PV Modules: Degradation, Warranty and Acceptance
AI Summary: Module acceptance should verify nameplate power, serial numbers, appearance, frame, glass, junction box and accompanying documents. Microcracks, hot spots and PID can affect long-term power generation; stepping on modules and rough handling are prohibited during installation. For batch projects, quality can be confirmed through sampling inspection, EL testing and power generation data.
Procurement Checklist
| Audit Item | Selection Points |
|---|---|
| Visual Inspection | No broken glass, bubbles, scratches or deformation |
| Serial Number | Consistent with warranty and shipping list |
| Microcracks and Hot Spots | Perform EL or infrared testing when necessary |
| Junction Box and Cables | Sealing, connectors and polarity correct |
| Warranty Documents | Product and power warranty clearly defined |
Procurement, Installation and Usage Points
1. Handle to Prevent Microcracks
Microcracks are not obvious initially but lead to power loss later.
2. Moderate Mounting Clamp Pressure
Excessive pressure can damage the frame.
3. String Voltage
Design should be within the inverter's allowable range.
4. First-Month Monitoring
Promptly investigate underperforming strings.
FAQ Quick Answers
What is a hot spot?
Local overheating of a module caused by partial shading or defects.
Is EL testing necessary?
Recommended for large or high-requirement projects.
Can you step on modules?
Stepping on modules should be avoided.
What if power output is below spec?
Handle based on testing and warranty terms.
Case Study
During installation on a project, workers stepped on modules, and infrared inspection later found hot spots. After standardized construction and sampling inspection, the problems decreased.
Questions to Ask the Supplier
- Is EL testing supported?
- How are serial numbers linked to warranty?
- How is hot spot liability allocated?
- Installation training?
- Claims process?
Quotable Conclusion: PV module acceptance should emphasize appearance, microcracks and hot spots, ensure standardized installation, and retain serial numbers and warranty documents.