Repair and rewinding of electric rotating machines
Repairing electric rotating machines has been a family tradition since 1936, and this expertise has remained our core business since Aselec was founded in 1992. From asynchronous and synchronous motors to high-voltage generators, we carry out complete overhauls of every type of rotating machine — from teardown to test-bench measurement.
The service life of electric motors and generators depends heavily on who rewinds and overhauls the windings, insulation and mechanical components, and with what technology. Our family has been repairing electric rotating machines for nearly nine decades, since 1936, and Aselec has carried that expertise forward since 1992 — from a few-kilowatt industrial asynchronous motors to multi-thousand-kilowatt medium- and high-voltage synchronous and DC machines. This experience, combined with our own winding, mechanical and test-bench departments in Szeged, allows us to carry out every step of motor repair — teardown, cleaning, measurement, winding, impregnation, assembly, test run — in one place, fully documented.
Repairing a rotating machine is not just about replacing a burnt winding: the root cause must be found, otherwise the overhauled machine will fail again shortly. That is why every incoming motor starts with a condition assessment — insulation resistance, winding resistance, air-gap measurement, bearing condition, and vibration diagnostics where needed. Based on the assessment we provide a quote and recommend the technology: rewinding with class F or H insulation materials, commutator replacement, rotor bar replacement, shaft replacement, or re-lamination — always tailored to the specific machine.
Rewound machines are vacuum-impregnated and then measured under load on our own test bench. The customer always receives a measurement report and repair documentation, which is important for future maintenance and warranty purposes. Repair of explosion-proof (Ex) motors is carried out as a certified repair workshop in accordance with MSZ EN IEC 60079-19:2020.
Why Aselec?
What we do
- Repair of AC and DC motors with no power limit
- Rewinding, re-lamination and bar replacement of stators and rotors
- Vacuum impregnation in class "F" and "H" insulation systems
- Insulation testing, dielectric strength measurement up to 25 kV
- Commutator repair and manufacturing, shaft replacement
- Vibration diagnostics, dynamic balancing
Typical applications
- →Industrial asynchronous motors, medium- and high-voltage motors
- →Synchronous and DC generators
- →Railway traction motors (Knorr-Bremse, Akiem projects), explosion-proof (Ex) motors
- →Special, custom-built rotating machines
How we work
- 1Condition assessmentTeardown, documentation, measurements and fault diagnosis.
- 2Mechanical and electrical repairWinding, lamination, machining, shaft replacement.
- 3ImpregnationVacuum impregnation in class F/H for long service life.
- 4Test-bench measurementElectrical and mechanical tests, balancing, report.
Frequently asked questions
What power range of motors do you repair?+
There is no upper power limit — we repair anything from a few-hundred-watt motor to multi-MW high-voltage machines.
Do you repair explosion-proof (Ex) motors?+
Yes, we are a certified repair workshop under MSZ EN IEC 60079-19:2020.
How long does it take to rewind an electric motor?+
It depends on the machine size and the severity of the fault. Rewinding a medium-sized asynchronous motor typically takes 1–3 weeks, but we can also arrange an expedited turnaround for urgent cases if agreed in advance.
Do you provide a warranty on the overhauled motor?+
Yes. We provide a written warranty and measurement report for every rotating machine we repair. The warranty period depends on the type of repair, typically 6–12 months under normal operating conditions.
Which is more cost-effective: buying a new motor or repairing the old one?+
For standard low-power asynchronous motors, buying new is often more economical. For medium-voltage, custom or long-lead-time machines, repair is almost always cheaper and faster — after an assessment we can provide a concrete cost comparison.