and infrastructure projects, with an annual capacity of up to 2,500 transformers.
Does Rauscher & Stoecklin Poland also offer consulting and project support?
Yes. In addition to supplying transformers, Rauscher & Stoecklin Poland offers technical consulting and design, project support from specification to commissioning, and assistance with type selection, standards and grid requirements for grid operators, municipal utilities, EPCs and industrial customers.