EI Inverter (EU)

EI Inverter (EU) is Tigo Energy’s hybrid inverter for the European GO Optimized solar and storage system. The current family includes single-phase 3, 3.7, 5 and 6 kW models and three-phase 6, 10 and 15 kW models. The 3.7 kW single-phase model is the UK version.

Phase schedule	Rated output	Model code
single-phase	3 kW	TSI-3K1D
single-phase, UK-only	3.7 kW	TSI-3.7K1D
single-phase	5 kW	TSI-5K1D
single-phase	6 kW	TSI-6K1D
three-phase	6 kW	TSI-6K3D
three-phase	10 kW	TSI-10K3D
three-phase	15 kW	TSI-15K3D

Solar input ranges

All listed models have two MPPTs. Single-phase maximum PV input runs from 4.5 to 9 kW by model, with a 600 V maximum input and 90 V start voltage. The three-phase models allow 10 to 18 kW, with a 1,000 V maximum and 200 V start voltage. String current and tracker allocation vary by model, especially within the 10 and 15 kW three-phase versions, so the full model code is needed for array design.

Maximum efficiency is 97.6% for the single-phase family and 98.2% for three-phase. The inverter enclosure is rated IP65. Single-phase units weigh 22 kg and three-phase units weigh 34 kg.

Battery and backup

The inverter is designed for Tigo’s GO Battery (EU) and EI Link (EU). Backup changeover is under 0.25 seconds for single-phase and under 2 seconds for three-phase. Backup output, protected circuits, earthing and switching still have to be designed as a complete system.

The family includes G98 and G99 compliance routes, but the applicable UK connection route depends on the exact model and combined generation or storage arrangement. Current device evidence and the relevant DNO determine that route.

The residential warranty term is 152 months, subject to registration within 90 days and other terms, including connectivity conditions for full-duration cover.

Related entries

• Tigo Energy
• G98 notification pathway
• G99 application pathway
• Whole-home backup and changeover