DEYE SUN-20K hybrid 3-phase inverter 20 kW (SM2)

The SUN-20K belongs to the top-end DEYE SM2 generation series for low-voltage battery systems of 40–60 V. In the Czech Republic it holds the legally valid certificate SZU-B-01549-25 (Strojírenský zkušební ústav – Engineering Test Institute, 19/8/2025) and may be permanently connected to the distribution grid under the rules in force since 1/1/2025.

Asymmetric three-phase output of up to 10 kW per phase is the main advantage for households where loads are not evenly distributed across the phases. The inverter automatically compensates for a shortfall on a loaded phase and does not load the free phases. For short peaks it handles 100% overload for 10 seconds — enough to start a compressor, pump or generator without difficulty.

Two independent MPPT trackers (160–650 V) let you connect panels on differently oriented roofs without losing output. Maximum PV input power is 32 kW, so it pays to install a larger array — all the surplus then goes to the battery or is sold to the grid.

A high charge/discharge current of 350 A combined with a voltage range of 40–60 V suits a 15S or 16S battery system. Communication with the BMS over CAN or RS-485 — the inverter is fully compatible with BAKOM battery packs (both 15S and 16S).

Smart Load function — a dedicated input/output to which you can connect a generator, a string inverter or an electric water heater. It works much like a power diverter (wattrouter): surplus electricity is intelligently redirected to another load instead of the grid.

Monitoring via the Solarman platform (Wi-Fi, Ethernet or LTE dongle). IP65 protection and an operating range of −40 °C to +60 °C allow installation directly outdoors, with no need for a plant room. Smart air cooling keeps noise below 60 dB.

10-year warranty — the first 5 years cover all parts and labour, the second 5 years cover all parts except the LCD display and fan, excluding labour. The package includes a wall bracket, 4× wall plugs, 3× current sensors 100 A/50 mA, a lead-acid battery temperature sensor and a Wi-Fi dongle.