Sunways STH-12KTL Asymmetric Hybrid Inverter 12kW - 3-phase
Payment and delivery
Payment and delivery
Payment
You can pay for your order by bank transfer in advance, in Hungarian Forints or Euros. Cash on delivery is available for orders up to HUF 500,000, with a handling fee of HUF 4,990. For orders over HUF 500,000, only bank transfer in advance is possible. The proforma invoice will be sent to you by e-mail, containing the necessary bank transfer details.
Delivery
We deliver your orders throughout Hungary with the help of our reliable logistics partners or our own transport. Personal pickup is possible by prior arrangement. Shipping costs are determined based on the size, weight, and type of the ordered product:
- Small package: HUF 3,790
- Large package: HUF 6,490
- Heat pump: free shipping
- Solar panel and battery: individual shipping fee (based on size, weight, and quantity)
Product description
Product description
The Sunways STH series of three-phase, high-voltage (HV) hybrid inverters are available in a power range of 4 to 12 kW, for residential and small commercial solar systems. These devices manage solar production, grid connection, and lithium battery energy storage within one system, enabling increased self-consumption and backup power supply.
The inverters feature two MPPT inputs, allowing flexible adaptation to solar arrays with different orientations or string configurations. The 140–750 V battery voltage range ensures broad compatibility with high-voltage lithium batteries, while the system provides efficient charging and discharging operations.
A key advantage of the STH series is its stable and fast backup operation. In the event of a power outage, the inverter switches to off-grid mode in under 10 ms and can handle temporary overloads of up to 200%. The backup output on a selected phase can support up to 125% load, which facilitates the operation of consumers with higher starting currents.
The devices support limited phase-by-phase load imbalance: a maximum of 110% output power is allowed on one phase in both grid-connected and backup modes, while the load on the other two phases remains regulated. This allows for handling minor inconsistencies in residential consumption without compromising system stability.
System monitoring is available via an OLED display and a mobile application. The IP65 rating makes it suitable for indoor and outdoor installation, and natural cooling ensures quiet operation.
- 4–12 kW power range, 3-phase
- Hybrid operation: PV + battery + grid
- High-voltage battery compatibility (140–750 V)
- 2 MPPT inputs for flexible PV design
- <10 ms switchover to off-grid mode
- Up to 200% backup overload (60 s)
- Limited phase-by-phase load imbalance (max. 110%)
- IP65 protection, outdoor installation
- OLED display and app-based monitoring
| Teljesítmény | 12 kW |
|---|---|
| Típus | Asymmetric Hybrid Inverter |
| Akkumulátor-kompatibilitás | Yes (Li-ion, 140–750 V) |
| MPPT-k száma | 2 |
| Max. hatásfok | 98.2% |
| Garancia | 10 years |
| Max. PV feszültség | 1000 V |
| MPP tartomány | 200–850 V |
| DC/AC túlméretezési arány | 1.6 |
| EPS / Backup kimenet | Yes |
| Max. backup teljesítmény | 13.2 kW |
| IP védelem | IP65 |
| Méret | 550 × 410 × 175 mm |
| Tömeg | 28 kg |
Do you have a question?
See our most frequently asked questions, or contact us.
How do I choose the right inverter?
How do I choose the right inverter?
When selecting an inverter, the most important aspects are the system size, type, and future expandability.
First, the inverter must be matched to the power and voltage range of the solar panels, and it must also be considered whether the system will be connected to a single-phase or three-phase grid. It is also worth thinking ahead about whether you want to add a battery later, as this requires a suitable (hybrid) inverter.
For three-phase systems, a significant difference exists between symmetric and asymmetric operation. A symmetric inverter distributes power evenly among the phases, while an asymmetric inverter can regulate it differently per phase, according to actual consumption.
The latter solution is more efficient in most households, as it better adapts to daily consumption patterns and can reduce the amount of energy drawn from the grid.
When is it worth choosing a hybrid inverter?
When is it worth choosing a hybrid inverter?
It is worth choosing a hybrid inverter if you are thinking about developing the system in the long term.
This type is an ideal solution if you want to build a battery energy storage system in the future, or if it is important for you to have power supply even in the event of a power outage (with a backup function).
Although hybrid inverters initially represent a higher investment, they are more flexible and allow for later expansion of the system without the need for a complete inverter replacement.
Therefore, it is especially recommended for those who want to optimize their energy consumption and increase energy independence in the long term.
What happens in a power outage?
What happens in a power outage?
In the event of a power outage, whether there will be electricity depends on the inverter type and the system's design.
Traditional grid-tied (on-grid) inverters automatically shut down in such cases and therefore do not provide power for safety reasons, even if the solar panels are generating.
Hybrid inverters – with an appropriate battery – are capable of off-grid (backup) operation, but this is not always a basic function. For many systems, a separate backup box or EPS (Emergency Power Supply) output/add-on is required for the system to operate during a power outage.
With such a design, the inverter disconnects itself from the grid and continues to supply designated consumers (e.g., lighting, refrigerator, essential devices) with the help of the battery.
Therefore, if continuous power supply is important, it is worth checking during the planning phase whether the given inverter supports the backup function and if an additional unit is needed.
What is the warranty for inverters?
What is the warranty for inverters?
Inverter warranties vary depending on the manufacturer and model.
In most cases, a 5-10 year manufacturer's warranty applies, which can be extended with some manufacturers through registration or a separate extension.
The exact warranty period and conditions are specified for each product, allowing them to be clearly checked before purchase.
If you are unsure about your choice, we can help you find an inverter that provides a reliable long-term solution.
What happens if the inverter fails?
What happens if the inverter fails?
If the inverter malfunctions, the first step is to accurately identify the fault.
In many cases, the problem does not originate from the inverter itself, but can be attributed to a configuration, communication, or system connection error, so it is worth checking this first.
If it is a genuine device fault, repair or replacement will be carried out with the involvement of the manufacturer or an official service partner, either within or outside the warranty period.
If necessary, we can assist with fault investigation and initiating warranty claims to ensure a quick and smooth process.
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