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All replacements

Find replacement for Tongwei TWMND-78HD645

645 W TOPCon solar panel with 156 cells. Voc 57.6 V · Isc 14.05 A · TcVoc -0.24%/°C.

Select the panel you want to replace

Show only panels with matching cell technology

Compatible Replacements

72 panels found · 4267 panels excluded

Tongwei TWMND-78HD640

640 W

TOPCon
92Good match
ParameterOriginalReplacementDeviation
Voc57.6 V57.4 V0.3%
Vmpp48.36 V48.22 V0.3%
Isc14.05 A13.86 A1.4%
Impp13.34 A13.28 A0.4%
TcVoc-0.24 %/°C-0.24 %/°C±0.000 %/°C
TcPmax-0.28 %/°C-0.28 %/°C±0.000 %/°C
JinkoSolar JKM650N-78HL4-BDV

650 W

TOPCon
91Good match
ParameterOriginalReplacementDeviation
Voc57.6 V57.6 V0.0%
Vmpp48.36 V48.33 V0.1%
Isc14.05 A14.1 A0.4%
Impp13.34 A13.45 A0.8%
TcVoc-0.24 %/°C-0.25 %/°C±0.010 %/°C
TcPmax-0.28 %/°C-0.29 %/°C±0.010 %/°C
Yingli Solar YL640CF78 e/2

640 W

TOPCon
91Good match
ParameterOriginalReplacementDeviation
Voc57.6 V57.62 V0.0%
Vmpp48.36 V47.73 V1.3%
Isc14.05 A14.05 A0.0%
Impp13.34 A13.41 A0.5%
TcVoc-0.24 %/°C-0.24 %/°C±0.000 %/°C
TcPmax-0.28 %/°C-0.29 %/°C±0.010 %/°C
JinkoSolar JKM645N-78HL4-BDV

645 W

TOPCon
88Good match
ParameterOriginalReplacementDeviation
Voc57.6 V57.47 V0.2%
Vmpp48.36 V48.17 V0.4%
Isc14.05 A14.04 A0.1%
Impp13.34 A13.39 A0.4%
TcVoc-0.24 %/°C-0.25 %/°C±0.010 %/°C
TcPmax-0.28 %/°C-0.29 %/°C±0.010 %/°C
Qcells Q.TRON XL-G2.3/BFG 635

635 W

TOPCon
88Good match
ParameterOriginalReplacementDeviation
Voc57.6 V57.51 V0.2%
Vmpp48.36 V48.09 V0.6%
Isc14.05 A13.93 A0.9%
Impp13.34 A13.21 A1.0%
TcVoc-0.24 %/°C-0.24 %/°C±0.000 %/°C
TcPmax-0.28 %/°C-0.3 %/°C±0.020 %/°C
Yingli Solar YL645CF78 e/2

645 W

TOPCon
87Good match
ParameterOriginalReplacementDeviation
Voc57.6 V57.82 V0.4%
Vmpp48.36 V47.89 V1.0%
Isc14.05 A14.1 A0.4%
Impp13.34 A13.47 A1.0%
TcVoc-0.24 %/°C-0.24 %/°C±0.000 %/°C
TcPmax-0.28 %/°C-0.29 %/°C±0.010 %/°C
Yingli Solar YL635CF78 e/2

635 W

TOPCon
86Good match
ParameterOriginalReplacementDeviation
Voc57.6 V57.42 V0.3%
Vmpp48.36 V47.57 V1.6%
Isc14.05 A14.01 A0.3%
Impp13.34 A13.35 A0.1%
TcVoc-0.24 %/°C-0.24 %/°C±0.000 %/°C
TcPmax-0.28 %/°C-0.29 %/°C±0.010 %/°C
Tongwei TWMND-78HD635

635 W

TOPCon
85Good match
ParameterOriginalReplacementDeviation
Voc57.6 V57.2 V0.7%
Vmpp48.36 V48.05 V0.6%
Isc14.05 A13.82 A1.6%
Impp13.34 A13.22 A0.9%
TcVoc-0.24 %/°C-0.24 %/°C±0.000 %/°C
TcPmax-0.28 %/°C-0.28 %/°C±0.000 %/°C
DMEGC DM635M10T-B78HSW

635 W

TOPCon
84Good match
ParameterOriginalReplacementDeviation
Voc57.6 V57.5 V0.2%
Vmpp48.36 V47.67 V1.4%
Isc14.05 A14.09 A0.3%
Impp13.34 A13.34 A0.0%
TcVoc-0.24 %/°C-0.25 %/°C±0.010 %/°C
TcPmax-0.28 %/°C-0.29 %/°C±0.010 %/°C
DMEGC DM640M10T-B78HSW

640 W

TOPCon
84Good match
ParameterOriginalReplacementDeviation
Voc57.6 V57.7 V0.2%
Vmpp48.36 V47.86 V1.0%
Isc14.05 A14.14 A0.6%
Impp13.34 A13.39 A0.4%
TcVoc-0.24 %/°C-0.25 %/°C±0.010 %/°C
TcPmax-0.28 %/°C-0.29 %/°C±0.010 %/°C
JinkoSolar JKM640N-78HL4-BDV

640 W

TOPCon
83Good match
ParameterOriginalReplacementDeviation
Voc57.6 V57.34 V0.5%
Vmpp48.36 V48.02 V0.7%
Isc14.05 A13.98 A0.5%
Impp13.34 A13.33 A0.1%
TcVoc-0.24 %/°C-0.25 %/°C±0.010 %/°C
TcPmax-0.28 %/°C-0.29 %/°C±0.010 %/°C
Yingli Solar YL650CF78 e/2

650 W

TOPCon
83Good match
ParameterOriginalReplacementDeviation
Voc57.6 V58.02 V0.7%
Vmpp48.36 V48.04 V0.7%
Isc14.05 A14.14 A0.6%
Impp13.34 A13.53 A1.4%
TcVoc-0.24 %/°C-0.24 %/°C±0.000 %/°C
TcPmax-0.28 %/°C-0.29 %/°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

57.6 V

Vmpp

48.36 V

Isc

14.05 A

Impp

13.34 A

TcVoc

-0.24 %/°C

TcPmax

-0.28 %/°C

Pmax

645 W

Cells

156

Bifaciality

80%

Length

2465 mm

Width

1134 mm

Thickness

30 mm

Weight

33.8 kg

The Tongwei TWMND-78HD645 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
TWMND-78HD625625 W56.8 V13.74 A
TWMND-78HD630630 W57 V13.78 A
TWMND-78HD635635 W57.2 V13.82 A
TWMND-78HD640640 W57.4 V13.86 A

Frequently Asked Questions

What specs must match when replacing the Tongwei TWMND-78HD645?

The most critical specs to match are: cell count (must be exactly 156), Voc close to 57.6 V (within ±5%), and temperature coefficient TcVoc close to -0.24%/°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 Tongwei TWMND-78HD645?

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 Tongwei TWMND-78HD645.