Deye SUN-12K-SG02LP1-EU-AM3 (12 kW) - single-phase hybrid inverter

When twelve kilowatts on a single phase is the right call

Twelve kilowatts from a single-phase supply is the scenario where heavy consumption already exists and a three-phase line does not and will not: the classic case in older villages and residential districts where the utility offers only one phase. An inverter of this size carries a house consuming 25 to 35 kWh a day in full: several air conditioners, a borehole pump, a resistive water heater, washing and dishwashing machines, an oven and a workshop with power tools can all run together without hitting the ceiling. It also suits light production on a single phase: a bakery with two ovens, a joinery shop, a car wash, a service station with a compressor and a lift. If a three-phase supply is available, however, buying a single-phase 12 kW unit makes no sense: the three-phase SUN-12K-SG04LP3-EU (item 2054) delivers the same power spread across three phases, with lower cable currents and correct supply for three-phase motors. And an honest limitation: twelve single-phase kilowatts demand a matching service connection and wiring, so it is worth reading what your supply contract actually allows before buying.

54.6 A at the output: the question to settle before installation

Rated output current is 54.6 A at 220 V and 52.2 A at 230 V, with a maximum reaching 60 A — these are no longer domestic figures and the wiring has to be calculated specifically for them. The cable from inverter to backup board should be 16 mm² copper with a 63 A breaker, and the condition of the building's own service cable must be checked: in older properties the aluminium feeder simply will not carry that power without heating up. Grid pass-through here is 60 A, about 13 kW flowing through the inverter while mains power is present, so from the house's point of view there is almost no restriction — one more reason to bring the power side up to a decent standard. It is also worth calculating the consumption your contract permits: if the service is limited to 25 or 32 A, the inverter will not be able to draw its twelve kilowatts from the grid, even though it will deliver them in full from panels and battery. An audit of the power side is the cheapest way to avoid an unpleasant surprise after commissioning.

Three 26 A MPPTs and an array twice the inverter rating

The photovoltaic side is substantial: three independent trackers with two strings each, 26 A of operating current per tracker and short-circuit current up to 44 A. Six strings allow panels to follow any awkward configuration — east, west and south separately, the house roof plus the garage plus a canopy — with each group working at its own maximum power point rather than dragging the others down. Rated array power is 19 200 W, yet up to 24 000 W may be connected, exactly twice the inverter's output rating. That degree of oversizing is not meant for summer but for winter and overcast weather: a 24 kW array in December yields the same 4 to 6 kW that half that size produces in June, while the midday surplus in the warm season is simply clipped. The tracker window spans 150 to 425 V against a 500 V maximum with a 125 V start-up; strings are best sized near the rated 370 V where conversion is most efficient, without forgetting how open-circuit voltage rises in frost.

A 250 A battery channel and galvanic isolation

Battery charge and discharge current is 250 A, roughly 12.8 kW at 51.2 V, meaning the inverter can deliver its full output from storage alone, with no sun and no grid. For that to be real the battery bank must sustain such a current: a single SE-F5 module (item 1944) rated 120 A continuous covers less than half, so the practical configuration is two or three modules in parallel or one large block such as the RW-F16 (item 1931). At these currents the battery power path becomes a project in itself: 50 to 70 mm² cable, a fuse or battery breaker rated 250 to 300 A, and identical lengths and cross-sections for every module lead — otherwise the current divides unevenly. The topology is mixed: the PV channel is transformerless while the battery channel is galvanically isolated, which noticeably improves safety when working with high currents at low voltage. The BMS link runs over RS485 or CAN with protocol self-adaptation, so the inverter reads the actual state of each module and never lets the bank leave its safe window.

A 24 kW ten-second peak and working with a generator

Apparent power is 13 200 VA, and in island mode the inverter holds double its nominal rating — about 24 kW for ten seconds. For a site with motors that is the decisive specification: a workshop compressor, a submersible pump, a woodworking machine and an industrial chiller starting together produce an inrush peak no battery could absorb without that reserve on the inverter side. A generator input is provided and it is no formality here: with twelve kilowatts of consumption the storage empties quickly, so during long winter outages the generator becomes the main source and the inverter acts as a buffer that smooths the starts and keeps the set off idle running. Generator charging is configurable by time and current: charging can be allowed only in set hours, or the current limited so the set is not overloaded. A practical note: a generator for this inverter should be at least 8 to 10 kVA with a clean waveform, otherwise synchronisation either fails or comes with voltage dips.

Cooling, noise and what the installation site must offer

Cooling in this revision is intelligent, but the noise level is quoted at up to 45 dB — noticeably more than on smaller models, and a direct consequence of twelve kilowatts that have to be cooled. Plan the location accordingly: a boiler room, a technical room, a garage or a hallway will do, while a wall shared with a bedroom or a nursery becomes a permanent source of complaint. The 420 by 670 by 233 mm enclosure weighs 35.6 kg and goes on solid masonry; lifting it takes two people, preferably three, with the mounting rail fixed first. The operating range is -40 to +60 °C with derating beginning above +45 °C, protection is IP65, humidity up to 100 % non-condensing and altitude up to 2000 m, so almost any conditions are tolerated — yet sustained full-power operation in a hot closed room will still cost output. The integrated DC isolator saves a separate box, MC4 connectors simplify string wiring, and Wi-Fi is built in here, so no external communication dongle is required.

How it differs from its neighbours in this catalogue

Its closest relative is the SUN-10K-SG02LP1-EU-AM3 (item 2059): same enclosure, same weight, the same three 26 A trackers, but 10 kW instead of 12, a battery current of 220 A instead of 250 and an array limit of 20 kW instead of 24. If your maximum simultaneous load stays under nine kilowatts the ten-kilowatt unit covers it with margin, while the twelve is for sites where everything really does switch on at once. The larger SUN-16K-SG01LP1-EU (item 2055) goes further — 16 kW, 290 A of battery current and 100 A of grid transit — but it is physically bigger, 13 kg heavier and demands an even more serious power installation. The smaller SUN-8K-SG01LP1-EU (item 2047) with two trackers and 190 A of battery current is cheaper as a system and sufficient for most private houses. And the key comparison: at identical power, the three-phase SUN-12K-SG04LP3-EU (item 2054) spreads the same 12 kW across three phases, so wherever a three-phase supply exists it is the technically sounder choice over this single-phase model.

Send us a single-line diagram of your supply, or simply a photo of the distribution board, and we will tell you whether your power installation can carry twelve single-phase kilowatts and what should be upgraded.