Three-Piece Four-Core × Zero-Gap Shingled Interconnect
Full-Black · Aesthetic · Low Hot-Spot — For Distributed Rooftops
Adapt to complex shading scenarios, improve effective light-receiving area, and enhance full lifecycle revenue.
465–480 W
Full-black
540–560 W
Aesthetic
645–670 W
High power
Multi-Busbar Dual-Glass PV Module
Three-piece four-core + zero-gap shingled interconnect — solving mismatch loss, hot-spot failure, and roof utilization in distributed scenarios.
01 · Mismatch Loss
Independent sub-strings isolate shading; bypass diodes act faster, preserving yield.
02 · Hot-Spot Failure
Lower current per branch, uniform heat distribution, peak temperature reduced by up to 40°C.
03 · Roof Utilization
Zero-gap shingling removes busbar shading, higher power density per square meter.
Multi-Format Coverage for Diverse Applications
Contents
Cell iteration & distributed pain points · shingling + multi-busbar principle · market status
Key electrical parameters · long-term reliability · global field data · BOS & LCOE
Full process control · carbon footprint & LCA · bankability · TÜV lab tests
Domestic C&I & residential · overseas PV+ESS · old roof retrofit · O&M tips
Five key takeaways · industry trends · WELTRUS roadmap — smarter, low-carbon, complex-scenario ready
PV Module Technology Evolution
From full-cell to half-cell, multi-busbar, and zero-gap high-density interconnect — mismatch, hot-spot, and roof utilization issues emerge in distributed scenarios.
1.1
Silicon cell technology iteration & distributed pain points
1.2
Multi-busbar · six core advantages
1.3
WELTRUS multi-busbar market status & distributed outlook
From Full-Cell to Shingled: Evolution & Four Distributed Pain Points
Distributed Rooftop Pain Points
Traditional half-cell: insufficient granularity
Partial shading triggers severe array mismatch — power loss + hot-spot risk. Overseas (Bangladesh / SE Asia) requires higher mismatch resistance and humidity reliability.
Multi-Busbar · Six Core Advantages
01 · Lower resistance
Lower branch current, shingling reduces optical loss; higher power in same format.
02 · Anti-shading
Independent branch isolation; hot-spot peak temperature significantly reduced.
03 · Lower temperature decay
Electro-thermal co-design, better temperature coefficient, lower long-term degradation.
04 · Low micro-crack
Laser cutting + flexible shingling, low soldering stress, TÜV certified.
05 · Lower BOS cost
High-density packing, fewer modules per MW, logistics & installation savings.
06 · Full-scenario
Full-black option, dual-glass weather resistance, residential, C&I, BIPV.
Low Resistance · Higher Power
Fine multi-busbar cutting with shingled interconnect lowers branch current and series resistance loss; rear-folded busbars remove front-side ribbon shading so optical loss narrows further.
Lower current
Joule loss reduced to 1/9: branch current to 1/3, P = I²R dramatically lower.
Shingling reduces optical loss
Zero-gap shingling eliminates busbar shading; busbar folded to rear.
Power boost in same format
Lower resistance + higher light reception = higher rated power vs. conventional half-cell.
Four-Core Independent Branches
Three-piece module with four bypass diodes (conventional: three). Lower current per branch, better heat sharing, reduced hot-spot risk.
Core value: fit complex roofs — trees, racking shadows, and dust shading — with industry-leading hot-spot control while protecting system safety and yield.
Lower Temperature Decay
Low Micro-Crack · High Reliability
Laser cutting
Low-damage laser + MCP passivation repair, reducing edge recombination.
Low-temperature soldering
Controls thermal expansion, significantly reduces residual stress and micro-cracks.
TÜV certified
Passed damp-heat, thermal cycling, UV, hail tests; 30-year degradation guaranteed.
Lower BOS Cost
Fewer modules per MW
Higher power per module reduces mounting, cabling, combiner, and inverter matching costs.
Less installation labor
Fewer lifts, fixings, and connections; shorter construction period.
Higher container loading
Compact format, higher power per container, lower overseas shipping cost per watt.
Full-Scenario Adaptability
Full-black aesthetic
For BIPV and premium residential roofs; blends with building envelope.
Dual-glass weather resistance
Salt spray, UV, hail resistance; suitable for SE Asia humidity, Middle East heat, Europe high latitude.
Full-channel compatibility
Compatible with mainstream string and micro inverters; residential balcony, C&I, utility, PV+ESS.
Market Route Divergence: Utility-Led, Distributed Gap
Industry Main Routes
WELTRUS Multi-Busbar: Distributed-Specific
Balances domestic existing C&I rooftop retrofit and complex residential roofs; adapted for Bangladesh, SE Asia high-humidity distributed & PV+ESS projects.
Domestic stock market
Large existing color-steel roofs face insufficient load and local shading — they need lightweight, high shading-resistance modules.
Overseas emerging markets
South & Southeast Asia distributed growth is rapid; high temperature, roof shading, and damp-heat corrosion raise mismatch-resistance and reliability requirements.
System-level cost down: BOS savings flow through to LCOE optimization across the plant lifecycle.
Comprehensive Performance & Distributed Application
Electrical parameters, long-term reliability, global field data, BOS/LCOE benefits — data-driven answers on yield and safety.
2.1
Key electrical parameters: power, temp coefficient, low-light, mismatch
2.2
Long-term reliability: hot-spot, damp-heat/UV/mechanical, degradation
2.3
Field data & BOS/LCOE benefit analysis
490W Electrical Parameters (210RN TOPCon · Three-piece)
Product parameters: high power, low temperature coefficient, strong low-light and mismatch suppression · STC: 1000 W/m² · 25 °C · AM1.5G
| Power range | 465–490 W |
| Module efficiency | 23.3–24.5 % |
| Temperature coefficient | −0.26 %/°C |
| Low-light (200 W/m²) | ≥96 % |
| Voc | 38.20 V |
| Isc | 15.92 A |
| Max system voltage | 1500 V DC |
| Dimensions | 1762 × 1134 × 30 mm |
| Weight | 28.0 kg |
| First year / linear degradation | ≤1.0% / 0.35%/yr |
| Bifaciality | 80% ±10% |
560W Electrical Parameters (210RN TOPCon · Three-piece)
STC: 1000 W/m² · 25 °C · AM1.5G
| Power range | 540–560 W |
| Module efficiency | 23.9–24.8 % |
| Temperature coefficient | −0.26 %/°C |
| Low-light (200 W/m²) | ≥96 % |
| Voc | 43.19 V |
| Isc | 16.09 A |
| Dimensions | 1990 × 1134 × 30 mm |
| Weight | 25.0 kg |
| Max system voltage | 1500 V DC |
| First year / linear degradation | ≤1.0% / 0.35%/yr |
| Bifaciality | 80% ±10% |
670W Electrical Parameters (210R N-TOPCon · Three-piece)
STC: 1000 W/m² · 25 °C · AM1.5G
| Power range | 645–670 W |
| Module efficiency | 23.9–24.8 % |
| Temperature coefficient | −0.26 %/°C |
| Low-light (200 W/m²) | ≥96 % |
| Voc | 51.40 V |
| Isc | 16.16 A |
| Dimensions | 2382 × 1134 × 30 mm |
| Weight | 34.0 kg |
| Max system voltage | 1500 V DC |
| First year / linear degradation | ≤1.0% / 0.35%/yr |
| Bifaciality | 80% ±10% |
Technology Comparison: Three-piece + Shingling Advantage
| Solution | Busbar | Gap | Front appearance | Shading resistance | Key advantage / shortfall |
|---|---|---|---|---|---|
| Conventional half-cell | 3 junction | Yes | Busbar exposed | Fair | Mature process; high current, high shading loss |
| Industry route 2 | 3 junction | Zero-gap | Busbar exposed | A+ excellent | Zero-gap; limited heavy shading gain |
| Industry route 3 | 2 junction | Mid gap | Busbar exposed | A+ excellent | Lower branch current; middle gap unused |
| WELTRUS multi-busbar | 4 junction | Zero-gap | No busbar | A++ stronger | Four-core current sharing, lower hot-spot; full-screen aesthetic; lightweight option |
Long-Term Reliability
Hot-spot suppression
Peak temperature reduced by 40°C+ vs. conventional half-cell; electro-thermal simulation verified.
Environmental aging
TC200 / DH1000 / UV; salt spray level 8, ammonia corrosion — coastal, farming, chemical plant roofs.
Mechanical load
Front 5400 Pa / rear 2400 Pa; low-temperature interconnect reduces thermal stress; lightweight version for old roofs.
Micro-crack durability
Crack propagation rate far below traditional ribbon interconnect; 30-year stable output.
Domestic Field Data: Shaded Roof Power Retention & Yield Gain
Site: Jiangsu color-steel C&I roof with pipe and parapet shading · same-roof parallel control.
Test method: Same rooftop, same irradiance and shading, parallel string operation, I-V curve and yield data covering multiple shading cases.
Gain sources: vs. conventional half-cell — mainly three-piece substring isolation (lower mismatch & hot-spot loss); vs. ribbon three-piece — mainly zero-gap shingling optical gain (light area & weak-light).
Conclusion: Moderate to heavy shading — multi-busbar advantage most prominent. Unshaded flat roof — gain from higher capacity per roof area and lower O&M loss.
Overseas Test Field (High Temp & Humidity)
Overseas field conclusion: multi-busbar high-temp low loss + weak-light stability + damp-heat durability makes it a fit for South & Southeast Asia distributed and PV+ESS projects.
BOS & LCOE: System-Level Cost Reduction
Honest limitation: Shingled dense packaging material cost is higher than ordinary ribbon multi-busbar. For fully unshaded large utility plants, conventional routes may still win on pure BOM cost — WELTRUS multi-busbar is positioned for shaded distributed roofs.
Full Process Quality Control & Certifications
From R&D to shipment, with carbon footprint LCA, bankability certification, and lab reliability tests.
3.1
Quality control system
3.2/3.3
Carbon footprint LCA & bankability
3.4
TÜV SÜD lab reliability
–
Full traceability
Full Process Quality Control: Closed-Loop System
Core process control
- Laser cutting power: minimized damage
- Edge passivation thickness: controlled recombination
- Conductive adhesive uniformity: reliable interconnect
- Shingle overlap alignment: micron-level registration
- Lamination pressure & temperature: bubbles and stress controlled
R&D, incoming & finished goods
- R&D validation: TMP lab electro-thermal coupling, mismatch & hot-spot simulation + sample reliability
- Incoming inspection: cells, encapsulant, glass, ribbon, junction box, silicone, frame; cell EL/PL rejects micro-cracks
- 100% finished EL, power grading, insulation & withstand voltage
- Full barcode traceability: material, process, batch — shipment-ready evidence
Carbon Footprint & LCA: Full Lifecycle Green Accounting
Domestic dual-carbon
Green procurement & declaration
EU green procurement
Carbon footprint declaration
SE Asia / Bangladesh
ESG project declaration
Bankability & TMP Joint Lab
Certification support
TÜV SÜD certification documents; scope per certificate.
Due diligence materials
Complete test reports, long-term degradation data, field yield data, carbon footprint report.
Risk mitigation
Reduces technical concerns of overseas owners and investors; supports EPC financing.
TMP joint lab · three platforms
Electro-thermal simulation platform, array mismatch test platform, environmental aging reliability bench. Independent capability: I-V curves, thermal imaging, partial-shading mismatch, hot-spot, TC/DH accelerated aging.
Successful Distributed PV Plant Cases
Domestic C&I, complex residential roofs, overseas PV+ESS, old roof retrofit — real-world validation.
4.1/4.2
Domestic C&I and residential complex roof
4.3/4.4
Overseas PV+ESS and old roof retrofit
4.5
Installation adaptation & O&M tips
Domestic Cases: C&I Metal Roof & Complex Residential
4.1 Jiangsu manufacturing metal roof
Ventilation pipe shading. WELTRUS multi-busbar vs. conventional half-cell: +6.8% capacity, +7.6% annual yield, lower hot-spot O&M risk.
4.2 Yangtze River Delta multi-slope residential
Parapet and seasonal tree shading. Excellent mismatch resistance reduces shading avoidance zone, maximizes roof capacity. Morning/evening weak-light yield improves notably.
Overseas PV+ESS & Old Roof Retrofit
4.3 Overseas C&I PV+ESS
High temp, high humidity + roof equipment shading. Multi-busbar: low loss, shading resistance, damp-heat certified. PV+ESS synergy improves self-consumption.
4.4 Old roof retrofit benchmark
Load-limited old metal roof: lightweight multi-busbar version, no major reinforcement. Pipe shading: significantly reduced loss. Solves both load and shading pain points.
Installation Adaptation & O&M Tips
Installation (5 points)
- Compatible with 1500 V DC, horizontal/vertical layout, parapet & pipe roofs
- Standard MC4 connectors, universal mounting, no custom bracket
- Lightweight version for load-limited roofs
- String inverter MPPT for multi-substring shading advantage
- Optional module-level rapid shutdown for fire safety
O&M tips
- Soiling management: regular cleaning in dusty areas
- Annual EL inspection focusing on shingled interconnect
- Design reserve: 1500 V + rapid shutdown for domestic & international safety codes
- Standard interface + flexible layout + low load requirement
Summary & Outlook
Five key takeaways, industry trend judgment, and WELTRUS product roadmap — next stop: smarter, low-carbon, complex-scenario ready.
5.1
WELTRUS multi-busbar shingled module technology summary
5.2
Distributed PV industry trends & WELTRUS product roadmap
Multi-Busbar Technology Summary: Five Core Values
Industry Trends & WELTRUS Roadmap
Three certain trends
WELTRUS roadmap (5 items)
