44.6″ · 1,133 mm wide · 1.38″ (35 mm) frame · 48.1 lb (21.8 kg)

Solar panelVSUN (Vietnam Sunergy)

VSUN (Vietnam Sunergy) VSUN400-108M-BB

Name: VSUN (Vietnam Sunergy) VSUN400-108M-BB
Brand: VSUN (Vietnam Sunergy)

108 half-cut cells (12 × 9), PERC. Power classes 390–410 W in the CEC list; datasheet covers 390–405 W.

CEC listed · Dec 13, 2021UL 61730PERCMADE IN VIETNAMInstalled in 1 SoCal permit

Power class

Power (STC)400 WCEC nameplate
Efficiency≥20.5%datasheet minimum
%/°C Pmax−0.404CEC listing test
Performance warranty25 yrdatasheet

Power classes

CEC PV Module List (Oct 7, 2026) · VSUN (Vietnam Sunergy) datasheet · Cali-Graf calculation · 5 models

Model	Pmax	Voc, V	Isc, A	Vmp, V	Imp, A	Efficiency	PTC	CEC listed
VSUN390-108M-BB	390 W	36.84	13.50	30.82	12.66	≥20.0%	358 W	Dec 13, 2021
VSUN395-108M-BB	395 W	37.03	13.59	31.00	12.75	≥20.2%	363 W	Dec 13, 2021
VSUN400-108M-BB	400 W	37.20	13.68	31.17	12.84	≥20.5%	368 W	Dec 13, 2021
VSUN405-108M-BB	405 W	37.36	13.78	31.36	12.92	≥20.8%	373 W	Dec 13, 2021
VSUN410-108M-BB	410 W	37.54	13.86	31.55	13.00	≈21.0%	377 W	Dec 13, 2021

≈ efficiency = Pmax ÷ panel area 1.952 m² (datasheet size) for classes outside the datasheet.

Build & dimensions

VSUN (Vietnam Sunergy) datasheet · Cali-Graf calculation

Dimensions67.8 × 44.6 × 1.38 in1,723 × 1,133 × 35 mm
Module area1.95 m² (21 ft²)length × width
Weight48.1 lb (21.8 kg)
Cells108 half-cut cells (12 × 9)PERC
Front glassWhite toughened safety glass, 3.2 mm
Back coverComposite film
FrameBlack anodized aluminum profile
Junction boxIP68, 3 diodes
Cable / connectorPotrait: 500 mm (cable length can be customized) , 1x4 mm2,
Made inMADE IN VIETNAM

Heat & cold behaviour

CEC PV Module List (Oct 7, 2026) · Cali-Graf calculation · VSUN (Vietnam Sunergy) datasheet

	Datasheet	CEC listing test
Pmax coefficient γ	—	−0.404 %/°C
Voc coefficient β	—	−0.312 %/°C
Isc coefficient α	—	+0.063 %/°C
Vmp coefficient	≈ −0.47 %/°C	—
Operating cell temperature	NMOT 45 °C	NOCT 45.8 °C

Vmp coefficient ≈ γ − α (CEC); used only for the hot-roof voltage estimate.

At normal operating conditions (NOCT, 800 W/m²) — datasheet

Class	Pmax, W	Voc, V	Isc, A	Vmp, V	Imp, A
390 W	287.3	34.50	10.91	28.40	10.10
395 W	294.7	34.80	11.05	28.80	10.25
400 W	298.4	34.90	11.13	28.90	10.32
405 W	302.1	35.10	11.19	29.10	10.39

Away from lab conditions — CEC listing test points

Class	Pmax at NOCT	Vmp × Imp at NOCT	Pmax at 200 W/m²	Low-light efficiency vs STC
390 W	289.3 W	28.58 V × 10.12 A	77.7 W	100%
395 W	293 W	28.75 V × 10.19 A	78.7 W	100%
400 W	296.7 W	28.9 V × 10.27 A	79.7 W	100%
405 W	300.4 W	29.08 V × 10.33 A	80.7 W	100%
410 W	304.1 W	29.25 V × 10.39 A	81.7 W	100%

Pmax = Vmp × Imp from the CEC listing; low-light efficiency = Pmax at 200 W/m² ÷ (20% of STC Pmax).

Electrical & strength ratings

Max system voltage1,000 V
Max series fuse30 A
Protection classclass A
Design load push / pull113 psf5,400 Pa
Module temperature−40 °F to +185 °F−40 °C to +85 °C
Hail25 mm (0.98 in)

Warranty & degradation

VSUN (Vietnam Sunergy) datasheet

Performance warranty25 years, linear

Independent reliability testing

Kiwa PVEL Scorecard · RETC PV Module Index

PVEL Scorecards

VSUN (Vietnam Sunergy) named Top Performer, 2021–2026

2025, 2026

RETC Overall Highest Achiever

VSUN (Vietnam Sunergy), manufacturer level

This exact series is not listed in published PVEL Top Performer tables. Results below are for the manufacturer.

RETC PV Module Index — VSUN (Vietnam Sunergy)

Year	Recognition
2024	Test Category High Achiever
2025	Overall Highest Achiever
2026	Overall Highest Achiever; High achievement in performance; High achievement in reliability; Performance discipline high achiever (Lid, PAN file, Temperature coefficient, Iam, Letid); Quality discipline high achiever (BOM verification); Reliability discipline high achiever (Damp heat, Pid, Sdml, Tc, Uvid)

Inverter compatibility & string sizing

CEC PV Module List (Oct 7, 2026) · Cali-Graf calculation · NLR PVWatts v8 · inverter datasheets · NLR SAM inverter library · CEC Grid Support Inverter List (Oct 7, 2026)

CityColdest air, °CHottest cell, °CString inverter

39.9 V

Voc when cold

per panel

24 V

Vmp when hot

per panel

Max panels / string

max DC 600 V

Min panels / string

MPPT from 60 V

Defaults come from NLR TMY weather (coldest hour, hottest modeled cell). Code calculations (NEC 690.7) use the ASHRAE extreme annual minimum, which is usually colder — enter it above. β is the CEC-measured coefficient; NEC 690.7 calculations use the datasheet value.

String inverters most named in SoCal permits

Inverter	Max DC input	MPPT	Window source	Panels per string
Tesla 1538000-xx-y	600 V	60–480 V	datasheet	3–15
Solis (Ginlong) S6-EH1P10K-H-US	600 V	80–520 V	datasheet	4–15
Solis (Ginlong) Solis-1P7.6K-4G-US	600 V	100–500 V	datasheet	5–15
Qcells Q.VOLT H7.6SX	498 V	234–498 V	CEC test window	10–12

Microinverters (one per panel)

Microinverter	Recommended module power	Max DC input	MPPT	Voc cold / Vmp hot	Check	DC/AC
Enphase IQ8PLUS-72-2-US	235–440 W	60 V	29–45 V	39.9 / 24 V	⚠ Works; below MPPT at peak heat	1.38
Enphase IQ8X-80-M-US	320–540 W	79.5 V	43–60 V	39.9 / 24 V	✗ Not a match: module voltage below MPPT range	1.05
APsystems (Alt Power System) DS3-L	265–570 W	60 V	28–45 V	39.9 / 24 V	⚠ Works; below MPPT at peak heat	0.51
Enphase IQ8M-72-2-US	260–460 W	60 V	30–45 V	39.9 / 24 V	⚠ Works; below MPPT at peak heat	1.23
Enphase IQ8A-72-2-US	295–500 W	60 V	32–45 V	39.9 / 24 V	✗ Not a match: module voltage below MPPT range	1.15

Voltage check against the microinverter datasheets — confirm the pairing on the manufacturer’s module compatibility list. Rows appear only when the panel’s power is inside the microinverter’s recommended module power range.

SolarEdge and other optimizer-based systems size strings by the optimizer rules — use the manufacturer’s designer. Reference inverters: most named in SoCal permits since Oct 2024.

Expected production in Southern California

NLR PVWatts v8 · Cali-Graf calculation

PanelsCity for chartSystem size

City	kWh / kW / yr	kWh / panel / yr	kWh / system / yr	Sun, kWh/m²/day
Los Angeles	1,676	670	12,067	6.08
Palmdale	1,835	734	13,212	6.69
Chula Vista	1,696	678	12,211	6.11
Huntington Beach	1,643	657	11,830	5.89
Riverside	1,696	678	12,211	6.21
Santa Clarita	1,724	690	12,413	6.28

Estimate for comparison, not a quote: shading, roof orientation and local losses change real output. Roof mount, 20° tilt, south, 14% system losses.

Who installs VSUNxxx-108M-BB panels in SoCal

building permits · CSLB License Master

Permits naming this series

Jul 2026

Licensed installers

CSLB license on the permit

Jurisdictions so far

Palmdale (1)

Gonzalez Solar Innovations Inc

Lucerne Valley · CSLB #1141568

1 installJul 2026Palmdale

Only installer and ZIP level is shown — no homeowner names, street addresses or permit numbers. Counts grow as more permit portals are loaded.

Compare with similar 400 W panels

CEC PV Module List (Oct 7, 2026) · Qcells datasheet · Kiwa PVEL Scorecard · building permits

Panel	Pmax	Efficiency	γ Pmax (CEC)	Voc, V	Isc, A	PVEL (product / brand)	SoCal permits (series)
VSUN (Vietnam Sunergy) VSUN400-108M-BB	400 W	≥20.5%	−0.404	37.2	13.68	brand 6×	1
Qcells Q.PEAK DUO BLK ML-G10+ 400	400 W	≥20.4%	−0.362	45.3	11.14	product 2022, 2023	221
JA Solar JAM54S31-400/MR	400 W	≈21.1%	−0.329	37.07	13.79	product 2023, 2024	152
REC Group REC400AA Pure	400 W	≈22.3%	−0.256	48.8	10.25	brand 9× (2016–2025)	66

Same fields from the same sources for every row; ≈ efficiency is calculated from the listed area. Comparable series: other brands, same product group, power range covering this class.

About VSUN (Vietnam Sunergy)

CEC PV Module List (Oct 7, 2026) · Kiwa PVEL Scorecard · RETC PV Module Index · building permits

ManufacturerVSUN (Vietnam Sunergy)
Listed in CEC asVietnam Sunergy Joint Stock Company
Websitevsun-solar.com
PVEL Top Performer (manufacturer)6 Scorecards (2021–2026)
RETC PV Module Index2024, 2025, 2026
Current panel series in CEC list82

Other series by SoCal permits

VSUNxxxN-108BMH-BB · 4VSUNxxxN-108MH-BB · 3VSUNxxxN-144MH · 1VSUNxxx-108BMH · 1VSUNxxxN-108BMHVSUNxxxN-108BMH-BT

Questions & answers

How efficient is the VSUN (Vietnam Sunergy) VSUN400-108M-BB?

The VSUN (Vietnam Sunergy) datasheet guarantees at least 20.5% module efficiency for the 400 W class (up to 20.8% for 405 W). 400 W over 1.95 m² equals about 205 W per square meter.

How much energy does one panel produce in Los Angeles or Palmdale?

PVWatts v8 with typical-year weather gives about 670 kWh per year per 400 W panel in Los Angeles and about 734 kWh in Palmdale (20° roof, facing south, 14% system losses).

How much power does it lose on a hot roof?

With γ = −0.404 %/°C, at a 77 °C cell temperature (hottest modeled hour in Palmdale) output is about 20.9% below the STC rating.

How many panels fit on one string?

With the Tesla 1538000-xx-y (max DC 600 V, MPPT from 60 V, datasheet) in Los Angeles the calculator gives 3–15 panels per string (Voc at 2 °C = 39.9 V, Vmp at 74 °C cell = 24 V). Final design must follow the inverter manual and NEC 690.7.

What does the warranty cover?

25 years linear on performance (manufacturer datasheet).

How big and heavy is it?

67.8 × 44.6 × 1.38 in (1,723 × 1,133 × 35 mm), 48.1 lb (21.8 kg).

Has this panel been reliability-tested?

This exact series is not in published PVEL Top Performer tables; VSUN (Vietnam Sunergy) was named a Top Performer in 6 Scorecards (2021–2026). RETC named VSUN (Vietnam Sunergy) Overall Highest Achiever in 2025, 2026.

Who installs it in Southern California?

Building permits name this series 1 times (Jul 2026). The most active licensed installers are Gonzalez Solar Innovations Inc.

Sources

California Energy Commission — Solar Equipment Lists, PV Module List, Inverter List (snapshot Oct 7, 2026).
VSUN (Vietnam Sunergy) — manufacturer datasheet “MADE IN VIETNAM, manufacture by VIETNAM SUNERGY JOINT STOCK COMPANY”.
Qcells — manufacturer datasheet “Q.PEAK DUO BLK ML-G10+ ENDURING HIGH PERFORMANCE”.
Kiwa PVEL — PV Module Reliability Scorecard, Top Performer lists 2021–2026.
RETC — PV Module Index reports 2024–2026.
NLR (formerly NREL) — System Advisor Model CEC inverter library (version 2026.7.3).
NLR (formerly NREL) — PVWatts v8, NSRDB PSM v3 typical-year weather for Los Angeles, Palmdale, Chula Vista, Huntington Beach, Riverside, Santa Clarita.
Inverter datasheets — APsystems (Alt Power System), Enphase, Solis (Ginlong), Tesla (manufacturer documents).
Building permits — City of Palmdale (Jul 2026). Equipment matched from permit descriptions by model number.
Contractors State License Board — License Master (contractor names and license status), as of Oct 5, 2026.
Cali-Graf calculations — formulas and inputs are shown next to each calculated value (efficiency from area, temperature-corrected voltages, string sizing, energy estimates).