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Battery inverterWSTECH

WSTECH APS870-ES-1-480-5

Battery inverter, ac-coupled battery inverter. 1 model, 870 kW AC at 480 V.

CEC listed · Jul 1, 2021

Rated AC power870 kW
CEC weighted efficiency98.0%

AC output (grid side)

CEC Grid Support Inverter List (Oct 7, 2026)

Rated AC power870 kW
CEC-measured continuous output872 kW
Grid voltage480 V
Phase3-phase 480 V

Efficiency

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

CEC weighted efficiency98.0%
Night-time standby (tare)91.4 W
Power to start converting2,670.9 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 — MET
Firmware tested (SA)APU V3130 APMC V2050
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) conformanceNo
Monitor key data & scheduling (Rule 21 Phase 3)No
CEC listedJul 1, 2021

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

Compare with similar 870 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
WSTECH APSxxx-ES-1-480-5	870 kW–870 kW	98.0%	770–1,470 V	—	2021	0
EPC Power 50-100100	450 kW–1,500 kW	98.0%	400–1,250 V	Yes	2021	—

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

About WSTECH

CEC Grid Support Inverter List (Oct 7, 2026)

ManufacturerWSTECH
Listed in CEC asWSTECH GmbH
Models on CEC lists8

Other series

APSxxx-ES-1-440-5

Questions & answers

How efficient is the WSTECH APSxxx-ES-1-480-5?

The California Energy Commission lists a weighted efficiency of 98.0% for WSTECH APSxxx-ES-1-480-5 models, measured at six power levels and three DC voltages.

Is the WSTECH APSxxx-ES-1-480-5 certified to UL 1741 SB?

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

Can the WSTECH APSxxx-ES-1-480-5 be used with a battery?

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

What is the APS870-ES-1-480-5’s DC input voltage range?

CEC tested it at 770–1,470 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.