Details describe the tested sample, not every module of the series.
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)
45.5 V
Voc when cold
per panel
29.4 V
Vmp when hot
per panel
13
Max panels / string
max DC 600 V
3
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
3–13
Solis (Ginlong) S6-EH1P10K-H-US
600 V
80–520 V
datasheet
3–13
Solis (Ginlong) Solis-1P7.6K-4G-US
600 V
100–500 V
datasheet
4–13
Qcells Q.VOLT H7.6SX
498 V
234–498 V
CEC test window
8–10
Microinverters (one per panel)
Microinverter
Recommended module power
Max DC input
MPPT
Voc cold / Vmp hot
Check
DC/AC
Enphase IQ8X-80-M-US
320–540 W
79.5 V
43–60 V
45.5 / 29.4 V
✗ Not a match: module voltage below MPPT range
1.25
APsystems (Alt Power System) DS3-L
265–570 W
60 V
28–45 V
45.5 / 29.4 V
✓ Within range
0.61
Enphase IQ8A-72-2-US
295–500 W
60 V
32–45 V
45.5 / 29.4 V
⚠ Works; below MPPT at peak heat
1.36
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
City
kWh / kW / yr
kWh / panel / yr
kWh / system / yr
Sun, kWh/m²/day
Los Angeles
1,676
796
11,942
6.08
Palmdale
1,835
872
13,074
6.69
Chula Vista
1,696
806
12,084
6.11
Huntington Beach
1,643
780
11,706
5.89
Riverside
1,696
806
12,084
6.21
Santa Clarita
1,724
819
12,284
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.
Compare with similar 475 W panels
CEC PV Module List (Oct 7, 2026) · Kiwa PVEL Scorecard · datasheets · building permits
Panel
Pmax
Efficiency
γ Pmax (CEC)
Voc, V
Isc, A
PVEL (product / brand)
SoCal permits (series)
VSUN (Vietnam Sunergy) VSUN475N-120MH
475 W
≈22%
−0.345
42.78
13.78
brand 6×
—
REC Group REC475AA Pure-RX
475 W
≈23.5%
−0.248
65.7
9
brand 9× (2016–2025)
33
SEG Solar SEG-455-BTD-BG
455 W
≈23.3%
−0.262
39.76
14.11
product 2023, 2024, 2025, 2026
8
Qcells Q.PEAK DUO XL-G10.d 475
475 W
≥20.5%
−0.340
53.58
11.24
product 2023
6
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
How efficient is the VSUN (Vietnam Sunergy) VSUN475N-120MH?
Calculated from the panel area (2.16 m²): about 22% for the 475 W class. 475 W over 2.16 m² equals about 220 W per square meter.
How much energy does one panel produce in Los Angeles or Palmdale?
PVWatts v8 with typical-year weather gives about 796 kWh per year per 475 W panel in Los Angeles and about 872 kWh in Palmdale (20° roof, facing south, 14% system losses).
How much power does it lose on a hot roof?
With γ = −0.345 %/°C, at a 77 °C cell temperature (hottest modeled hour in Palmdale) output is about 17.8% 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 3–13 panels per string (Voc at 2 °C = 45.5 V, Vmp at 74 °C cell = 29.4 V). Final design must follow the inverter manual and NEC 690.7.
Does it work with APsystems (Alt Power System) DS3-L microinverters?
Voltage check against the APsystems (Alt Power System) datasheet: Voc when cold 45.5 V vs max input 60 V; Vmp when hot 29.4 V vs MPPT low 28 V; recommended module power 265–570 W. Confirm on the microinverter maker’s compatibility list.
Has this panel been reliability-tested?
VSUNxxxN-120MH-BB was a PVEL Top Performer in 2024 (LID+LETID) — a closely related product name.
Sources
California Energy Commission — Solar Equipment Lists, PV Module List, Inverter List (snapshot Oct 7, 2026).
SEG Solar — manufacturer datasheet “XXXTFHTPMBSDPN YUKON/Series )BMG$FMM/5ZQF501$PO”.
Qcells — manufacturer datasheet “Q.PEAK DUO XL-G10.d ENDURING HIGH PERFORMANCE”.
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 — Southern California permit portals. Equipment matched from permit descriptions.
Cali-Graf calculations — formulas and inputs are shown next to each calculated value (efficiency from area, temperature-corrected voltages, string sizing, energy estimates).
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