SAJ Home Battery and Inverter

An SAJ inverter is a hybrid inverter: a single unit that combines the MPPT trackers for the solar panels, the battery charger, and the grid-tie inverter. SAJ Electric, based in Guangzhou, has been manufacturing inverters since 2005 and has been TÜV-certified for the European market since 2011. The brand has opted for its own ecosystem: the inverter, battery modules, backup module, wallbox, and app are all manufactured in-house and have been tested together. This saves you, as an installer, the hassle of compatibility lists and firmware conflicts.

The inverters are IP65-rated and are therefore installed indoors or outdoors under a canopy. In Europe, SAJ offers a standard 10-year warranty on the inverter; an extension is available for a fee.

An SAJ home battery consists of a hybrid inverter and one to eight 5-kWh battery modules that you stack underneath the inverter. During the day, the inverter charges the modules with excess PV power; in the evening, it discharges power to the appliances in the home. The digital meter measures consumption every 15 minutes; the inverter adjusts its output accordingly, with the goal of keeping the 15-minute peak low to minimize the capacity charge and maximize self-consumption.

The control system is built into Elekeeper, SAJ’s energy management software. The AI Savings feature learns the household’s consumption profile and the weather forecast, and uses that information to determine when the battery should charge and discharge. With a dynamic contract, the system also draws power from the grid when the hourly rate is low. The owner monitors everything in the SAJ Home App; as an installer, you can view the same data in the installer portal, including error messages for each device.

1. SAJ HS3: compact, single-phase, and three-phase

The HS3 is 17 cm deep and combines six functions in a single wall-mounted unit: PV inverter, battery inverter, battery, backup, energy management, and—optionally—an integrated 7- or 11-kW charging station. The HS3 is available as a single-phase and three-phase versions; the inverter achieves an efficiency of up to 98%. A built-in heating system keeps the cells operational down to -30 °C, and an automatic fire suppression system activates in case of overheating. Capacity: 5 to 40 kWh, in 5-kWh increments.

2. SAJ AS3: for residential properties and small and medium-sized enterprises

The AS3 shares the modular design with the HS3, but is geared toward installations with higher energy consumption: independent professionals, small workshops, and homes with a heat pump and two electric cars. The AS3 is also available in single-phase and three-phase versions. The three-phase version balances the three phases individually, which further reduces the quarter-hourly peak in the case of a three-phase connection with unevenly loaded phases.

3. SAJ CHS2: 57–100 kWh charging station for businesses

The CHS2 is a fully pre-programmed battery cabinet for outdoor installation: a 29.9 or 50 kW SAJ inverter, 4 modules totaling 57.3 kWh or 7 modules totaling 100.3 kWh (usable capacity 54.43 to 95.28 kWh at 95% DoD), EMS, a fire suppression system, and active air conditioning with cell monitoring. The cabinet measures 988 × 1,065 × 1,980 mm without the inverter. This is the entry-level solution for an SME seeking peak shaving without a container; for higher capacities, check out our cabinet battery systems.

4. Caro Series Wallbox

The Caro Series is SAJ’s 7- or 11-kW AC charging station, which can be controlled using surplus PV power via the same app as the battery. More charging solutions can be found on our page featuring charging stations.

The correct configuration is determined by three pieces of information provided by the customer: annual consumption, the connection type, and the PV capacity.

• Single-phase or three-phase: follow the connection. A three-phase connection requires a three-phase inverter; otherwise, the peak will remain on a single phase.
• Inverter capacity: equal to or slightly less than the PV capacity in kWp; in the case of a heat pump and charging station, it tends to be higher to accommodate the backup function.
• Battery capacity: daily consumption between sunset and sunrise, typically 10 to 15 kWh for a household with a heat pump. With SAJ, you can start with a modular system and expand it later without needing a new inverter.

If you're unsure, please send us the consumption and PV data; we'll calculate the configuration and provide the bill of materials.

The all-in-one unit is mounted on the wall using a mounting bracket; slide the modules underneath it and connect them to each other using the DC connectors. The connection to the meter is made via a CT clamp or a metering module on the digital meter. You connect the inverter to Wi-Fi or Ethernet via the app: scan the QR code on the nameplate, select the network, and the inverter will register itself in the portal. Then, request the AREI inspection from a certified inspection agency and register the battery and inverter with Fluvius. The SAJ inverters are listed on the Synergrid C10/26 list; we provide the certificates with every order.

Existing customers can order the HS3, AS3, CHS2, and Caro directly from the online store. If you’d like to have a configuration quoted or need assistance with the inspection and Fluvius registration, please contact us; we’ll include the bill of materials, certificates, and settings with your order.