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All replacements

Find replacement for GCL-NT10/78GDF 640

640 W TOPCon solar panel with 156 cells. Voc 57.15 V · Isc 13.9 A · TcVoc -0.25%/°C.

Select the panel you want to replace

Show only panels with matching cell technology

Compatible Replacements

82 panels found · 4257 panels excluded

GCL-NT10/78GDF 645

645 W

TOPCon
94Good match
ParameterOriginalReplacementDeviation
Voc57.15 V57.3 V0.3%
Vmpp48.68 V48.87 V0.4%
Isc13.9 A13.95 A0.4%
Impp13.15 A13.2 A0.4%
TcVoc-0.25 %/°C-0.25 %/°C±0.000 %/°C
TcPmax-0.29 %/°C-0.29 %/°C±0.000 %/°C
GCL-NT10/78GDF 635

635 W

TOPCon
94Good match
ParameterOriginalReplacementDeviation
Voc57.15 V57 V0.3%
Vmpp48.68 V48.48 V0.4%
Isc13.9 A13.85 A0.4%
Impp13.15 A13.1 A0.4%
TcVoc-0.25 %/°C-0.25 %/°C±0.000 %/°C
TcPmax-0.29 %/°C-0.29 %/°C±0.000 %/°C
JinkoSolar JKM635N-78HL4-BDV

635 W

TOPCon
90Good match
ParameterOriginalReplacementDeviation
Voc57.15 V57.21 V0.1%
Vmpp48.68 V47.86 V1.7%
Isc13.9 A13.92 A0.1%
Impp13.15 A13.27 A0.9%
TcVoc-0.25 %/°C-0.25 %/°C±0.000 %/°C
TcPmax-0.29 %/°C-0.29 %/°C±0.000 %/°C
JinkoSolar JKM630N-78HL4-BDV

630 W

TOPCon
89Good match
ParameterOriginalReplacementDeviation
Voc57.15 V57.08 V0.1%
Vmpp48.68 V47.7 V2.0%
Isc13.9 A13.86 A0.3%
Impp13.15 A13.21 A0.5%
TcVoc-0.25 %/°C-0.25 %/°C±0.000 %/°C
TcPmax-0.29 %/°C-0.29 %/°C±0.000 %/°C
Perlight Solar PLM-635DH8N-156

635 W

TOPCon
89Good match
ParameterOriginalReplacementDeviation
Voc57.15 V57.2 V0.1%
Vmpp48.68 V48.05 V1.3%
Isc13.9 A13.82 A0.6%
Impp13.15 A13.22 A0.5%
TcVoc-0.25 %/°C-0.25 %/°C±0.000 %/°C
TcPmax-0.29 %/°C-0.3 %/°C±0.010 %/°C
JinkoSolar JKM640N-78HL4-BDV

640 W

TOPCon
88Good match
ParameterOriginalReplacementDeviation
Voc57.15 V57.34 V0.3%
Vmpp48.68 V48.02 V1.4%
Isc13.9 A13.98 A0.6%
Impp13.15 A13.33 A1.4%
TcVoc-0.25 %/°C-0.25 %/°C±0.000 %/°C
TcPmax-0.29 %/°C-0.29 %/°C±0.000 %/°C
GCL-NT10/78GDF 650

650 W

TOPCon
88Good match
ParameterOriginalReplacementDeviation
Voc57.15 V57.45 V0.5%
Vmpp48.68 V49.06 V0.8%
Isc13.9 A14 A0.7%
Impp13.15 A13.25 A0.8%
TcVoc-0.25 %/°C-0.25 %/°C±0.000 %/°C
TcPmax-0.29 %/°C-0.29 %/°C±0.000 %/°C
Perlight Solar PLM-640DH8N-156

640 W

TOPCon
87Good match
ParameterOriginalReplacementDeviation
Voc57.15 V57.4 V0.4%
Vmpp48.68 V48.22 V0.9%
Isc13.9 A13.86 A0.3%
Impp13.15 A13.28 A1.0%
TcVoc-0.25 %/°C-0.25 %/°C±0.000 %/°C
TcPmax-0.29 %/°C-0.3 %/°C±0.010 %/°C
Ulica Solar UL-625M-156ADGN

625 W

TOPCon
86Good match
ParameterOriginalReplacementDeviation
Voc57.15 V56.95 V0.3%
Vmpp48.68 V47.8 V1.8%
Isc13.9 A13.8 A0.7%
Impp13.15 A13.08 A0.5%
TcVoc-0.25 %/°C-0.25 %/°C±0.000 %/°C
TcPmax-0.29 %/°C-0.29 %/°C±0.000 %/°C
JinkoSolar JKM645N-78HL4-BDV

645 W

TOPCon
85Good match
ParameterOriginalReplacementDeviation
Voc57.15 V57.47 V0.6%
Vmpp48.68 V48.17 V1.0%
Isc13.9 A14.04 A1.0%
Impp13.15 A13.39 A1.8%
TcVoc-0.25 %/°C-0.25 %/°C±0.000 %/°C
TcPmax-0.29 %/°C-0.29 %/°C±0.000 %/°C
Perlight Solar PLM-630DH8N-156

630 W

TOPCon
85Good match
ParameterOriginalReplacementDeviation
Voc57.15 V57 V0.3%
Vmpp48.68 V47.88 V1.6%
Isc13.9 A13.78 A0.9%
Impp13.15 A13.16 A0.1%
TcVoc-0.25 %/°C-0.25 %/°C±0.000 %/°C
TcPmax-0.29 %/°C-0.3 %/°C±0.010 %/°C
Tongwei TWMND-78HD635

635 W

TOPCon
84Good match
ParameterOriginalReplacementDeviation
Voc57.15 V57.2 V0.1%
Vmpp48.68 V48.05 V1.3%
Isc13.9 A13.82 A0.6%
Impp13.15 A13.22 A0.5%
TcVoc-0.25 %/°C-0.24 %/°C±0.010 %/°C
TcPmax-0.29 %/°C-0.28 %/°C±0.010 %/°C

String Compatibility Calculator

Verify the replacement panel works with your inverter

Panel Matcher

Find all compatible panels for a specific inverter

Already have panels?

Find an inverter that fits your panel array with the right MPPT range and DC/AC ratio.

How the Algorithm Works

Learn how panels are scored and matched

Original Panel Specs

Voc

57.15 V

Vmpp

48.68 V

Isc

13.9 A

Impp

13.15 A

TcVoc

-0.25 %/°C

TcPmax

-0.29 %/°C

Pmax

640 W

Cells

156

Bifaciality

80%

Length

2465 mm

Width

1134 mm

Thickness

30 mm

Weight

33.6 kg

The GCL-NT10/78GDF 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.

Other models in this series

ModelPowerVocIsc
GCL-NT10/78GDF 625625 W56.22 V14.01 A
GCL-NT10/78GDF 635635 W57 V13.85 A
GCL-NT10/78GDF 645645 W57.3 V13.95 A
GCL-NT10/78GDF 650650 W57.45 V14 A

Frequently Asked Questions

What specs must match when replacing the GCL-NT10/78GDF 640?

The most critical specs to match are: cell count (must be exactly 156), Voc close to 57.15 V (within ±5%), and temperature coefficient TcVoc close to -0.25%/°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.

Can I use a higher wattage replacement for the GCL-NT10/78GDF 640?

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.

What happens if the replacement panel has different voltage specs?

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 GCL-NT10/78GDF 640.