640 W TOPCon solar panel with 120 cells. Voc 44.34 V · Isc 18.34 A · TcVoc -0.26%/°C.
Select the panel you want to replace
Voc
44.34 V
Vmpp
36.97 V
Isc
18.34 A
Impp
17.31 A
TcVoc
-0.26 %/°C
TcPmax
-0.3 %/°C
Pmax
640 W
Cells
120
Bifaciality
80%
The Waaree Energies BiN-02-640 is a 640 W solar panel. Finding a compatible replacement requires matching the original electrical characteristics — particularly Voc, Vmpp, Isc, and temperature coefficients — to ensure safe operation within the same string.
Use the form above to find panels that match these specifications. Then verify the replacement in the String Compatibility Calculator with your inverter.
| Model | Power | Voc | Isc |
|---|---|---|---|
| 615 W | 43.44 V | 18.13 A | |
| 620 W | 43.62 V | 18.17 A | |
| 625 W | 43.8 V | 18.22 A | |
| 630 W | 43.98 V | 18.26 A | |
| 635 W | 44.16 V | 18.3 A | |
| 645 W | 44.52 V | 18.38 A | |
| 650 W | 44.7 V | 18.42 A |
The most critical specs to match are: cell count (must be exactly 120), Voc close to 44.34 V (within ±5%), and temperature coefficient TcVoc close to -0.26%/°C. If Voc differs significantly, the string voltage at extreme temperatures may shift outside the inverter's MPPT range. The replacement finder above pre-screens all candidates by these criteria.
A higher wattage panel usually has a higher Vmpp or Isc, which can affect string voltage and current. Small increases (up to 10–15%) are typically safe if the other electrical specs align. The replacement finder shows a compatibility score — 'Exact match' means the specs align closely. Always verify the replacement in the String Compatibility Calculator with your inverter before installation.
If the replacement has a significantly different Voc or Vmpp, the string voltage may shift outside the inverter's MPPT range, reducing energy production or causing faults. This effect is amplified at temperature extremes: at low temperatures, voltage rises by the TcVoc coefficient. The replacement finder automatically accounts for this — it scores candidates by how closely the electrical specs match the original Waaree Energies BiN-02-640.