Manufacturer of custom transformers, chokes, power supplies and sine filters – Made in Germany since 1961.
Transformatoren Technik Jahnsmüller GmbH
71404 KorbNew on Amplifa
About Jahnsmüller
Transformatoren Technik Jahnsmüller GmbH is a mid-sized family company based in Korb near Stuttgart that has been developing and producing transformers, chokes, power supplies and sine filters since 1961. The portfolio includes single- and three-phase isolation, control, autotransformer and tapped transformers up to 230 kVA, smoothing, commutation, motor and line chokes up to 170 A, power supplies with 24 V DC output, and custom sine filters. As a manufacturer of wound components, production is carried out in-house with proprietary winding know-how; all products can be equipped with a UL-certified Class 155(F) insulation system. Customers come from ventilation and air-conditioning technology, the automotive industry, plant and mechanical engineering, as well as the US and Canadian markets (UL/CSA approvals). In addition to standard products, the company offers project planning, custom development, a 24-hour rush manufacturing service up to 15 kVA and its own express logistics. Development and production take place exclusively in Germany.
- Site
- Korb
- Processes
- Transformer winding and manufacturing (single-phase and three-phase,, Choke manufacturing (smoothing choke, commutation choke, motor choke, line choke,, Power supply manufacturing (single-phase and three-phase, 24V DC output), Sine filter manufacturing (three-phase, custom frequencies, voltages, clock frequencies), Project planning, design and custom development of wound components, Rewinding and repair of electric motors and magnetic components (historical), Rush manufacturing and express delivery (24-hour service up to 15 kVA), Project planning and execution
- Materials
- Copper (winding wire/coils), UL insulation materials Class 155(F) (insulation system, File-No. E251544), Copper (winding wire, stranded wire, flat wire), UL insulation materials insulation system Class 155(F), Transformer laminations (core stacks)
- Certificates
- ISO 9001:2015, UL/CSA Recognized Component (UL 5085, transformers), UL/CSA Recognized Component (UL 506, three-phase line chokes), UL insulation system Class 155(F), UL Recognized Component (UL 5085, UL 506), VDA 6.3 customer audit, SPE-1000 (Canada)
- Founded
- 1961
- Industries
- Ventilation and air-conditioning technology, Automotive, Plant engineering/Mechanical engineering, US and Canadian market (UL/CSA), Automotive (VDA 6.3 process audit for series products)
- 01
Project planning and custom development
- 02
Winding production (coil winding)
- 03
Assembly of wound components
- 04
Testing and certification (VDE, UL/CSA)
- 05
Delivery with own TJ logistics / express delivery
- 06
Service, on-site analysis and emergency service
Materials & Insulation Systems
Copper (winding wire, stranded wire, flat wire)
Base material of all windings and coils of transformers, chokes, power supplies and sine filters.
UL insulation materials insulation system Class 155(F)
UL-certified insulation system (File-No. E251544) for wound components, approved for winding temperatures up to 145 °C long-term at the hottest spot.
Transformer laminations (core stacks)
Used as magnetic core for isolation, control, autotransformer and tapped transformers.
Locations
Korb
DEHeadquarters, production and administration
- Part weight / size
- Transformers up to 230 kVA
- Lot size
- Single-unit and series production, stock items for standard products
- Materials
- Copper windings, Class 155(F) insulation materials
- Overhead cranes with increased load capacity (renewed in 2018)
- Winding machines (partly in-house built) for different wire gauges
Products & Components
Inside the production
Industries
Processes & technical limits
| Processes | Tolerance | Max. part | Weight | Lot size | Materials |
|---|---|---|---|---|---|
| Transformer winding and manufacturing (single-phase and three-phase,Assembly | – | – | up to 230 kVA (three-phase isolation | – | Copper, Class 155(F) insulation materials |
| Choke manufacturing (smoothing choke, commutation choke, motor choke, line choke,Assembly | – | – | three-phase line choke up to 170A | – | Copper |
| Power supply manufacturing (single-phase and three-phase, 24V DC output)Assembly | – | – | – | – | Copper |
| Sine filter manufacturing (three-phase, custom frequencies, voltages, clock frequencies)Assembly | – | – | – | – | Copper |
| Project planning, design and custom development of wound componentsEngineering | – | – | – | – | – |
| Rewinding and repair of electric motors and magnetic components (historical)Assembly | – | – | – | – | Copper |
| Rush manufacturing and express delivery (24-hour service up to 15 kVA)Assembly | – | – | 15 kVA | – | – |
3 Anlagen & Maschinen
| Machine | Manufacturer / model | Quantity | Working area | Year built | Site |
|---|---|---|---|---|---|
| Overhead crane | – | – | – | 2018 (erne | Korb |
| Winding machine | In-house built | – | – | – | – |
| Winding machines for different wire gauges | – | – | – | 1970er | Fellbach |
Additional services
Quality & Certifications
The manufacturing, operational and management processes are regularly certified according to ISO 9001:2015; successfully passed customer audits according to VDA 6.3 and SPE-1000 confirm the process quality. UL/CSA approvals as Recognized Component (UL 5085, UL 506) as well as a UL insulation system Class 155(F) complete the testing spectrum.
| Evidence | Korb |
|---|---|
| ISO 9001:2015 | |
| UL Recognized Component (UL 5085, UL 506) | |
| UL insulation system Class 155(F) | |
| VDA 6.3 customer audit | |
| SPE-1000 (Canada) |
Company History
- 1961
Werner Jahnsmüller takes over the repair workshop 'Rolf Schwab, Ing. Elektro-Apparatebau' in Stuttgart
- 1963
Company registered as 'Werner Jahnsmüller Elektro-Apparatebau'; licence to manufacture barn fans
- Mitte 1960er
Start of development and production of transformers; in-house built winding machine
- 1971
Relocation to Fellbach; eight employees
- 1981
Relocation to the new company site in Korb
- 1997
Werner Jahnsmüller hands over management to his daughter Katja and her husband Jörg Mast
- 2000er
Focus on custom transformers, chokes, power supplies and sine filters
- 2011
50th company anniversary
- 2018
New overhead cranes with increased load capacity simplify the production of heavy transformers
- 2020
Conversion of the production hall
- 2025
New size: three-phase isolation transformers up to 230 kVA