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All replacements

Find replacement for LONGi LR8-66HYD-645M

645 W HPBC solar panel with 132 cells. Voc 49.62 V · Isc 16.46 A · TcVoc -0.2%/°C.

Select the panel you want to replace

Show only panels with matching cell technology

Compatible Replacements

87 panels found · 4252 panels excluded

LONGi LR8-66HVDF-645M

645 W

HPBC
100Exact match
ParameterOriginalReplacementDeviation
Voc49.62 V49.62 V0.0%
Vmpp40.88 V40.88 V0.0%
Isc16.46 A16.46 A0.0%
Impp15.78 A15.78 A0.0%
TcVoc-0.2 %/°C-0.2 %/°C±0.000 %/°C
TcPmax-0.26 %/°C-0.26 %/°C±0.000 %/°C
LONGi LR8-66HVD-645M

645 W

HPBC
100Exact match
ParameterOriginalReplacementDeviation
Voc49.62 V49.62 V0.0%
Vmpp40.88 V40.88 V0.0%
Isc16.46 A16.46 A0.0%
Impp15.78 A15.78 A0.0%
TcVoc-0.2 %/°C-0.2 %/°C±0.000 %/°C
TcPmax-0.26 %/°C-0.26 %/°C±0.000 %/°C
LONGi LR8-66HVD-640M

640 W

HPBC
95Exact match
ParameterOriginalReplacementDeviation
Voc49.62 V49.52 V0.2%
Vmpp40.88 V40.78 V0.2%
Isc16.46 A16.38 A0.5%
Impp15.78 A15.69 A0.6%
TcVoc-0.2 %/°C-0.2 %/°C±0.000 %/°C
TcPmax-0.26 %/°C-0.26 %/°C±0.000 %/°C
Luxor Solar LX-645M/182R-132+ GG SW PRIME

645 W

TOPCon
95Exact match
ParameterOriginalReplacementDeviation
Voc49.62 V49.52 V0.2%
Vmpp40.88 V40.9 V0.0%
Isc16.46 A16.44 A0.1%
Impp15.78 A15.78 A0.0%
TcVoc-0.2 %/°C-0.2 %/°C±0.000 %/°C
TcPmax-0.26 %/°C-0.27 %/°C±0.010 %/°C
LONGi LR8-66HVDF-650M

650 W

HPBC
95Exact match
ParameterOriginalReplacementDeviation
Voc49.62 V49.72 V0.2%
Vmpp40.88 V40.98 V0.2%
Isc16.46 A16.54 A0.5%
Impp15.78 A15.86 A0.5%
TcVoc-0.2 %/°C-0.2 %/°C±0.000 %/°C
TcPmax-0.26 %/°C-0.26 %/°C±0.000 %/°C
LONGi LR8-66HVDF-640M

640 W

HPBC
95Exact match
ParameterOriginalReplacementDeviation
Voc49.62 V49.52 V0.2%
Vmpp40.88 V40.78 V0.2%
Isc16.46 A16.38 A0.5%
Impp15.78 A15.69 A0.6%
TcVoc-0.2 %/°C-0.2 %/°C±0.000 %/°C
TcPmax-0.26 %/°C-0.26 %/°C±0.000 %/°C
LONGi LR8-66HYD-640M

640 W

HPBC
95Exact match
ParameterOriginalReplacementDeviation
Voc49.62 V49.52 V0.2%
Vmpp40.88 V40.78 V0.2%
Isc16.46 A16.38 A0.5%
Impp15.78 A15.69 A0.6%
TcVoc-0.2 %/°C-0.2 %/°C±0.000 %/°C
TcPmax-0.26 %/°C-0.26 %/°C±0.000 %/°C
LONGi LR8-66HYD-650M

650 W

HPBC
95Exact match
ParameterOriginalReplacementDeviation
Voc49.62 V49.72 V0.2%
Vmpp40.88 V40.98 V0.2%
Isc16.46 A16.54 A0.5%
Impp15.78 A15.86 A0.5%
TcVoc-0.2 %/°C-0.2 %/°C±0.000 %/°C
TcPmax-0.26 %/°C-0.26 %/°C±0.000 %/°C
LONGi LR8-66HVD-650M

650 W

HPBC
95Exact match
ParameterOriginalReplacementDeviation
Voc49.62 V49.72 V0.2%
Vmpp40.88 V40.98 V0.2%
Isc16.46 A16.54 A0.5%
Impp15.78 A15.86 A0.5%
TcVoc-0.2 %/°C-0.2 %/°C±0.000 %/°C
TcPmax-0.26 %/°C-0.26 %/°C±0.000 %/°C
RECOM RCM-650-8DBRCM

650 W

IBC
94Good match
ParameterOriginalReplacementDeviation
Voc49.62 V49.54 V0.2%
Vmpp40.88 V40.83 V0.1%
Isc16.46 A16.7 A1.5%
Impp15.78 A15.92 A0.9%
TcVoc-0.2 %/°C-0.2 %/°C±0.000 %/°C
TcPmax-0.26 %/°C-0.26 %/°C±0.000 %/°C
RECOM RCM-655-8DBRCM

655 W

IBC
94Good match
ParameterOriginalReplacementDeviation
Voc49.62 V49.64 V0.0%
Vmpp40.88 V40.93 V0.1%
Isc16.46 A16.78 A1.9%
Impp15.78 A16 A1.4%
TcVoc-0.2 %/°C-0.2 %/°C±0.000 %/°C
TcPmax-0.26 %/°C-0.26 %/°C±0.000 %/°C
Luxor Solar LX-650M/182R-132+ GG SW PRIME

650 W

TOPCon
94Good match
ParameterOriginalReplacementDeviation
Voc49.62 V49.66 V0.1%
Vmpp40.88 V41.02 V0.3%
Isc16.46 A16.51 A0.3%
Impp15.78 A15.85 A0.4%
TcVoc-0.2 %/°C-0.2 %/°C±0.000 %/°C
TcPmax-0.26 %/°C-0.27 %/°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

49.62 V

Vmpp

40.88 V

Isc

16.46 A

Impp

15.78 A

TcVoc

-0.2 %/°C

TcPmax

-0.26 %/°C

Pmax

645 W

Cells

132

Bifaciality

75%

Length

2382 mm

Width

1134 mm

Thickness

30 mm

Weight

35 kg

The LONGi LR8-66HYD-645M 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
LR8-66HYD-630M630 W49.32 V16.22 A
LR8-66HYD-635M635 W49.42 V16.3 A
LR8-66HYD-640M640 W49.52 V16.38 A
LR8-66HYD-650M650 W49.72 V16.54 A
LR8-66HYD-655M655 W49.82 V16.62 A
LR8-66HYD-660M660 W49.92 V16.7 A
LR8-66HYD-665M665 W50.02 V16.78 A
LR8-66HYD-670M670 W50.12 V16.86 A

Frequently Asked Questions

What specs must match when replacing the LONGi LR8-66HYD-645M?

The most critical specs to match are: cell count (must be exactly 132), Voc close to 49.62 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 LR8-66HYD-645M?

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 LR8-66HYD-645M.