Incoming Component Inspection (IQC)

Every batch of IGBT modules, capacitors, PCBs, and connectors is inspected before entering production. We verify component authenticity, electrical parameters, and physical integrity. IGBT modules are sourced exclusively from Infineon, Mitsubishi, or Fuji — we never use unbranded alternatives. Incoming rejection rate target: <0.5%.

SMT Assembly & AOI Optical Inspection

Our in-house SMT (Surface Mount Technology) production line automatically places 200+ components per PCB with ±0.05mm precision. After soldering, every board passes through AOI (Automated Optical Inspection) — a high-resolution camera system that detects solder bridges, missing components, misalignment, and polarity errors. Defect detection accuracy: 99.7%.

Conformal Coating (Three-Proof Protection)

Every assembled PCB receives conformal coating — a protective polymer layer that shields circuits from moisture, dust, salt spray, and chemical corrosion. This is critical for VFDs deployed in harsh environments (mines, farms, coastal areas, chemical plants). Coating thickness: 25-75μm, verified by UV fluorescence inspection. Compliance: IPC-A-610 Class 2 standard.

Assembly & In-Process Quality Check (IPQC)

During assembly, technicians verify torque specifications on all terminal connections, check heatsink thermal compound application, and confirm wiring harness routing. Random sampling inspection occurs every 2 hours during production runs.

100% Full-Load Aging Test (Burn-In)

This is where we differ from most factories. Every single unit — not a sample — runs at full rated load for a minimum of 4 hours in a temperature-controlled aging room (40°C ambient). During burn-in, we monitor:

• Output voltage stability: ±1% of rated value
• Output current accuracy: within rated capacity
• Heatsink temperature: must stay within design limits
• Control panel functionality: all buttons, display, indicators
• Protection triggers: OC, OV, OH simulated and verified

Units that fail any parameter are rejected and root-caused. Pass rate target: >99.5%.

Final Inspection & Packaging (FQC/OQC)

Before packaging, each unit undergoes final visual inspection (cosmetics, labeling, accessory completeness) and functional verification. Export packaging includes: anti-static bag, foam padding, moisture barrier bag with desiccant, and wooden crate for units above 30kW. Every shipment includes a QC test report documenting the aging test results for that specific unit.