Visual Acceptance Criteria for Solar Panels Final Module Assembly. Jasbir Bath

Transcription

1 Visual Acceptance Criteria for Solar Panels Final Module Assembly Jasbir Bath Christopher Associates

2 Table of Contents 1. Scope and Classification 2. Applicable Documents 3. Requirements 4. Examples of Shipment of Modules 5. Notes 6. Appendix

3 Scope Develop visual acceptance standards for the solar panel in final module assembly. Included are junction boxes and other attributes For the junction boxes used in solar panels this would include: Inspection criteria for sealants and potting compounds used in the attachment. Sealants and potting compounds could have cracking and moisture ingress so a visual inspection quality system needed to determine acceptability.

4 3. Requirements Section Cells/ Strings/ Ribbon 3.2. Frame Glass 3.4. Junction Box 3.5. Mounting Hardware 3.6. Module 3.7 Electrical Test after Final Visual Inspection Serial lnumber and Identification i Lbl Label

5 3.1. Cells / Strings / Ribbon Cells: Breakage, chips, dents, deformation, shape, consistency, spacing, coloring Provide example pictures and/or acceptance criteria i for this What are the target conditions: what is a reject, what is acceptable, what is a near pass.

6 Example Cell Images Polysilicon Defect: Courtesy UC Santa Cruz.

7 Example Electrolumenesce Cell Images Left: Commercial 36 cell solar panel imaged Right: Close-up view of two cells with defects visible in the image on the left, revealing a semi-circular crack in the lower cell, dead sections, and a scatter of defects in the upper cell. Courtesy: Goodrich ISR Systems

8 Cell Images (Electrolumenesce) An emerging test method but if there is a crack seen by this technique what is the effect on efficiency of the cell. Feedback: The effect of a crack would be hard to predict. Electroluminescence imaging shows whether a crack is effecting output, even if it is just for the crack dimensions or for areas beyond the crack. Can detect whether the collector lines were cut by the curved crack and that sections are dead as a result.

9 Electrolumenesce Cell Image Feedback Can also detect dead areas due to material problems. In terms of total impact on cell production, software could quantify the dead area to estimate the % of dead to active area. Goodrich (Imaging equipment supplier) could conduct some testing of panels if needed.

10 3.1. Cells / Strings / Ribbon Strings: String Alignment, Camber, Straightness, spacing Ribbon: Alignment on Cell Provide example pictures and/or acceptance criteria for this

11 3.1. Cells / Strings / Ribbon Bus Bar: Alignment and Insulation Solder Joints Provide example pictures and/or acceptance criteria for this

12 3.1. Cells / Strings / Ribbon Lamination: Trapped Air or Volatiles (Bubbles) [Size, Quantity, Location] Provide example pictures and/or acceptance criteria i for this Reference lamination standard committee work in terms of acceptance criteria which will input into final module inspection criteria

13 3.2. Frame Square: sides to edges Level of squareness is needed. dd Joining of corners Corner Edge Roughness Provide example pictures and/or acceptance criteria for this

14 Scratches, dents 3.2. Frame Color uniformity it IPC to provide information from box build/ enclosurestandard standard (surface finish, color, uniformity, cosmetics, Class I and II anodization coating thickness) Tape or sealant used for joining. Used over glass. Provide example pictures and/or acceptance Provide example pictures and/or acceptance criteria for this

15 3.3 Glass Uniformity and consistency of glass Scratches, discoloration, cleanliness Chips, cracks/breakage (edges or center), dents or pits Provide example pictures and/or acceptance criteria for this. Will not include UV or Electroluminescence test criteria in this Section as this is typical done before final module visual inspection.

16 3.3 Glass Color uniformity (Shade) Textured side up or down Provide example pictures and/or acceptance criteria for this

17 3.4 Junction Box Two methods of attachment of junction boxes: Double sided tape or potting/sealing compound Tape: alignment uniform and compressed Potting / sealing compound: insufficient, excess, voids/gaps, uniform, cracking. Moisture ingress could be result of improper sealing. Provide example pictures and/or acceptance criteria for this.

18 3.4 Junction Box Wiring / Cable: length, insulation integrity, all installed and secure Standard d to use: IPC 620 standard d(cable wire hardness standard could be used as a reference). Rf Refer to drawing instructions ti for this. Connectors: male/female location, amount of torque Refer to drawing instructions. Provide example pictures and/or acceptance Provide example pictures and/or acceptance criteria for this

19 3.5 Mounting Hardware Mounting holes: size, qty and location Are there burrs on the holes. Are the holes egg shaped or bird holes. Refer to drawing instructions. Hardware Qty and type according to drawing Provide example pictures and/or acceptance criteria i for this.

20 3.6 Module Warpage Could still be evident when putting the module into the frame. Contamination Fingerprints, Hair, Solder Splash, Stains Thickness/ tolerances (edges/corners) Provide example pictures and/or acceptance criteria Provide example pictures and/or acceptance criteria for this

21 3.6 Module Backside bus bar exit excess or insufficient encapsulation material Excess encapsulation material on edges of solar module Contamination of front side glass (trimming of edges needed or not) Provide example pictures and/or acceptance Provide example pictures and/or acceptance criteria for this

22 3.7 Electrical Test after Final Visual Inspection Standards to refer to for types of electrical testing to conduct after final module visual inspection: IEC (Performance Requirements for Solar Simulators). A,B and C classifications in this test. Most tests to Class A. AM 1.5.

23 3.8 Serial Number and Identification Label Approved format per UL, IEC Indicate specific standards Location and alignment Legibility Clarity and permanency of marking. IPC to provide IPC standards d on lbli labeling to review and input into this. Unique serial number ID Datecode of manufacture

24 4. Examples of Shipment of Modules Different types of packing for shipment of modules after final visual linspection: i from simple stacking to cardboard spacers to dividers between modules. Need a minimum set of requirements for cost effective but defect free and safe shipment of modules. Provide example pictures for this.

25 Appendix Report form for Cells/Strings/Ribbon Report form for Frame Report form for Glass Report form for Junction Box Report form for Mounting Hardware Report Form for Module Report for Serial Number and Identification Label

26 Action Items Examples images and acceptance/ reject criteria are required for most of the sections. Cells/ Strings/ Ribbon Frame Glass Junction Box Mounting Hardware Module Module Shipment Action: All

27 Other considerations Common acceptance criteria developed in this Common acceptance criteria developed in this specification with other groups

28 Any other areas Next Steps