Find replacement for Heckert Solar ZEUS 2.1 132-640

640 W TOPCon solar panel with 132 cells. Voc 49.75 V · Isc 16.33 A · TcVoc -0.24%/°C.

Original Panel

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Same technology onlyShow only panels with matching cell technology

Compatible Replacements

188 panels found · 3512 panels excluded

Tongwei TWMNH-66HD640

640 W

TOPCon

100Exact match

Parameter	Original	Replacement	Deviation
Voc	49.75 V	49.75 V	0.0%
Vmpp	41.38 V	41.38 V	0.0%
Isc	16.33 A	16.33 A	0.0%
Impp	15.47 A	15.47 A	0.0%
TcVoc	-0.24 %/°C	-0.24 %/°C	±0.000 %/°C
TcPmax	-0.28 %/°C	-0.28 %/°C	±0.000 %/°C

Tongwei TWMNH-66HD645

645 W

TOPCon

95Exact match

Parameter	Original	Replacement	Deviation
Voc	49.75 V	49.85 V	0.2%
Vmpp	41.38 V	41.51 V	0.3%
Isc	16.33 A	16.39 A	0.4%
Impp	15.47 A	15.54 A	0.5%
TcVoc	-0.24 %/°C	-0.24 %/°C	±0.000 %/°C
TcPmax	-0.28 %/°C	-0.28 %/°C	±0.000 %/°C

Tongwei TWMNH-66HD635

635 W

TOPCon

94Good match

Parameter	Original	Replacement	Deviation
Voc	49.75 V	49.6 V	0.3%
Vmpp	41.38 V	41.24 V	0.3%
Isc	16.33 A	16.26 A	0.4%
Impp	15.47 A	15.4 A	0.5%
TcVoc	-0.24 %/°C	-0.24 %/°C	±0.000 %/°C
TcPmax	-0.28 %/°C	-0.28 %/°C	±0.000 %/°C

Heckert Solar ZEUS 2.1 132-635

635 W

TOPCon

94Good match

Parameter	Original	Replacement	Deviation
Voc	49.75 V	49.6 V	0.3%
Vmpp	41.38 V	41.24 V	0.3%
Isc	16.33 A	16.26 A	0.4%
Impp	15.47 A	15.4 A	0.5%
TcVoc	-0.24 %/°C	-0.24 %/°C	±0.000 %/°C
TcPmax	-0.28 %/°C	-0.28 %/°C	±0.000 %/°C

Trina Solar TSM-NEG19RC.20-650

650 W

TOPCon

93Good match

Parameter	Original	Replacement	Deviation
Voc	49.75 V	49.77 V	0.0%
Vmpp	41.38 V	41.43 V	0.1%
Isc	16.33 A	16.59 A	1.6%
Impp	15.47 A	15.69 A	1.4%
TcVoc	-0.24 %/°C	-0.24 %/°C	±0.000 %/°C
TcPmax	-0.28 %/°C	-0.29 %/°C	±0.010 %/°C

Yingli Solar YL640CF66 i/2

640 W

TOPCon

91Good match

Parameter	Original	Replacement	Deviation
Voc	49.75 V	49.8 V	0.1%
Vmpp	41.38 V	41.8 V	1.0%
Isc	16.33 A	16.32 A	0.1%
Impp	15.47 A	15.31 A	1.0%
TcVoc	-0.24 %/°C	-0.24 %/°C	±0.000 %/°C
TcPmax	-0.28 %/°C	-0.29 %/°C	±0.010 %/°C

Yingli Solar YL635CF66 i/2

635 W

TOPCon

90Good match

Parameter	Original	Replacement	Deviation
Voc	49.75 V	49.62 V	0.3%
Vmpp	41.38 V	41.64 V	0.6%
Isc	16.33 A	16.25 A	0.5%
Impp	15.47 A	15.25 A	1.4%
TcVoc	-0.24 %/°C	-0.24 %/°C	±0.000 %/°C
TcPmax	-0.28 %/°C	-0.29 %/°C	±0.010 %/°C

Tongwei TWMNH-66HD650

650 W

TOPCon

89Good match

Parameter	Original	Replacement	Deviation
Voc	49.75 V	50 V	0.5%
Vmpp	41.38 V	41.65 V	0.7%
Isc	16.33 A	16.45 A	0.7%
Impp	15.47 A	15.61 A	0.9%
TcVoc	-0.24 %/°C	-0.24 %/°C	±0.000 %/°C
TcPmax	-0.28 %/°C	-0.28 %/°C	±0.000 %/°C

DMEGC GH635G12RT-B66HST

635 W

TOPCon

89Good match

Parameter	Original	Replacement	Deviation
Voc	49.75 V	49.69 V	0.1%
Vmpp	41.38 V	41.45 V	0.2%
Isc	16.33 A	16.29 A	0.2%
Impp	15.47 A	15.35 A	0.8%
TcVoc	-0.24 %/°C	-0.25 %/°C	±0.010 %/°C
TcPmax	-0.28 %/°C	-0.29 %/°C	±0.010 %/°C

DMEGC DM635G12RT-B66HSW

635 W

TOPCon

89Good match

Parameter	Original	Replacement	Deviation
Voc	49.75 V	49.69 V	0.1%
Vmpp	41.38 V	41.45 V	0.2%
Isc	16.33 A	16.29 A	0.2%
Impp	15.47 A	15.35 A	0.8%
TcVoc	-0.24 %/°C	-0.25 %/°C	±0.010 %/°C
TcPmax	-0.28 %/°C	-0.29 %/°C	±0.010 %/°C

Suntech STP635S-H66-Nsh+

635 W

TOPCon

89Good match

Parameter	Original	Replacement	Deviation
Voc	49.75 V	49.7 V	0.1%
Vmpp	41.38 V	41.31 V	0.2%
Isc	16.33 A	16.25 A	0.5%
Impp	15.47 A	15.37 A	0.6%
TcVoc	-0.24 %/°C	-0.25 %/°C	±0.010 %/°C
TcPmax	-0.28 %/°C	-0.29 %/°C	±0.010 %/°C

JinkoSolar JKM640N-66HL4M-BDV

640 W

TOPCon

88Good match

Parameter	Original	Replacement	Deviation
Voc	49.75 V	49.88 V	0.3%
Vmpp	41.38 V	41.3 V	0.2%
Isc	16.33 A	16.32 A	0.1%
Impp	15.47 A	15.5 A	0.2%
TcVoc	-0.24 %/°C	-0.25 %/°C	±0.010 %/°C
TcPmax	-0.28 %/°C	-0.29 %/°C	±0.010 %/°C

String Compatibility Calculator

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Panel Matcher

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Original Panel Specs

Voc

49.75 V

Vmpp

41.38 V

Isc

16.33 A

Impp

15.47 A

TcVoc

-0.24 %/°C

TcPmax

-0.28 %/°C

Pmax

640 W

Cells

132

Bifaciality

80%

Length

2382 mm

Width

1134 mm

Thickness

30 mm

Weight

32.5 kg

The Heckert Solar ZEUS 2.1 132-640 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

Power	Voc	Isc
620 W	49.1 V	16.06 A
625 W	49.3 V	16.12 A
630 W	49.5 V	16.18 A
635 W	49.6 V	16.26 A

Frequently Asked Questions

What specs must match when replacing the Heckert Solar ZEUS 2.1 132-640?

The most critical specs to match are: cell count (must be exactly 132), Voc close to 49.75 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 Heckert Solar ZEUS 2.1 132-640?

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 Heckert Solar ZEUS 2.1 132-640.