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All replacements

Find replacement for GCL-NT12R/66GDF 645

645 W TOPCon solar panel with 132 cells. Voc 49.4 V · Isc 16.21 A · TcVoc -0.25%/°C.

Select the panel you want to replace

Show only panels with matching cell technology

Compatible Replacements

146 panels found · 4193 panels excluded

Astronergy CHSM66RNDGF-BH635

635 W

TOPCon
96Exact match
ParameterOriginalReplacementDeviation
Voc49.4 V49.42 V0.0%
Vmpp41.94 V41.86 V0.2%
Isc16.21 A16.35 A0.9%
Impp15.38 A15.17 A1.4%
TcVoc-0.25 %/°C-0.25 %/°C±0.000 %/°C
TcPmax-0.29 %/°C-0.29 %/°C±0.000 %/°C
Astronergy CHSM66RNDGF-BH630

630 W

TOPCon
95Exact match
ParameterOriginalReplacementDeviation
Voc49.4 V49.34 V0.1%
Vmpp41.94 V41.82 V0.3%
Isc16.21 A16.27 A0.4%
Impp15.38 A15.07 A2.0%
TcVoc-0.25 %/°C-0.25 %/°C±0.000 %/°C
TcPmax-0.29 %/°C-0.29 %/°C±0.000 %/°C
Astronergy CHSM66RNDGF-BH640

640 W

TOPCon
92Good match
ParameterOriginalReplacementDeviation
Voc49.4 V49.57 V0.3%
Vmpp41.94 V41.99 V0.1%
Isc16.21 A16.42 A1.3%
Impp15.38 A15.24 A0.9%
TcVoc-0.25 %/°C-0.25 %/°C±0.000 %/°C
TcPmax-0.29 %/°C-0.29 %/°C±0.000 %/°C
JA Solar JAM66D45-640/LB

640 W

TOPCon
91Good match
ParameterOriginalReplacementDeviation
Voc49.4 V49.39 V0.0%
Vmpp41.94 V41.2 V1.8%
Isc16.21 A16.24 A0.2%
Impp15.38 A15.54 A1.0%
TcVoc-0.25 %/°C-0.25 %/°C±0.000 %/°C
TcPmax-0.29 %/°C-0.29 %/°C±0.000 %/°C
GCL-NT12R/66GDF 640

640 W

TOPCon
91Good match
ParameterOriginalReplacementDeviation
Voc49.4 V49.15 V0.5%
Vmpp41.94 V41.72 V0.5%
Isc16.21 A16.17 A0.2%
Impp15.38 A15.34 A0.3%
TcVoc-0.25 %/°C-0.25 %/°C±0.000 %/°C
TcPmax-0.29 %/°C-0.29 %/°C±0.000 %/°C
Astronergy CHSM66RNDGF-BH625

625 W

TOPCon
90Good match
ParameterOriginalReplacementDeviation
Voc49.4 V49.19 V0.4%
Vmpp41.94 V41.69 V0.6%
Isc16.21 A16.19 A0.1%
Impp15.38 A14.99 A2.5%
TcVoc-0.25 %/°C-0.25 %/°C±0.000 %/°C
TcPmax-0.29 %/°C-0.29 %/°C±0.000 %/°C
DMEGC DM630G12RT-B66HSW

630 W

TOPCon
90Good match
ParameterOriginalReplacementDeviation
Voc49.4 V49.49 V0.2%
Vmpp41.94 V41.25 V1.6%
Isc16.21 A16.23 A0.1%
Impp15.38 A15.3 A0.5%
TcVoc-0.25 %/°C-0.25 %/°C±0.000 %/°C
TcPmax-0.29 %/°C-0.29 %/°C±0.000 %/°C
DMEGC GH630G12RT-B66HST

630 W

TOPCon
90Good match
ParameterOriginalReplacementDeviation
Voc49.4 V49.49 V0.2%
Vmpp41.94 V41.25 V1.6%
Isc16.21 A16.23 A0.1%
Impp15.38 A15.3 A0.5%
TcVoc-0.25 %/°C-0.25 %/°C±0.000 %/°C
TcPmax-0.29 %/°C-0.29 %/°C±0.000 %/°C
Risen RSM132-11-630BNDG

630 W

TOPCon
89Good match
ParameterOriginalReplacementDeviation
Voc49.4 V49.46 V0.1%
Vmpp41.94 V41.17 V1.8%
Isc16.21 A16.16 A0.3%
Impp15.38 A15.31 A0.5%
TcVoc-0.25 %/°C-0.25 %/°C±0.000 %/°C
TcPmax-0.29 %/°C-0.29 %/°C±0.000 %/°C
Suntech STP630S-H66-Nsh+

630 W

TOPCon
89Good match
ParameterOriginalReplacementDeviation
Voc49.4 V49.5 V0.2%
Vmpp41.94 V41.15 V1.9%
Isc16.21 A16.19 A0.1%
Impp15.38 A15.31 A0.5%
TcVoc-0.25 %/°C-0.25 %/°C±0.000 %/°C
TcPmax-0.29 %/°C-0.29 %/°C±0.000 %/°C
JinkoSolar JKM630N-66HL4M-BDX

630 W

TOPCon
88Good match
ParameterOriginalReplacementDeviation
Voc49.4 V49.48 V0.2%
Vmpp41.94 V41.02 V2.2%
Isc16.21 A16.2 A0.1%
Impp15.38 A15.36 A0.1%
TcVoc-0.25 %/°C-0.25 %/°C±0.000 %/°C
TcPmax-0.29 %/°C-0.29 %/°C±0.000 %/°C
JinkoSolar JKM630N-66HL4M-BDV-Z4

630 W

TOPCon
88Good match
ParameterOriginalReplacementDeviation
Voc49.4 V49.48 V0.2%
Vmpp41.94 V41.02 V2.2%
Isc16.21 A16.2 A0.1%
Impp15.38 A15.36 A0.1%
TcVoc-0.25 %/°C-0.25 %/°C±0.000 %/°C
TcPmax-0.29 %/°C-0.29 %/°C±0.000 %/°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

49.4 V

Vmpp

41.94 V

Isc

16.21 A

Impp

15.38 A

TcVoc

-0.25 %/°C

TcPmax

-0.29 %/°C

Pmax

645 W

Cells

132

Bifaciality

80%

Length

2382 mm

Width

1134 mm

Thickness

30 mm

Weight

32.5 kg

The GCL-NT12R/66GDF 645 is a 645 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-NT12R/66GDF 635635 W48.88 V16.13 A
GCL-NT12R/66GDF 640640 W49.15 V16.17 A

Frequently Asked Questions

What specs must match when replacing the GCL-NT12R/66GDF 645?

The most critical specs to match are: cell count (must be exactly 132), Voc close to 49.4 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-NT12R/66GDF 645?

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-NT12R/66GDF 645.