You can also use a photovoltaic system without storage and only consume the electricity when it's generated. However, a home battery offers several advantages:

• Independence: both regarding energy supply and independent of rising energy prices. Safety during power outages (emergency power).
• Economic return: the battery is an investment that pays for itself once it is written off.
• Sustainability: You can utilise a greater share of your self-generated solar energy – generated in an environmentally friendly way and consumed directly on site.
  

Because SAX systems lack a separate inverter for the battery – unlike conventional systems – the entire system is very compact. In the 5.8 kWh version, the battery is only the size 53 × 53 × 25 cm and can be easily integrated.

The battery is controlled by a smart meter, ideally installed by an electrician behind the electricity meter. This smart meter measures both the generated power that is fed back into the grid and the power drawn from the grid. The smart meter optimizes operation so that excess PV power is stored and used when needed. No power is fed back into the public grid, nor is any power drawn from the grid, as this is not economically viable.

With SAX storage, you get an extremely high level of safety: the system can be shut down within 0.2 milliseconds, after which the entire storage falls below the safe voltage of 40V – so you can touch it anywhere! This prevents accidents due to high voltage or overheating. The service life also benefits: conventional battery systems with series connections are only as strong as their weakest cell, and production variations and, above all, aging always result in losses. With the SAX circuit, the cell blocks are controlled individually, so that each cell can be optimally utilized. Even if one cell fails completely, the rest of the battery remains usable. The system is also extremely robust, because thanks to the special circuit, the electronic components are only exposed to a low voltage – significantly reducing the risk of failure.

The revolutionary approach of SAX technology has been confirmed by independent bodies such as the Fraunhofer Institute – the accompanying documents are available upon request. American investor Walden International also thoroughly tested SAX and its technology before investing a seven-figure sum in 2021. Furthermore, SAX received recognition through awards at renowned competitions: the German Innovation Award in May 2021 and the ees Award in July 2021, presented by Intersolar, the world's leading trade fair series for the solar energy industry. SAX will again be presenting its storage systems at this year's Intersolar trade fair in Munich in October.

A clear dashboard allows you to monitor the battery in your web browser and a smartphone app. Data such as charge status can be viewed, measurement data is displayed graphically, and the battery can be switched on and off. After delivery, you can create an account using the battery's serial number (website: app.sax-power.net). The SAX batteries are connected to the SAX Power web server via a LAN interface. The values are also stored in a database and are therefore available for maintenance purposes.

Yes, there's a separate connection on the housing next to the regular power connection. If the mains power fails, the battery automatically detects this and switches to backup power. This means devices connected to the backup power connection are always powered.

The battery can easily be expanded to power two or three devices, even at a later date. Because we manage each cell block individually and utilize it optimally, devices installed later are not affected by older batteries whose capacity has diminished due to natural aging. You can always utilize the full capacity of each device.

Not in the standard application, as this provides "zero control" of the battery, meaning no power consumption and no feed-in to the public grid. However, the battery does support Modbus RTU and Modbus TCP/IP. Technically savvy customers can therefore control the battery according to their own requirements via an external control unit, provided they program it accordingly.

Your balancing meter from the energy supplier

The netting meter measures consumption and return on all three phases and offsets these against each other.

For example: the extra power taken from phase 1 is offset against the excess and fed-in energy from phase 2.

(In the example above, the installed SAX Home would supply energy on phase 2, which is, however, used by a consumer on phase 1.)

In terms of figures, you do not “lose” any of the solar power you generate yourself and you actually only pay for the consumption that exceeds this.

Only in the event of an emergency power outage should a single-phase inverter be connected to the same phase as the SAX Home battery. This allows the SAX to simulate a grid connection for the inverter, and the inverter will also start in emergency power mode (a grid disconnect switch is required). This allows the loads to be operated and the SAX battery to be charged.

(Inverters from 2018 onwards are required due to communication through frequency increase.)

Installing the battery is very simple: mount the device, install the smart meter in the switch box, connect the battery, switch on – done.

SAX Power performs parameterization at the factory. If necessary, the electrician can pre-adjust this using SAX Power's software. No parameterization or further programming is required on-site during installation. Depending on the situation and the customer's requirements, communication between the battery and the smart meter can be via cable or LORA radio, and the battery's power connection can be via cable or plug-in (Wieland socket). LAN connection is possible via LAN cable, PowerLAN, receiver, etc.

Using a SAX Power winch, one-person installation is possible, eliminating the need to lift the battery manually. In addition to wall mounting, up to three devices can also be mounted on the freestanding SAX stands.

All three phases must be connected in the same orientation. For the reverse current transformers, all three transformers must also be installed in the same orientation. Any drawing errors will be corrected by the smart meter.

21 (+) and 22 (−). Simple telephone cable (8 wires), of which we only need two. No clamp is needed for the smart meter (insert the cable, tighten the screw, and you're done).

4 mm² is sufficient (protected up to 25 A), as the battery switches off at > 20 A.

Not at all. This is prescribed by standards, but we don't use it.

This complies with the standard and is therefore safe. The fuses are 16A, ensuring trouble-free operation even during continuous use.

One battery acts as the master, the others as slaves. This means all four cables are easily connected via a single connector, as the housing currently only allows for two poles.

The battery can be wall-mounted, provided it is strong enough to support the load. Otherwise, we offer a stand that can hold up to three batteries. The stand measures approximately 35cm x 70cm x 180cm.

No, the SAX Home battery is not suitable for outdoor use and is certified according to IP30.

Not necessarily, because there are several ways to connect the battery. The power connection can be via a dedicated cable or a wall socket; communication between the battery and the smart meter can be via cable or wireless. This leads to three useful installation methods:

1. In the standard installation, a power cable and a cable for communication with the smart meter run to the battery – in this case, it is useful if the battery is placed near the meter box.
2. With the wireless installation, communication between the battery and the smart meter is wireless, so no communication cable is required, only a power cable.
3. With the Premium Plug-in system, the battery is connected to any electrical outlet in the house (this must be replaced with a secured outlet) and communication takes place wirelessly. In this version, the installation location is independent of the meter box; the battery can also be placed in a living room, for example. This doesn't pose a noise problem, as the high efficiency generates very little heat and requires no cooling – only two fans are provided.

With the Premium Plug-in installation, the battery is simply connected to any electrical outlet in the home, and communication with the smart meter is wireless. This makes battery placement very flexible.

The main advantages:

• Flexible placement – the battery can be installed almost anywhere in the home.
• Ideal for existing PV installations – especially suitable for users who already have a PV system but do not have a cable connection available.
• Cost savings – no cutting or demolition work is required to lay additional power cables.
• Easy installation – you only need to replace the existing Schuko socket with a secured Wieland socket.

A normal household socket has a power limitation of 16A. Therefore, the battery power output is limited to this capacity when connected via a plug-in system (this is 20A when connected via cable). A protected socket, a so-called Wieland socket.

Yes, an internet connection is required for the battery to connect to the web server. The battery has a LAN connection available. If a LAN cable cannot be laid to the router or switch, you can use Powerline (internet via the wall socket) or from a repeater (receives the home WLAN and has a LAN connection).

The standard installation includes a smart meter installed in the meter box behind the electricity meter. The battery is connected to the smart meter via a communication cable (e.g., RS485 or similar). The battery is also connected to a single-phase power cable and to the internet via a LAN cable.

No, the battery is AC-coupled. Therefore, a PV inverter is always required. The battery is charged with AC power and also supplies AC power to the home grid.

SAX batteries can be easily integrated into existing solar systems, even if batteries from other manufacturers are already present. There are two options for prioritizing batteries:

• Variant 1: The SAX battery is prioritized. This means it is fully charged and then discharged first. Only when the SAX battery's capacity or power is insufficient will the existing battery be called upon.
  
• Variant 2: The existing battery is prioritized. It is charged and discharged first. The SAX battery is only activated when the existing battery can no longer provide sufficient capacity or power.

In this way, the extension can be flexibly tailored to the specific situation.

The wallbox must be programmed as the master, as the battery in a smart home doesn't take over the control function. For safety, it's recommended that the battery be controlled via the smart meter. The wallbox can also provide additional battery control, for example, by setting thresholds for charging and discharging capacity or by reading the charge status and power.

For communication with the wallbox, the battery supports the protocols Modbus RTU, Modbus TCP/IP and Modbus UDPThese are described in detail in the manual.

Installing the battery is simple: mount the device, place the smart meter in the meter box, connect the battery and switch it on – you're done.

The basic configuration is usually preconfigured. If necessary, an electrician can make adjustments using the accompanying software. Additional parameter settings or on-site programming are usually not necessary. Depending on the situation and the customer's requirements, communication between the battery and the smart meter can be via cable or wireless LORA connection. The power connection can be either wired or via a plug-in solution (protected socket, so-called Wieland socket) can be achieved. A LAN cable, PowerLAN, or a receiver can be used for the LAN connection.

With a suitable lifting device, installation can be carried out by a single person, eliminating the need to lift the battery manually. In addition to wall mounting, it's also possible to place up to three batteries on a freestanding stand.

The three phases must be connected with the same orientation. When using arc current transformers, it is important that all three transformers are also installed with the same orientation. Any drawing errors will be automatically corrected by the smart meter.

A simple 8-wire telephone cable is used for the connection, of which only two are needed: terminals 21 (+) and 22 (–). With the smart meter, no additional terminal is needed – the cable is inserted and the screw is tightened, and that's it.

A cable cross-section of 4 mm² is sufficient, as it is protected up to 25 A. The battery also switches itself off automatically at currents above 20 A.

The logical interface does not need to be connected. It is required by law, but not used in this system.

No, that's not a problem. The load complies with the applicable standard. Cables with a cross-section of 1.5 mm² are generally suitable for 16 A, and the fuse is also rated for 16 A. Therefore, continuous operation at this load is technically permitted.

In a three-battery configuration, one device acts as the master, while the other two function as slaves. All four cables are connected via a single common connector, as there is only room for two poles in the housing.