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Battery inverterKowint Energy

Kowint Energy K-PH125-B-US03

Battery inverter, ac-coupled battery inverter. 1 model, 125 kW AC at 480 V.

UL 1741 SBCEC listed · Feb 3, 2025

Rated AC power125 kW
CEC weighted efficiency98.5%

AC output (grid side)

CEC Grid Support Inverter List (Oct 7, 2026)

Rated AC power125 kW
CEC-measured continuous output125 kW
Grid voltage480 V
Phase3-phase 480 V

Efficiency

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

CEC weighted efficiency98.5%
Night-time standby (tare)60 W
Power to start converting76.9 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.)Yes — Intertek, certificate Sep 27, 2024
UL 1741 SA (SA8–SA13)No
Volt-VAr with reactive power priority (SA13)No
Freq-Watt / Volt-Watt (SA14–15)No
Disable permit service / limit active power (SA17–18)No
CSIP (IEEE 2030.5) conformanceNo
Monitor key data & scheduling (Rule 21 Phase 3)No
CEC listedFeb 3, 2025

UL 1741 SB is required for new interconnections in California (Rule 21) since 2026.

Compare with similar 125 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
Kowint Energy K-PHxxx-B-US03	125 kW–125 kW	98.5%	720–1,300 V	Yes	2025	0
Kehua BCSxxK-B-HM-US X2	75 kW–175 kW	98.5%	720–1,450 V	Yes	2024	—
Growatt WIT xxK-A-US	50 kW–100 kW	99.0%	750–900 V	Yes	2024	—
Growatt WIT xxK-AU-US	50 kW–100 kW	99.0%	750–900 V	Yes	2024	—
CPS (Chint Power Systems) CPS ECBxx.xKTL-M/US-480	62.5 kW–125 kW	97.5%	750–1,100 V	Yes	2020	—

Same type and grid voltage, power range covering this model; same fields from the same sources.

Questions & answers

How efficient is the Kowint Energy K-PHxxx-B-US03?

The California Energy Commission lists a weighted efficiency of 98.5% for Kowint Energy K-PHxxx-B-US03 models, measured at six power levels and three DC voltages.

Is the Kowint Energy K-PHxxx-B-US03 certified to UL 1741 SB?

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

Can the Kowint Energy K-PHxxx-B-US03 be used with a battery?

The CEC lists it as a ac-coupled battery inverter.

What is the K-PH125-B-US03’s DC input voltage range?

CEC tested it at 720–1,300 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).
Building permits — Southern California permit portals. Equipment matched from permit descriptions.