€1,033 Tax excluded
ESI 4K-S1 is a 4 kW single-phase HV hybrid inverter with 2 MPPT inputs (85-520 V, 16 A per input) and a backup output with 10 ms switchover. It needs a high-voltage battery: the manufacturer specifies SOFAR BTS 5K modules (350-435 V, 20 A charge and discharge), which are not included. Ingress protection IP65, weight 26 kg.
ESI 4K-S1 is a 4 kW single-phase high-voltage (HV) hybrid inverter with two MPPT inputs. It can be stacked on SOFAR BTS 5K battery modules or installed separately, and combines PV conversion, battery charging, the grid connection and the backup output in one unit.
The inverter requires a high-voltage (HV) battery. According to the manufacturer documentation, this system uses SOFAR BTS 5K LiFePO4 modules of 5.12 kWh, 1 to 6 per inverter. The battery is not included in this product. The inverter can also run without a battery, which can be added later.
The backup output supplies essential loads during a grid outage, with a power equal to the rated power and a peak of 6000 VA for 60 s. The PV inputs accept high-current modules (16 A per MPPT, short-circuit current 22.5 A) and the recommended PV power is up to 8000 Wp. Up to 6 inverters can operate in parallel, and the integrated multi-function EMS optimises self-consumption.
Interfaces: CAN, RS485 and Wi-Fi, optional 4G or LAN, with an LCD and an app. Protections: DC switch, PV and battery reverse polarity, output short circuit, overcurrent and overvoltage, insulation monitoring, residual current, anti-islanding and type II surge protection on PV and AC. The inverter is transformerless with natural cooling.
| Recommended max. PV power | 8000 Wp |
|---|---|
| Max. PV input voltage | 550 V |
| Start-up voltage | 100 V |
| Rated input voltage | 360 V |
| MPPT voltage range | 85-520 V |
| Number of MPPT | 2 |
| Max. strings per MPPT | 1/1 |
| Max. PV input current per MPPT | 16/16 A |
| Max. PV short-circuit current (Isc) | 22.5/22.5 A |
| Battery voltage range | 350-435 V |
| Number of battery input channels | 2 |
| Max. charging power | 4 kW |
| Max. discharging power | 4 kW |
| Max. charging current | 20 A |
| Max. discharging current | 20 A |
| Battery type | Lithium-ion |
| BMS communication | CAN |
| Backup voltage and frequency | L+N+PE, 220/230/240 V, 50/60 Hz |
| Rated backup power | 4 kW |
| Rated backup current (220/230/240 V) | 18.2/17.4/16.7 A |
| Max. backup apparent power | 4 kVA |
| Peak backup apparent power | 6000 VA, 60 s |
| Switching time | 10 ms |
| Rated grid power | 4 kW |
| Max. grid apparent power | 4.4 kVA |
| Max. grid output current (220/230/240 V) | 20.0/19.1/18.3 A |
| Max. AC input current (220/230/240 V) | 36.4/34.8/33.3 A |
| Power factor | 0.8 lagging - 0.8 leading |
| Max. MPPT efficiency | 99.9 % |
| Max. efficiency | 97.7 % |
| European efficiency | 97.0 % |
| Battery-AC efficiency, charging/discharging | 97 % |
| Standby self-consumption | under 10 W |
| Ingress protection | IP65 |
| Operating temperature range | -10 ... 50 °C (derating above 45 °C) |
| Relative humidity | 5-95 % |
| Dimensions (W x H x D) | 708 x 410 x 170 mm |
| Cooling | natural |
| Weight | 26 kg |
| Communication | CAN, RS485, Wi-Fi; optional 4G or LAN |
We took these technical data from the manufacturer’s datasheet; transcription errors are possible. For 100% accuracy, please consult the attached datasheet.
Compatibility is calculated automatically from the manufacturers’ technical data and is for information only. For complex systems, we recommend having the configuration checked by a consultant before ordering. Details in the Terms and conditions
