Plant engineers and maintenance teams rarely fail because they lack a budget for new equipment. They lose time—and production. When a critical, custom‑wound transformer in a legacy machine fails and the original manufacturer no longer exists, has acquired, or simply no longer supports the part. The result is a paper mill or a chemical processing line that sits idle, hemorrhaging revenue. While the procurement team searches desperately for a replacement that was custom‑built in 1987.
TPS Elektronik’s reverse engineering and rapid redesign service for transformer windings built for exactly this scenario. When a large paper mill faced a catastrophic failure of a custom gate‑drive transformer in a legacy drive system, TPS able to de‑construct the failed unit, reverse‑engineer its electrical and mechanical specifications, and manufacture a new, upgraded winding that fit the original footprint. All within a timeframe that minimized costly production downtime.
1. The challenge: catastrophic failure of an obsolete component
The mill’s critical drive system relied on a custom, multi‑winding isolation transformer, supplying power to sensitive gate‑drive circuits. After decades of thermal cycling, the insulation on the original windings had become brittle and eventually failed, causing a short circuit. The original equipment manufacturer had been acquired and the transformer was no longer available. A full drive retrofit quoted at 18 weeks and a significant capital expense. The mill needed a faster, more cost‑effective solution. This situation perfectly illustrates the value of an obsolete transformer winding replacement service that can replicate and even improve upon the original design.
2. The TPS reverse engineering solution
TPS proposed a two‑phase approach: rapidly reverse‑engineer the failed unit to create a precise manufacturing blueprint, then build a new, upgraded replacement winding using modern materials and automated winding processes for consistency. This approach is a core part of the EMS winding goods and coil winding service.
2.1 Failure analysis and deconstruction
TPS engineers began with a careful teardown, documenting wire gauge, turns count, winding configuration, inter‑layer insulation type, and core dimensions. This step is often the most delicate, as a damaged coil can easily lose its form. The data used to create a complete electrical and mechanical specification.
2.2 Rapid redesign and material upgrade
While the electrical specifications were preserved, TPS proposed a material upgrade. The original polyester insulation (Class F, 155 °C) was replaced with a modern polyimide insulation rated for Class H (180 °C), significantly improving the thermal margin and service life. TPS then manufactured the new winding using its automated multi‑axis CNC winding equipment. Which ensuring perfect layer alignment and consistent tension. This ability to handle diverse materials detailed in our guide to wire insulation materials, types, and applications. This approach ensured the upgraded replacement met all performance criteria of the original equipment.
2.3 Testing and documentation
Before shipment, the new winding underwent full electrical testing, including inductance, turns ratio, DC resistance, and a high‑potential (hipot) test at 125 % of the rated working voltage to ensure isolation integrity. A full test report provided, giving the mill’s engineering team the documentation needed for their internal safety audits.
3. Measurable results
The new, custom‑manufactured transformer winding was a drop‑in replacement for the original, fitting perfectly into the existing core and chassis. The entire process, from failure analysis to delivery of the replacement, completed in a fraction of the time quoted for a full drive retrofit. The production line restored to operation rapidly, saving the mill significant lost revenue. Furthermore, the upgraded insulation class ensures a longer operational life, providing a higher return on the repair investment. This success underscores the value of TPS’s broader production‑ready approach, as detailed in our resource on toroidal coils, dv/dt chokes, and production‑ready transformers.
4. RFQ checklist for legacy transformer restoration
- Original unit: The failed transformer, even if damaged, is critical for reverse engineering.
- Nameplate data: If available, provide input/output voltage, VA rating, and any other specifications.
- Application details: Describe the function of the transformer in the circuit (e.g., gate drive, isolation, flyback).
- Upgrade goals: Specify if a higher insulation class or other performance improvements are desired.
- Quantity: Initial replacement quantity and potential for future stock.
- Urgency: Required delivery date to minimize downtime.
5. FAQ
What if my failed transformer is physically destroyed and cannot be measured?
If a physical copy is unmeasurable, TPS engineers can often reverse‑engineer from the device’s schematic, the core geometry, and the remaining circuit parameters to reconstruct the winding specification.
Can TPS upgrade the insulation class of my legacy transformer?
Yes. TPS commonly upgrades legacy Class A or B insulations to modern Class F or H using high‑grade polyimide or other advanced materials, extending operational life.
Does TPS provide testing documentation for the new part?
Yes. A full electrical test report, including hipot, inductance, and resistance measurements, is provided, which is essential for safety audit compliance.
Where can I learn more about TPS’s broader winding capabilities?
Visit the TPS winding goods service page, or explore our technical guide on Helmholtz coil applications.
