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Battery inverterWSTECH

WSTECH APS800-ES-1-440-5

Battery inverter, ac-coupled battery inverter. 1 model, 800 kW AC at 440 V.

CEC listed · Nov 12, 2020

Rated AC power800 kW
CEC weighted efficiency97.5%

AC output (grid side)

CEC Grid Support Inverter List (Oct 7, 2026)

Rated AC power800 kW
CEC-measured continuous output814.2 kW
Grid voltage440 V
Phase3-phase 440 V

Efficiency

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

CEC weighted efficiency97.5%
Night-time standby (tare)91.4 W
Power to start converting1,992.1 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 V2040
Volt-VAr with reactive power priority (SA13)Yes
Freq-Watt / Volt-Watt (SA14–15)Yes
Disable permit service / limit active power (SA17–18)No
CSIP (IEEE 2030.5) conformanceNo
Monitor key data & scheduling (Rule 21 Phase 3)No
CEC listedNov 12, 2020
CEC noteEfficiency data inclusive of transformer effect based on 1000 kVA Low-Voltage Dry-Type Distribution Transformers Table in DOE216.

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

About WSTECH

CEC Grid Support Inverter List (Oct 7, 2026)

ManufacturerWSTECH
Listed in CEC asWSTECH GmbH
Models on CEC lists8

Other series

APSxxx-ES-1-480-5

Questions & answers

How efficient is the WSTECH APSxxx-ES-1-440-5?

The California Energy Commission lists a weighted efficiency of 97.5% for WSTECH APSxxx-ES-1-440-5 models, measured at six power levels and three DC voltages.

Is the WSTECH APSxxx-ES-1-440-5 certified to UL 1741 SB?

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

Can the WSTECH APSxxx-ES-1-440-5 be used with a battery?

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

What is the APS800-ES-1-440-5’s DC input voltage range?

CEC tested it at 648–1,500 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).