Weco TH 20kW20kW three-phase high-voltage hybrid inverter

Overview

The TH 20kW is the largest model of the TH 8–20kW range: 20kW and 22.2kVA on a 400V three-phase grid, with two MPP trackers rated 25A and two strings each, for up to 30kW of PV. Battery charge and discharge current is 50A with WeCo high-voltage LFP storage. The backup output supplies 20kW, or 30kVA for 10 seconds, and grid bypass reaches 50A.

• 8–20kW three-phase, 400V output
• Battery 135–750V, 50A charge/discharge
• 2 MPPT, 1000V max., up to 30kW PV
• 150% backup overload for 10s
• Integrated zero-export control
• IP66, 20kg, wall mounting

How it works

The TH 8–20kW series is a transformerless three-phase hybrid inverter for high-voltage WeCo LFP batteries in the 135–750V range, charged and discharged at up to 50A over CAN. On the PV side two MPP trackers work from 140 to 850V with 1000V maximum input and 160V start-up; the 8 and 10kW models take one string per tracker at 20A, the 12 and 15kW two strings at 20A, and the 18 and 20kW two strings at 25A.

PV array power reaches twice the rated output on the 8, 10 and 12kW models: 16kW, 20kW and 24kW, while the 15kW model takes 24kW and the 18 and 20kW models 30kW. The backup output carries full rated power on 400V three-phase and can deliver 150% for 10 seconds, switching over within 20ms. Grid bypass ranges from 23.2A on the 8kW to 50A on the 18 and 20kW models.

Key features

Efficiency reaches 98.4% maximum and 97.5% European, with 99.9% MPPT efficiency. Protection includes PV isolator, string and battery reverse polarity protection, an all-pole sensitive residual current monitoring unit, anti-islanding and AC overcurrent, short-circuit and overvoltage protection, with overvoltage category III on AC and II on DC. Power control and zero-export control are integrated, using an RS485 grid meter.

Installation and compatibility

The TH is wall-mounted, weighs 20kg and measures 535×465×215mm, with an IP66 enclosure behind a glass front and forced-air cooling that switches on when needed. It operates from −25 to +60°C and up to 4000m, with derating above 3000m, and standby consumption on-grid is below 25W. The datasheet lists EN 62109-1/-2 and EN 62477-1 for safety and IEC 61000-6-1 to -4 for EMC; batteries must be WeCo LFP models.

Monitoring and settings

Monitoring and settings run through a Wi-Fi logger and WeCo's NooR app, with LED status indication on the unit. The inverter warranty is five years, extendable to ten when the inverter is connected to a WeCo lithium storage system and registered on WeCo's platform.

Questions and answers