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All replacements

Find replacement for Maysun Solar MS640MTDG-66HR

640 W TOPCon solar panel with 132 cells. Voc 49.46 V · Isc 16.19 A · TcVoc -0.22%/°C.

Select the panel you want to replace

Show only panels with matching cell technology

Compatible Replacements

30 panels found · 3680 panels excluded

Maysun Solar MS630MTDG-66HR

630 W

TOPCon
92Good match
ParameterOriginalReplacementDeviation
Voc49.46 V49.27 V0.4%
Vmpp41.15 V40.98 V0.4%
Isc16.19 A16.11 A0.5%
Impp15.56 A15.38 A1.2%
TcVoc-0.22 %/°C-0.22 %/°C±0.000 %/°C
TcPmax-0.24 %/°C-0.24 %/°C±0.000 %/°C
Maysun Solar MS650MTDG-66HR

650 W

TOPCon
92Good match
ParameterOriginalReplacementDeviation
Voc49.46 V49.65 V0.4%
Vmpp41.15 V41.32 V0.4%
Isc16.19 A16.27 A0.5%
Impp15.56 A15.73 A1.1%
TcVoc-0.22 %/°C-0.22 %/°C±0.000 %/°C
TcPmax-0.24 %/°C-0.24 %/°C±0.000 %/°C
Maysun Solar MS620MTDG-66HR

620 W

TOPCon
83Good match
ParameterOriginalReplacementDeviation
Voc49.46 V49.08 V0.8%
Vmpp41.15 V40.81 V0.8%
Isc16.19 A16.04 A0.9%
Impp15.56 A15.2 A2.3%
TcVoc-0.22 %/°C-0.22 %/°C±0.000 %/°C
TcPmax-0.24 %/°C-0.24 %/°C±0.000 %/°C
Trina Solar TSM-NE19R.70-620

620 W

TOPCon
66Acceptable
ParameterOriginalReplacementDeviation
Voc49.46 V49.6 V0.3%
Vmpp41.15 V41.4 V0.6%
Isc16.19 A15.91 A1.7%
Impp15.56 A14.99 A3.7%
TcVoc-0.22 %/°C-0.24 %/°C±0.020 %/°C
TcPmax-0.24 %/°C-0.29 %/°C±0.050 %/°C
TommaTech TT630-132TNB12R G2G

630 W

TOPCon
66Acceptable
ParameterOriginalReplacementDeviation
Voc49.46 V49.39 V0.1%
Vmpp41.15 V41.42 V0.7%
Isc16.19 A16.14 A0.3%
Impp15.56 A15.22 A2.2%
TcVoc-0.22 %/°C-0.26 %/°C±0.040 %/°C
TcPmax-0.24 %/°C-0.3 %/°C±0.060 %/°C
Trina Solar TSM-NEG19R.20-620

620 W

TOPCon
66Acceptable
ParameterOriginalReplacementDeviation
Voc49.46 V49.6 V0.3%
Vmpp41.15 V41.4 V0.6%
Isc16.19 A15.91 A1.7%
Impp15.56 A14.99 A3.7%
TcVoc-0.22 %/°C-0.24 %/°C±0.020 %/°C
TcPmax-0.24 %/°C-0.29 %/°C±0.050 %/°C
TommaTech TT630-132TNB12R

630 W

TOPCon
66Acceptable
ParameterOriginalReplacementDeviation
Voc49.46 V49.39 V0.1%
Vmpp41.15 V41.42 V0.7%
Isc16.19 A16.14 A0.3%
Impp15.56 A15.22 A2.2%
TcVoc-0.22 %/°C-0.26 %/°C±0.040 %/°C
TcPmax-0.24 %/°C-0.3 %/°C±0.060 %/°C
Trina Solar TSM-NE19R-620

620 W

TOPCon
66Acceptable
ParameterOriginalReplacementDeviation
Voc49.46 V49.6 V0.3%
Vmpp41.15 V41.4 V0.6%
Isc16.19 A15.91 A1.7%
Impp15.56 A14.99 A3.7%
TcVoc-0.22 %/°C-0.24 %/°C±0.020 %/°C
TcPmax-0.24 %/°C-0.29 %/°C±0.050 %/°C
TommaTech TT635-132TNB12R G2G

635 W

TOPCon
63Acceptable
ParameterOriginalReplacementDeviation
Voc49.46 V49.59 V0.3%
Vmpp41.15 V41.62 V1.1%
Isc16.19 A16.2 A0.1%
Impp15.56 A15.26 A1.9%
TcVoc-0.22 %/°C-0.26 %/°C±0.040 %/°C
TcPmax-0.24 %/°C-0.3 %/°C±0.060 %/°C
TommaTech TT635-132TNB12R

635 W

TOPCon
63Acceptable
ParameterOriginalReplacementDeviation
Voc49.46 V49.59 V0.3%
Vmpp41.15 V41.62 V1.1%
Isc16.19 A16.2 A0.1%
Impp15.56 A15.26 A1.9%
TcVoc-0.22 %/°C-0.26 %/°C±0.040 %/°C
TcPmax-0.24 %/°C-0.3 %/°C±0.060 %/°C
TommaTech TT625-132TNB12R G2G

625 W

TOPCon
62Acceptable
ParameterOriginalReplacementDeviation
Voc49.46 V49.19 V0.5%
Vmpp41.15 V41.22 V0.2%
Isc16.19 A16.08 A0.7%
Impp15.56 A15.17 A2.5%
TcVoc-0.22 %/°C-0.26 %/°C±0.040 %/°C
TcPmax-0.24 %/°C-0.3 %/°C±0.060 %/°C
TommaTech TT625-132TNB12R

625 W

TOPCon
62Acceptable
ParameterOriginalReplacementDeviation
Voc49.46 V49.19 V0.5%
Vmpp41.15 V41.22 V0.2%
Isc16.19 A16.08 A0.7%
Impp15.56 A15.17 A2.5%
TcVoc-0.22 %/°C-0.26 %/°C±0.040 %/°C
TcPmax-0.24 %/°C-0.3 %/°C±0.060 %/°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

49.46 V

Vmpp

41.15 V

Isc

16.19 A

Impp

15.56 A

TcVoc

-0.22 %/°C

TcPmax

-0.24 %/°C

Pmax

640 W

Cells

132

Length

2382 mm

Width

1134 mm

Thickness

30 mm

Weight

35.6 kg

The Maysun Solar MS640MTDG-66HR 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
MS600MTDG-66HR600 W48.29 V15.8 A
MS605MTDG-66HR605 W48.49 V15.86 A
MS610MTDG-66HR610 W48.69 V15.92 A
MS615MTDG-66HR615 W48.89 V15.98 A
MS620MTDG-66HR620 W49.08 V16.04 A
MS630MTDG-66HR630 W49.27 V16.11 A
MS650MTDG-66HR650 W49.65 V16.27 A

Frequently Asked Questions

What specs must match when replacing the Maysun Solar MS640MTDG-66HR?

The most critical specs to match are: cell count (must be exactly 132), Voc close to 49.46 V (within ±5%), and temperature coefficient TcVoc close to -0.22%/°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 Maysun Solar MS640MTDG-66HR?

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 Maysun Solar MS640MTDG-66HR.