Quality control management at charging pile factories is a closed-loop, full-lifecycle system covering design verification, incoming quality control (IQC), in-process quality control (IPQC), and final quality control/outgoing quality control (FQC/OQC)—including full inspection and burn-in testing.
Core Processes and Key Control Points
1. Design and R&D Verification: Conduct technical feasibility reviews (thermal management, high-voltage isolation, EMC pre-design); build prototypes to perform withstand voltage tests (≥2000V/1min), temperature rise tests (junction temperature ≤100°C), protocol compatibility tests (GB/T 27930/OCPP), and environmental reliability simulations (high/low temperature, vibration) to eliminate design defects prior to mass production.
2. Incoming Quality Control (IQC): Audit supplier qualifications for core components (power modules, IGBTs, metering chips); perform spot checks on electrical performance (insulation resistance ≥100MΩ), mechanical strength, and visual appearance for incoming materials; strictly prohibit non-conforming materials from entering inventory.
3. In-Process Quality Control (IPQC): Establish Key Control Points (KCPs), including SMT reflow profile verification, soldering temperatures (350–400°C), and high-voltage connector torque (10–15 N·m); implement a First Article Inspection (FAI) system requiring checks at the start of every shift or line change; utilize an MES system to monitor environmental temperature/humidity (20±2°C / 40–60%) and process pass rates in real-time.
4. Final/Outgoing Quality Control (FQC/OQC): Conduct 100% inspection (appearance, insulation, leakage current ≤0.5mA, output accuracy ±1–2%) and a 72-hour high-temperature, full-load burn-in test (simulating continuous operation under extreme conditions); perform sample testing for EMC (electromagnetic compatibility), salt spray corrosion resistance, and short-circuit/over-voltage protection functionality.
5. Certification and Continuous Improvement: Obtain ETL/FCC/CE/UKCA/TUV/CB/RCM…. certifications through third-party agencies (Intertek, TUV, SGS……); establish mechanisms for isolating non-conforming products and conducting root cause analysis (8D reports); collect post-sales failure data to drive design optimizations. Key Inspection Indicators and Standards
– Electrical Safety: Insulation resistance ≥50 MΩ (some require 100 MΩ); no breakdown during power-frequency withstand voltage testing; leakage current ≤0.5 mA; grounding continuity resistance ≤0.1 Ω.
– Environmental Adaptability: Outdoor equipment typically requires an IP54 or IP65 protection rating; operating temperature range of -20°C to +50°C (or wider); must pass salt spray testing (stricter requirements for coastal areas).
– Performance Indicators: Charging efficiency ≥94–95%; output voltage/current accuracy ±1–2%; charging response time ≤200 ms; 100% success rate for communication protocol handshaking.
– Reliability Testing: 72-hour continuous burn-in test without failure; mating cycle/durability test (charging guns typically require ≥10,000 cycles); high/low-temperature cycling test.
Management System Support
– Policies and Procedures: Establish a Quality Inspection Plan, a Non-conforming Product Handling Procedure, and Standard Operating Procedures (SOPs); clearly define quality responsibilities for each role.
– Equipment and Personnel: Production lines equipped with Automated Test Equipment (ATE), infrared thermometers, torque wrenches, etc.; operators must undergo skills training, hold relevant certifications, and pass periodic assessments.
– Traceability System: Utilize barcode/RFID technology to achieve end-to-end traceability from raw material batches to finished product serial numbers, ensuring precise recall of defective products.