REFUsol 20K-3T
Flexible for commercial rooftops with several roof areas
- AC power
- 20 kW
- MPPTs
- 3
- max. efficiency
- 98.6 %
At a glance
1,100 V
Max. DC voltage
30 kWp
Max. recommended PV power
DC/AC ratio up to 150 %
up to 45 °C
Full AC power
Derating above this temperature
98.2 %
European efficiency
IP65
Protection rating
10 years
Warranty
Your benefit as …
Operators & investors
Real-time monitoring with REFUview
REFUview shows the status, output and yield of your PV plant in real time, on your computer and on your smartphone. Spot deviations early and protect your yield.
Data hosting in Germany
Your plant data is hosted and processed in Germany. This makes data protection and data sovereignty easier, especially for operators of critical infrastructure.
Technical support from Germany
For questions about operation, faults or firmware updates, you can reach our technical support in Germany, personally and without detours.
EPCs & general contractors
Datasheets, certificates and manuals in the download centre
Datasheets, unit certificates, declarations of conformity and manuals are all in one place in the download centre, always in the current version.
Personal contacts in sales and engineering
For system design, quotations and detailed technical questions, you talk directly to our sales team and our engineers, including for large solar parks.
Scalable with REFUlink and REFUview
REFUlink connects up to 60 inverters to the control room and the grid operator, while REFUview brings all operating data together. The system grows with your plant.
Installers & electrical contractors
Easy commissioning
Many models can be set up via app over Bluetooth directly at the inverter. This saves time when commissioning on commercial rooftops.
Technical support from Germany
For questions about installation, settings or error messages, you can reach our technical support in Germany, personally and without detours.
Fits new and existing systems
REFUsol inverters can be integrated into new and existing PV plants, and via REFUlink also together with older generations of REFU inverters.
Technical data
Datasheet (PDF)DC data
| Max. recommended PV power | 30 kWp |
|---|---|
| Max. input voltage | 1,100 V |
| Rated input voltage | 620 V |
| Start-up input voltage | 200 V |
| Operating voltage range | 180–1,000 V |
| MPPT voltage range | 480–850 V |
| Number of independent MPPTs | 3 |
| DC inputs per MPPT | 2 |
|---|---|
| Max. current per MPPT | 40 A |
| Max. short-circuit current per MPPT | 50 A |
| Max. power per MPPT | 20 kW |
| DC connection | MC4 |
| Max. DC/AC ratio | 150 % |
AC data
| Rated AC power (active power) | 20 kW |
|---|---|
| Max. AC apparent power | 22 kVA |
| Max. output current | 33.3 A |
| Nominal grid voltage | 3P/N/PE: 230/400 V |
| Grid voltage range | 310–480 V |
| Nominal grid frequency | 50 / 60 Hz |
| Grid frequency range | 45–55 / 55–65 Hz |
|---|---|
| Active power adjustable range | 0–100 % |
| Total harmonic distortion (THDi) | < 3 % |
| Power factor adjustable range | 1 (0.8 inductive … 0.8 capacitive) |
| AC connection | OT (M6) |
| AC overload capability | 110 % |
Efficiency
| Max. efficiency | 98.6 % |
|---|
| European efficiency | 98.2 % |
|---|
Protection
| DC switch | integrated |
|---|---|
| String monitoring | per MPPT |
| Safety protection | Anti-islanding, DC reverse polarity protection, Reverse current protection, Ground fault monitoring, Residual current monitoring (RCMU), Overtemperature protection, Overvoltage protection, Overcurrent protection |
| Protection class | I |
| Overvoltage category DC | II |
| Overvoltage category AC | III |
|---|---|
| Surge protection DC | Type II (standard), Type I + II (optional) |
| Surge protection AC | Type II |
| AFCI (arc fault detection) | Optional |
Communication
| RS485 | Yes |
|---|
| USB | Yes |
|---|
General data
| Min. ambient temperature | −30 °C |
|---|---|
| Max. ambient temperature | 60 °C |
| Derating from | 45 °C |
| Night-time self-consumption | < 1 W |
| Topology | transformerless |
| Protection rating | IP65 |
| Permissible humidity range | 0–100 % |
| Max. operating altitude | 4,000 m |
|---|---|
| Weight | 36 kg |
| Cooling | Active |
| Display and operation | LCD / Bluetooth (BLE) / App |
| Noise level | < 60 dB(A) |
| Dimensions (H × W × D) | 480 × 585 × 220 mm |
| Warranty | 10 years |
Item no. 853P020Data as of: 28 September 2026WEEE-Reg.-Nr. DE35952985Subject to technical changes
Downloads
- Datasheet – REFUsol 20K-3TEnglish, German, As of 05/2026, Version V01, PDF, 3.3 MB
- Manual – REFUsol 20K-3T, 25K-3T, 33K-3T, 50K-4TEnglish, German, As of 03/2025, Version V02, PDF, 6.7 MB
- Unit certificate VDE-AR-N 4110 – REFUsol 20K-3T, 25K-3T, 33K-3T, 50K-4TGerman and English, As of 10/2024, valid until 16.03.2028, PDF, 383 KB · 2622/0564-E2-M1-CER
- Warranty conditions for photovoltaic inverters from 01.07.2026German and English, valid from 01.07.2026, Version V1, PDF, 171 KB
Discuss your project
Which model suits your commercial or industrial system? We advise you personally, directly with our engineers.
Or directly+49 7121 145 1888info@refu.com
Request a project