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MicroinverterAPsystems (Altenergy Power Sys…

APsystems (Altenergy Power System) QT2

Microinverter. 2 models, 1.73 kW–1.8 kW AC at 208 V / 480 V.

UL 1741 SBCEC listed · Oct 3, 2022
Model
  • Rated AC power1.8 kW
  • CEC weighted efficiency95.5%

Models & power ratings

CEC Grid Support Inverter List (Oct 7, 2026) · NLR SAM inverter library · 2 models
ModelNominal ACGrid voltageCEC continuousRated AC (SAM)CEC weighted eff.DC test windowCEC listedUL 1741 SB
QT21.73 kW208 V1.73 kW1.73 kW96.0%34–42 VOct 3, 2022SB
QT21.8 kW480 V1.82 kW1.82 kW95.5%34–42 VOct 3, 2022SB

DC input (PV side)

CEC Grid Support Inverter List (Oct 7, 2026) · NLR SAM inverter library

Efficiency

CEC Grid Support Inverter List (Oct 7, 2026) · NLR SAM inverter library
CEC weighted efficiency is measured by an accredited lab at six power levels and three DC voltages — the number to compare between inverters.

Grid & smart-inverter certification

CEC Grid Support Inverter List (Oct 7, 2026)
UL 1741 SB is required for new interconnections in California (Rule 21) since 2026.

Panel compatibility & string sizing

NLR SAM inverter library · NLR PVWatts v8 · CEC PV Module List · Cali-Graf calculation
QT2: max DC 42 V · MPPT 34–42 V (CEC test window)

Most-permitted panels in Southern California

PanelPowerVoc cold / Vmp hotCheckDC/ACInstalled together
Qcells Q.PEAK DUO BLK ML-G10.C+ 410410 W48.1 / 30.6 V✗ Cold Voc above max input0.23—
Qcells Q.PEAK DUO BLK ML-G10+ 410410 W48.1 / 30.6 V✗ Cold Voc above max input0.23—
LONGi LR5-54HABB-400M400 W39.3 / 25.3 V⚠ Below MPPT at peak heat0.22—
JA Solar JAM54S31-405/MR405 W39.4 / 25.5 V⚠ Below MPPT at peak heat0.22—
Hyundai Solutions HiN-T440NF(BK)440 W40.9 / 27 V⚠ Below MPPT at peak heat0.24—
Silfab Solar SIL-440QD440 W41.1 / 28 V⚠ Below MPPT at peak heat0.24—
Qcells Q.TRON BLK M-G2+ 430430 W41.3 / 28 V⚠ Below MPPT at peak heat0.24—
Qcells Q.TRON BLK M-G2.H+ 430430 W41.3 / 28 V⚠ Below MPPT at peak heat0.24—
REC Group REC460AA Pure-RX460 W68.8 / 47.1 V✗ Cold Voc above max input0.25—
Elin (Sirius PV) ELNSM54M-HC-410410 W39.3 / 25.3 V⚠ Below MPPT at peak heat0.23—
Qcells Q.TRON BLK M-G2.C+ 430430 W41.3 / 28 V⚠ Below MPPT at peak heat0.24—
Tesla TSP-420420 W43.4 / 27.7 V✗ Cold Voc above max input0.23—
Voltage check only, from CEC panel data and NLR weather for the city. Final design must follow the inverter manual and NEC 690.7.

Compare with similar 1.8 kW inverters

CEC Grid Support Inverter List (Oct 7, 2026) · building permits
InverterPowerCEC weighted eff.DC test windowUL 1741 SBLatest CECSoCal permits
APsystems (Altenergy Power System) QT21.73 kW–1.8 kW95.5%34–42 VYes20220
APsystems (Altenergy Power System) QTx-4801.8 kW–1.8 kW95.5%34–42 VYes2022—
Same type and grid voltage, power range covering this model; same fields from the same sources.

About APsystems (Altenergy Power System)

CEC Grid Support Inverter List (Oct 7, 2026)

Other series

QSxxxxEZx-LVQTx-480QS1

Documents

manufacturer documents

Questions & answers

How efficient is the APsystems (Altenergy Power System) QT2?

The California Energy Commission lists a weighted efficiency of 95.5–96.0% for APsystems (Altenergy Power System) QT2 models, measured at six power levels and three DC voltages.

What sizes does the APsystems (Altenergy Power System) QT2 come in?

The CEC list includes 2 models from 1.73 kW to 1.8 kW AC: QT2, QT2.

Is the APsystems (Altenergy Power System) QT2 certified to UL 1741 SB?

Yes — the CEC Grid Support Inverter List shows UL 1741 SB for all models.

What is the QT2’s DC input voltage range?

CEC tested it at 34–42 V DC.

Sources

  1. California Energy Commission — Grid Support Inverter List (solar and battery inverters), data as of Oct 7, 2026. Manufacturer-reported, confirmed by CEC against certificates and test reports.
  2. APsystems (Altenergy Power System) — document library on the manufacturer’s website (links above).
  3. NLR (formerly NREL) — System Advisor Model CEC inverter library (version 2026.7.3).
  4. NLR (formerly NREL) — PVWatts v8, NSRDB PSM v3 typical-year weather for Los Angeles, Palmdale, Riverside, Santa Clarita, Chula Vista, Huntington Beach.
  5. California Energy Commission — PV Module List (module electrical data for the compatibility check).
  6. Building permits — Southern California permit portals. Equipment matched from permit descriptions.
  7. Cali-Graf calculations — formulas and inputs are shown next to each calculated value (efficiency from area, temperature-corrected voltages, string sizing, energy estimates).