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MicroinverterHoymiles

Hoymiles HMS-1200-4T

Microinverter. 3 models, 1 kW–1.5 kW AC at 240 V.

CEC listed · Mar 1, 2021

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 · 3 models

Model	Nominal AC	Grid voltage	CEC continuous	Rated AC (SAM)	CEC weighted eff.	DC test window	CEC listed	UL 1741 SB
HMS-1000-4T	1 kW	240 V	1.03 kW	1.03 kW	96.5%	27–48 V	Mar 1, 2021	—
HMS-1200-4T	1.2 kW	240 V	1.21 kW	1.21 kW	96.5%	32–48 V	Mar 1, 2021	—
HMS-1500-4T	1.5 kW	240 V	1.55 kW	1.55 kW	96.5%	36–48 V	Mar 1, 2021	—

DC input (PV side)

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

CEC test DC voltages (min / nom / max)32 / 40 / 48 V
DC input at rated output (CEC test)1.26 kW

Efficiency

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

CEC weighted efficiency96.5%
Night-time standby (tare)0.01 W
Power to start converting3.6 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)V01.01.00
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 1, 2021)
CEC listedMar 1, 2021

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

HMS-1200-4T: max DC 48 V · MPPT 32–48 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	0.34	—
Qcells Q.PEAK DUO BLK ML-G10+ 410	410 W	48.1 / 30.6 V	✗ Cold Voc above max input	0.34	—
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	⚠ Below MPPT at peak heat	0.36	—
Silfab Solar SIL-440QD	440 W	41.1 / 28 V	⚠ Below MPPT at peak heat	0.36	—
Qcells Q.TRON BLK M-G2+ 430	430 W	41.3 / 28 V	⚠ Below MPPT at peak heat	0.35	—
Qcells Q.TRON BLK M-G2.H+ 430	430 W	41.3 / 28 V	⚠ Below MPPT at peak heat	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	0.34	—
Qcells Q.TRON BLK M-G2.C+ 430	430 W	41.3 / 28 V	⚠ Below MPPT at peak heat	0.35	—
Tesla TSP-420	420 W	43.4 / 27.7 V	⚠ Below MPPT at peak heat	0.35	—

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
Hoymiles HMS-xxxx-4T	1 kW–1.5 kW	96.5%	32–48 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 Hoymiles

CEC Grid Support Inverter List (Oct 7, 2026)

ManufacturerHoymiles
Listed in CEC asHoymiles Power Electronics Inc.
Websitehoymiles.com
Models on CEC lists402

Other series

HM-xxxNT · 3 permitsHMS-xxx-1WM-LVMIS-xxx-1A-NAMIS-xxx-1NAMIS-xxx-2NAHMT-xxxx-4T-208-NAHM-xxxNHMS-xxx-1A-NAHMS-xxx-1T-NAHMS-xxx-2T-NAHMS-xxxx-4T-NAHMS-xxx-1D-NA

Questions & answers

How efficient is the Hoymiles HMS-xxxx-4T?

The California Energy Commission lists a weighted efficiency of 96.5% for Hoymiles HMS-xxxx-4T models, measured at six power levels and three DC voltages.

What sizes does the Hoymiles HMS-xxxx-4T come in?

The CEC list includes 3 models from 1 kW to 1.5 kW AC: HMS-1000-4T, HMS-1200-4T, HMS-1500-4T.

Is the Hoymiles HMS-xxxx-4T certified to UL 1741 SB?

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

What is the HMS-1200-4T’s DC input voltage range?

CEC tested it at 32–48 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.
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).