Deye SUN-18K-SG05LP3-EU-SM218kW three-phase low-voltage hybrid inverter, 48V battery

Overview

SUN-18K-SG05LP3-EU-SM2 delivers 18kW rated and 19.8kVA maximum three-phase power with a 48V battery charged and discharged at up to 330A. Two 36A MPP trackers take up to 36kW of PV access power and 28.8kW of input power at up to 800V. The higher battery current calls for 70mm² battery cables on the two battery inputs, and the inverter suits commercial buildings, farms and large homes that rely on low-voltage battery banks.

• 14–20kW three-phase on a 48V battery (40–60V)
• 260–350A charge/discharge, two battery inputs
• 2 MPPT, 36A each, up to 40kW PV access
• 70A grid-to-load pass-through
• 100% unbalanced output, 10 units in parallel
• CEI 0-21, VDE-AR-N 4105, EN 50549 listed

How it works

The 14–20kW SG05LP3 models are three-phase hybrid inverters that run a large PV array, a 48V battery bank, the grid, a backup circuit and a generator. Despite the low battery voltage, they reach up to 350A of charge and discharge current (260A on the 14kW model) through two battery inputs; the battery side is transformer-isolated and the PV side is transformerless. Lithium batteries are charged to the limits reported by their BMS over CAN or RS485.

Two MPP trackers with two strings each accept up to 36A per tracker, 800V maximum and 160–650V in MPPT operation, for up to 40kW of PV access power on the 20kW model. Grid-to-load pass-through is 70A. Off-grid the inverter delivers twice the rated power for 10 seconds, and it can supply fully unbalanced loads with up to 50% of rated power on any phase.

Key features

Battery use follows six programmable time periods, with Selling First, Zero Export to Load or Zero Export to CT as work modes. The GEN port works as a diesel generator input, as a smart load output switched by battery state of charge or voltage, or as an AC-coupling port for existing on-grid inverters. A dry contact (G-start) can start a generator automatically, and up to 10 inverters can be paralleled on-grid or off-grid.

Installation and compatibility

The IP65 unit of 456×750×268.5mm and 51.9kg mounts on a load-bearing, non-flammable wall out of direct sun, rain and snow, with about 50cm free at the sides, above and below and 100cm in front. Deye recommends 100A AC breakers on the grid and backup ports, a DC protection device on the battery line and battery cables of 50mm² (14–16kW) or 70mm² (18–20kW) on M8 terminals.

Export control uses the supplied CT sensor, or a CHNT DTSU666 or Eastron SDM630-Modbus V2 meter on the Meter-485 port. The datasheet lists IEC 61727, IEC 62116, CEI 0-21, EN 50549, NRS 097, RD 140, UNE 217002, OVE-Richtlinie R25, G99 and VDE-AR-N 4105, and Deye publishes country certificates for the series. In Germany the backup function is optional and the backup side may be left unconnected.

Monitoring and settings

Configuration is done on the LCD: battery type and limits, time-of-use periods, work mode, grid code, GEN port use and parallel settings. Remote monitoring runs through Deye Cloud with an optional Wi-Fi logger, and the inverter also offers RS485 and CAN. Operation is possible from -40 to 60°C, with derating above 45°C. The warranty is 5 years, extendable to 10 years depending on the installation country.

Questions and answers