Military and civil to exacting standards (including space) with full traceability. Wide variation in altitude/pressure, temperature and humidity. 400 Hz and switched mode supplies. Hermetically sealed, encapsulated, low outgassing for space applications etc.
Case Study: 400Hz Avionics Transformer
An international avionics company was seeking hermetically-sealed 400Hz isolation transformers to maintain older aircraft. The original design went back to the 1960s. A basic purchasing drawing existed, but no physical samples were available. The metal can and feedthrough connections needed to comply with MIL-T-27A.
The original design would likely have used a deep drawn metal can and lid, but tooling for this could not be justified for spares and refurbishment quantities. Accordingly the hardware was fabricated and plated by a company capable of finishing to the MIL standard. All units are leak tested after assembly to ensure performance at 70,000 ft.