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EG4 FlexBOSS21 Hybrid Inverter

EG4 FlexBOSS21 16kw AC Hybrid Inverter | 48V Split Phase | 21kW PV Input
$3,599.00 - $3,599.00
$3,599.00
$3,599.00 - $3,599.00
$3,599.00
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EG4 FlexBoss21 Manual & Spec Sheet

View Manual HERE
View Spec Sheet HERE

EG4 FlexBOSS21 16kw AC Hybrid Inverter | 48V Split Phase | 21kW PV Input

The EG4 FlexBOSS21 is a split-phase, all-in-one hybrid inverter designed for residential and small commercial applications. With a 21kW usable PV (DC) input, it delivers high power output, providing 12kW of AC power during non-sunlight hours and a full 16kW AC with solar PV input. This powerful and versatile inverter can pass through up to 90 amps of utility power from the grid at 120/240 VAC.

An enhanced version of EG4's flagship 18kPV inverter, the FlexBOSS21 is optimized to work seamlessly with EG4's GridBOSS MID (power gateway). Together, the FlexBOSS21 and GridBOSS reduce installation costs by eliminating unnecessary components and cutting installation time. This combination offers an unmatched solution for customers seeking efficient, cost-effective, and scalable solar power systems.


EG4 FlexBOSS21 Hybrid Inverter Specs & Features


  • PV Input: 21kW max usable, 24kW max input. V3.1
  • Continuous AC Output: 16kW @ 240V, 13.8kW @ 208V
  • Nominal Current: 50A
  • Nominal Output Voltage: 120/240V | 120/208V | 240V
  • Continuous Output Power: 12000VA
  • Dimensions: 30.4×22.3×11.2 in.
  • Weight: 88 lbs
  • Includes: 1 x 90A Breaker (Compatible only with the EG4 FlexBOSS21) & Smart Port Breakers Rated at 30A, 40A, 60A, and 80A.
  • Operate off-grid, with grid support, or sell excess power back to the grid.
  • Supports up to 600V DC, allowing reduced cable sizes.
  • Remote access with Wi-Fi and closed-loop communication with compatible batteries.
  • Includes rapid shutdown, ground fault monitoring, arc-fault protection, and robust safety certifications.


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