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All replacements

Find replacement for LONGi LGi7-72HYD-640M

640 W HPBC solar panel with 144 cells. Voc 54.02 V · Isc 14.98 A · TcVoc -0.2%/°C.

Select the panel you want to replace

Show only panels with matching cell technology

Compatible Replacements

40 panels found · 3670 panels excluded

LONGi LGi7-72HYD-635M

635 W

HPBC
95Exact match
ParameterOriginalReplacementDeviation
Voc54.02 V53.92 V0.2%
Vmpp44.67 V44.57 V0.2%
Isc14.98 A14.89 A0.6%
Impp14.33 A14.25 A0.6%
TcVoc-0.2 %/°C-0.2 %/°C±0.000 %/°C
TcPmax-0.26 %/°C-0.26 %/°C±0.000 %/°C
LONGi LGi7-72HYD-645M

645 W

HPBC
95Exact match
ParameterOriginalReplacementDeviation
Voc54.02 V54.12 V0.2%
Vmpp44.67 V44.77 V0.2%
Isc14.98 A15.06 A0.5%
Impp14.33 A14.41 A0.6%
TcVoc-0.2 %/°C-0.2 %/°C±0.000 %/°C
TcPmax-0.26 %/°C-0.26 %/°C±0.000 %/°C
LONGi LGi7-72HVD-655M

655 W

HPBC
93Good match
ParameterOriginalReplacementDeviation
Voc54.02 V54 V0.0%
Vmpp44.67 V44.66 V0.0%
Isc14.98 A15.37 A2.6%
Impp14.33 A14.67 A2.4%
TcVoc-0.2 %/°C-0.2 %/°C±0.000 %/°C
TcPmax-0.26 %/°C-0.26 %/°C±0.000 %/°C
LONGi LR7-72HVH-655M

655 W

HPBC
93Good match
ParameterOriginalReplacementDeviation
Voc54.02 V54 V0.0%
Vmpp44.67 V44.66 V0.0%
Isc14.98 A15.37 A2.6%
Impp14.33 A14.67 A2.4%
TcVoc-0.2 %/°C-0.2 %/°C±0.000 %/°C
TcPmax-0.26 %/°C-0.26 %/°C±0.000 %/°C
LONGi LR7-72HVHF-655M

655 W

HPBC
93Good match
ParameterOriginalReplacementDeviation
Voc54.02 V54 V0.0%
Vmpp44.67 V44.66 V0.0%
Isc14.98 A15.37 A2.6%
Impp14.33 A14.67 A2.4%
TcVoc-0.2 %/°C-0.2 %/°C±0.000 %/°C
TcPmax-0.26 %/°C-0.26 %/°C±0.000 %/°C
LONGi LR7-72HVHF-650M

650 W

HPBC
91Good match
ParameterOriginalReplacementDeviation
Voc54.02 V53.9 V0.2%
Vmpp44.67 V44.56 V0.2%
Isc14.98 A15.29 A2.1%
Impp14.33 A14.59 A1.8%
TcVoc-0.2 %/°C-0.2 %/°C±0.000 %/°C
TcPmax-0.26 %/°C-0.26 %/°C±0.000 %/°C
LONGi LGi7-72HVD-650M

650 W

HPBC
91Good match
ParameterOriginalReplacementDeviation
Voc54.02 V53.9 V0.2%
Vmpp44.67 V44.56 V0.2%
Isc14.98 A15.29 A2.1%
Impp14.33 A14.59 A1.8%
TcVoc-0.2 %/°C-0.2 %/°C±0.000 %/°C
TcPmax-0.26 %/°C-0.26 %/°C±0.000 %/°C
LONGi LGi7-72HYD-650M

650 W

HPBC
91Good match
ParameterOriginalReplacementDeviation
Voc54.02 V54.22 V0.4%
Vmpp44.67 V44.87 V0.4%
Isc14.98 A15.14 A1.1%
Impp14.33 A14.49 A1.1%
TcVoc-0.2 %/°C-0.2 %/°C±0.000 %/°C
TcPmax-0.26 %/°C-0.26 %/°C±0.000 %/°C
LONGi LR7-72HVH-650M

650 W

HPBC
91Good match
ParameterOriginalReplacementDeviation
Voc54.02 V53.9 V0.2%
Vmpp44.67 V44.56 V0.2%
Isc14.98 A15.29 A2.1%
Impp14.33 A14.59 A1.8%
TcVoc-0.2 %/°C-0.2 %/°C±0.000 %/°C
TcPmax-0.26 %/°C-0.26 %/°C±0.000 %/°C
LONGi LGi7-72HYD-630M

630 W

HPBC
90Good match
ParameterOriginalReplacementDeviation
Voc54.02 V53.82 V0.4%
Vmpp44.67 V44.47 V0.4%
Isc14.98 A14.81 A1.1%
Impp14.33 A14.17 A1.1%
TcVoc-0.2 %/°C-0.2 %/°C±0.000 %/°C
TcPmax-0.26 %/°C-0.26 %/°C±0.000 %/°C
LONGi LR7-72HVHF-645M

645 W

HPBC
89Good match
ParameterOriginalReplacementDeviation
Voc54.02 V53.8 V0.4%
Vmpp44.67 V44.46 V0.5%
Isc14.98 A15.21 A1.5%
Impp14.33 A14.51 A1.3%
TcVoc-0.2 %/°C-0.2 %/°C±0.000 %/°C
TcPmax-0.26 %/°C-0.26 %/°C±0.000 %/°C
LONGi LR7-72HVH-660M

660 W

HPBC
89Good match
ParameterOriginalReplacementDeviation
Voc54.02 V54.1 V0.1%
Vmpp44.67 V44.76 V0.2%
Isc14.98 A15.45 A3.1%
Impp14.33 A14.75 A2.9%
TcVoc-0.2 %/°C-0.2 %/°C±0.000 %/°C
TcPmax-0.26 %/°C-0.26 %/°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

54.02 V

Vmpp

44.67 V

Isc

14.98 A

Impp

14.33 A

TcVoc

-0.2 %/°C

TcPmax

-0.26 %/°C

Pmax

640 W

Cells

144

Length

2376 mm

Width

1128 mm

Thickness

5 mm

Weight

31 kg

The LONGi LGi7-72HYD-640M 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
LGi7-72HYD-630M630 W53.82 V14.81 A
LGi7-72HYD-635M635 W53.92 V14.89 A
LGi7-72HYD-645M645 W54.12 V15.06 A
LGi7-72HYD-650M650 W54.22 V15.14 A
LGi7-72HYD-655M655 W54.32 V15.22 A
LGi7-72HYD-660M660 W54.42 V15.3 A

Frequently Asked Questions

What specs must match when replacing the LONGi LGi7-72HYD-640M?

The most critical specs to match are: cell count (must be exactly 144), Voc close to 54.02 V (within ±5%), and temperature coefficient TcVoc close to -0.2%/°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 LONGi LGi7-72HYD-640M?

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 LONGi LGi7-72HYD-640M.