Tigo Energy 3.8 kW 50A ATS-Compatible String Inverter TSI-3.8K-US

The Tigo Energy EI Inverter 3.8 kW (Compatible with 50A ATS) is a hybrid, grid-interactive inverter with battery support that coordinates solar generation, self-consumption, and backup power. It accepts up to 200% DC oversizing, has 2 MPPTs, and uses a rugged NEMA 4X/IP65 enclosure—great for new PV storage systems or upgrades with Tigo TS4 MLPE and EI/GO batteries.

• 3.8 kW nominal AC power at 240 V (3290 W at 208 V); 16 A max AC output current (grid-tied)
• Backup-ready: up to 25 A max backup output current with GO Battery (300 ms duration); 19 A with EI Battery
• Up to 7.6 kW recommended PV input (STC) with 2 MPPTs; 2 strings per MPPT
• 600 V max DC voltage and wide 80–550 V MPPT operating window; full-load range 150–500 V
• 80 V start voltage and generous string current limits (13.5 A/16.9 A IMP/ISC per MPPT) enable flexible stringing
• Powered by the Tigo Energy Intelligence platform for module-level monitoring, optimization, and rapid shutdown (NEC 690.12)
• Built-in Wi-Fi (optional 4G) and fast, app-guided commissioning
• Listed to UL 1741 / IEEE 1547 and other key grid standards; revenue-grade metering (ANSI C12.20)

Hybrid control for solar storage

Pair with Tigo EI or GO batteries to store extra PV and keep essential loads running during outages. The inverter automatically balances production and consumption to favor self-use while staying grid-compliant.

Flexible DC design, dependable yield

Two independent MPPTs, a 2:1 DC/AC ratio, and broad voltage windows let you mix roof planes, run longer strings, or add modules later without compromising performance.

Outdoor-ready and installer-friendly

The NEMA 4X/IP65 enclosure stands up to the elements for yard or garage installs. Roomy wiring space, quick-start commissioning, and integrated rapid shutdown help speed up installs.

Works with 50A ATS

This 3.8 kW model is compatible with 50 A automatic transfer switches for tidy, code-compliant backup integrations and seamless source switching.

Size

15.8" × 7" × 22"

Weight

32.3 lb

Warranty

152 months