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MicroinverterAPsystems (Altenergy Power Sys…

APsystems (Altenergy Power System) QS1

Name: APsystems (Altenergy Power System) QS1
Brand: APsystems (Altenergy Power System)

Microinverter. 2 models, 1.2 kW AC at 208 V / 240 V.

CEC listed · Mar 1, 2019

Model

Rated AC power1.2 kW
CEC weighted efficiency96.5%

Models & power ratings

CEC Grid Support Inverter List (Oct 7, 2026) · NLR SAM inverter library · 2 models

Model	Nominal AC	Grid voltage	CEC continuous	Rated AC (SAM)	CEC weighted eff.	DC test window	CEC listed	UL 1741 SB
QS1	1.2 kW	208 V	1.22 kW	1.22 kW	96.5%	27–48 V	Mar 11, 2021	—
QS1	1.2 kW	240 V	1.23 kW	1.23 kW	96.5%	27–48 V	Mar 1, 2019	—

DC input (PV side)

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

CEC test DC voltages (min / nom / max)27 / 38 / 48 V
DC input at rated output (CEC test)1.28 kW

Efficiency

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

CEC weighted efficiency96.5%
Night-time standby (tare)0.09 W
Power to start converting6.9 W

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 (3rd ed.)No
UL 1741 SA (SA8–SA13)Yes — CSA Group
Firmware tested (SA)V5
Volt-VAr with reactive power priority (SA13)Yes
Freq-Watt / Volt-Watt (SA14–15)Yes
Disable permit service / limit active power (SA17–18)Yes
CSIP (IEEE 2030.5) conformanceVia gateway during testing (Y*)
Monitor key data & scheduling (Rule 21 Phase 3)Yes (attested Mar 11, 2021)
CEC listedMar 1, 2019
Last CEC updateApr 21, 2020

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

CityColdest air, °CHottest cell, °C

QS1: max DC 48 V · MPPT 27–48 V (CEC test window)

Most-permitted panels in Southern California

Panel	Power	Voc cold / Vmp hot	Check	DC/AC	Installed together
Qcells Q.PEAK DUO BLK ML-G10.C+ 410	410 W	48.1 / 30.6 V	✗ Cold Voc above max input	0.33	—
Qcells Q.PEAK DUO BLK ML-G10+ 410	410 W	48.1 / 30.6 V	✗ Cold Voc above max input	0.33	—
LONGi LR5-54HABB-400M	400 W	39.3 / 25.3 V	⚠ Below MPPT at peak heat	0.33	—
JA Solar JAM54S31-405/MR	405 W	39.4 / 25.5 V	⚠ Below MPPT at peak heat	0.33	—
Hyundai Solutions HiN-T440NF(BK)	440 W	40.9 / 27 V	✓ Within range	0.36	—
Silfab Solar SIL-440QD	440 W	41.1 / 28 V	✓ Within range	0.36	—
Qcells Q.TRON BLK M-G2+ 430	430 W	41.3 / 28 V	✓ Within range	0.35	—
Qcells Q.TRON BLK M-G2.H+ 430	430 W	41.3 / 28 V	✓ Within range	0.35	—
REC Group REC460AA Pure-RX	460 W	68.8 / 47.1 V	✗ Cold Voc above max input	0.38	—
Elin (Sirius PV) ELNSM54M-HC-410	410 W	39.3 / 25.3 V	⚠ Below MPPT at peak heat	0.33	—
Qcells Q.TRON BLK M-G2.C+ 430	430 W	41.3 / 28 V	✓ Within range	0.35	—
Tesla TSP-420	420 W	43.4 / 27.7 V	✓ Within range	0.34	—

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 1.2 kW inverters

CEC Grid Support Inverter List (Oct 7, 2026) · building permits

Inverter	Power	CEC weighted eff.	DC test window	UL 1741 SB	Latest CEC	SoCal permits
APsystems (Altenergy Power System) QS1	1.2 kW–1.2 kW	96.5%	27–48 V	—	2021	0
Hoymiles HM-xxxNT	295 W–1.44 kW	96.5%	29–48 V	11 of 12	2023	3
FOXESS M1-1000-NA	1 kW–1 kW	95.5%	35–50 V	Yes	2026	—
FOXESS M1-xxxx-NA	600 W–1.2 kW	95.5%	35–50 V	Yes	2026	—
APsystems (Altenergy Power System) QSxxxx	1.2 kW–1.92 kW	96.5%	27–48 V	2 of 3	2025	—

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)

ManufacturerAPsystems (Altenergy Power System)
Listed in CEC asAltenergy Power System Inc.
Websiteapsystems.com
Models on CEC lists101

Other series

QSxxxxEZx-LVQT2QTx-480

Documents

manufacturer documents

PDF
4301103202 APsystems Microinverter QS1 for APAC Datasheet Rev1.0 2018-7-26
Datasheet · APsystems · Sep 2018
PDF
4301103202 APsystems Microinverter QS1 for APAC Datasheet Rev1.1 2019-06-26
Datasheet · APsystems · Aug 2019
PDF
4301103202 APsystems Microinverter QS1 for APAC Datasheet Rev1.4 2020-05-13
Datasheet · APsystems · May 2020
PDF
4301103202 APsystems Microinverter QS1 for APAC Datasheet Rev1.3 2020-04-02
Datasheet · APsystems · Apr 2020

Questions & answers

How efficient is the APsystems (Altenergy Power System) QS1?

The California Energy Commission lists a weighted efficiency of 96.5% for APsystems (Altenergy Power System) QS1 models, measured at six power levels and three DC voltages.

What sizes does the APsystems (Altenergy Power System) QS1 come in?

The CEC list includes 2 models from 1.2 kW to 1.2 kW AC: QS1, QS1.

Is the APsystems (Altenergy Power System) QS1 certified to UL 1741 SB?

The CEC list does not show UL 1741 SB certification for these models.

What is the QS1’s DC input voltage range?

CEC tested it at 27–48 V DC.

Sources

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.
APsystems (Altenergy Power System) — document library on the manufacturer’s website (links above).
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, Riverside, Santa Clarita, Chula Vista, Huntington Beach.
California Energy Commission — PV Module List (module electrical data for the compatibility check).
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).