Stringing
Station #9 · module side · ×6 parallel · 80s cycle
running
Availability
98.6%
Performance
96.2%
Quality
96.0%
WIP
0
823 processed · 26 rejected
Stringer — process map
Ribbon arch: MBB12 · tension 4.00 N · solder 240°C × 600 ms
Solder reflow profile
Liquidus (Sn-Pb 183°C) shown dashed
Time >183°C
125 msPeak ΔT
215.0°CCooling rate
44.0°C/sStringer — physics windows & sensitivities
Microcrack P vs cell thickness
P_crack = 1.50% · extent 4.5%
Solder ΔiVoc vs iron T
ΔiVoc = 5.60 mV
Joint & alignment
Peel strength2.300 N/mm
Alignment σ0.110 mm
Ribbon Rs4.000 mΩ
Crack-probability surface · tension × thickness
Process window outlined where P_crack ≤ 1%. Operating point shown with crosshair. Re-evaluates instantly with lever moves.
Sensitivity to crack rate
±1 step perturbation around current setpoint, propagated through stringer model.
Ribbon architecture comparison
| Arch | P_crack | ΔiVoc mV | Peel N/mm | R_ribbon mΩ | Notes |
|---|---|---|---|---|---|
| 5BB | 1.80% | 8.00 | 2.30 | 9.00 | Legacy, highest thermal load |
| 9BB | 1.80% | 6.80 | 2.30 | 6.00 | Tension-sensitive on thin |
| MBB12 ◀ | 1.50% | 5.60 | 2.30 | 4.00 | Multi-busbar, balanced |
| SmartWire18 | 0.75% | 0.00 | 2.00 | 2.50 | Cold bond, lowest Rs, gentlest |
Live microcrack telemetry · last 12 events
| t | Module | Cell # | Sev |
|---|---|---|---|
| 476.3 | mod_seed_ce | 56 | 0.50 |
| 461.3 | mod_seed_ca | 60 | 0.40 |
| 453.8 | mod_seed_c8 | 26 | 0.50 |
| 450.0 | mod_seed_c7 | 70 | 0.40 |
| 450.0 | mod_seed_c7 | 65 | 0.40 |
| 450.0 | mod_seed_c7 | 57 | 0.60 |
| 450.0 | mod_seed_c7 | 46 | 0.50 |
| 450.0 | mod_seed_c7 | 39 | 0.80 |
| 450.0 | mod_seed_c7 | 8 | 0.70 |
| 446.3 | mod_seed_c6 | 19 | 0.80 |
Yield projection & economics
Crack rate
1.500%
per cell, current setpoint
Module rework
0.89/hr
@ 60 mod/hr, 99.2% nom
Revenue at risk
$65/hr
scrap × $0.21/W × 580W × 60%
Architecture margin
75%
thermal headroom vs 5BB
SmartWire18 is thermally cold (no soldering iron) and mechanically gentlest. 5BB/9BB increase tension-induced crack risk on <130 µm cells. Process window for <1% cracks: tension ≤ 4.0 N at current thickness 130 µm.
Hero physics — live levers
Adjustments mutate the active recipe and propagate through the physics chain on the next tick. Changes are logged in the lever tracker.
Soldering iron T240 °C
range 180–280
Solder dwell600 ms
range 200–1500
String tension4.00 N
range 1–10
Cell thickness130 µm
range 120–180
Recent events
Lever-tracker filtered to this station:
| t | Param | Old → New |
|---|---|---|
| 346.9 | stringTensionN | 4 → 3.7 |
| 318.8 | solderTempC | 240 → 235 |
| 126.9 | ribbonArch | MBB12 → MBB12 |