EG4 FlexBOSS21 Hybrid Solar Inverter | 21kW PV / 16kW AC | Split-Phase | 4-MPPT | Scalable | Remote Wi-Fi Monitoring
EG4 FlexBOSS21 Hybrid Solar Inverter | 21kW PV / 16kW AC | Split-Phase | 4-MPPT | Scalable | Remote Wi-Fi Monitoring
SKU: INV027
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- Price: $4,199.00
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PRODUCT DESCRIPTION
Description
The EG4 FlexBOSS21 is a high-capacity split-phase hybrid inverter engineered for advanced residential and commercial energy systems. With 12kW output and up to 21,000W of PV input, it delivers powerful performance in both on-grid and off-grid setups. Equipped with 3 MPPTs for up to 5 strings, 90A grid feed-through at 120/240VAC, and seamless integration with the EG4 GridBOSS MID gateway, it offers superior flexibility, smart load management, AC coupling, and generator support. Safety features include rapid shutdown, ground fault and arc fault protection, and industry-leading certifications. With remote monitoring, Wi-Fi connectivity, and mobile alerts, the FlexBOSS21 combines efficiency, scalability, and cutting-edge technology to power modern energy systems with confidence.
Specifications
Inverter Specifications
| Category | Specification |
|---|---|
| Nominal AC Voltage | 120/240VAC | 120/208VAC (L1/L2/N required) |
| Frequency | 60 Hz (Default) | 50 Hz |
| Max AC Current | 50A @ 240V | 57.7A @ 208V |
| Max AC Input Power | 12,000W |
| Max AC Bypass | 90A |
| Operating Voltage Range | 180 – 270VAC |
| Output Voltage | 120/240VAC | 120/208VAC (L1/L2/N required) |
| Max Output Current | 66.7A |
| Output Frequency | 60 Hz (Default) | 50 Hz |
| Nominal Output Power (Without PV) | 12,000W @ 240V | 12,000W @ 208V |
| Nominal Output Power (With PV) | 16,000W @ 240V | 13,800W @ 208V |
| Power Factor | 0.99 (Full Load) |
| Reactive Power Adjustment Range | -0.8 to 0.8 (Leading Adjustable) |
| Total Harmonic Distortion (THD) | <5% (Full Load) |
| Transfer Time | 20ms (Default) | 10ms (Configurable) | 20ms (Parallel) |
| Rated Output Current | 50A @ 240V | 57.7A @ 208V |
| Nominal Output Voltage | 120/240VAC | 120/208VAC |
| Rated Output Power | 12,000W @ 240VAC | 12,000W @ 208VAC |
| Peak Power | 24,000W (0.5 sec) | 18,000W (1 sec) | 15,000W (6 min) | 13,200W (12 min) |
| Operating Frequency | 60 Hz (Default) | 50 Hz |
| Total Harmonic Distortion Voltage | <5% |
| Transfer Time (Output) | 20ms (Default) | 10ms (Configurable) | 20ms (Parallel) |
| Number of MPPTs | 3 |
| Inputs per MPPT | 2 (MPPT 1) | 2 (MPPT 2) | 1 (MPPT 3) |
| Max Usable Input Current | 26A (MPPT 1) | 26A (MPPT 2) | 15A (MPPT 3) |
| Max Short Circuit Input Current | 31A (MPPT 1) | 31A (MPPT 2) | 19A (MPPT 3) |
| DC Input Voltage Range | 100 – 600VDC |
| Unit Start-Up Voltage | 100VDC |
| MPPT Operating Voltage Range | 120 – 440VDC |
| Nominal MPPT Voltage | 360VDC |
| Max Utilized PV Array Power | 21,000W |
| Max Recommended PV Input | 25,000W |
| Maximum Efficiency | 97% (PV → Grid) | 94.5% (PV → Battery) | 94% (Battery → Grid) |
| Idle Consumption | <65W |
| Nominal Battery Voltage | 48VDC |
| Battery Voltage Range | 40 – 60VDC |
| Max Charge / Discharge Power | 12,000W |
| Recommended Battery Capacity | >300Ah per inverter |
| Operating / Storage Temperature | -13°F – 140°F (-25°C – 60°C) |
| Operating Altitude | <6,561 ft (2000 m) |
| Relative Humidity | 0 – 100% |
| Typical Noise Emission | <50 dB @ 3 ft |
| Design Topology | High-Frequency / Transformerless |
| Protection Rating | IP65 / NEMA 4X |
| Communications | RS485 / CANBus / WiFi |
| Max Parallel Connections | 16 |
| Weight | 88 lbs (40 kg) |
| Dimensions (H × W × D) | 30.5 × 22.3 × 11.3 in (775 × 567 × 287 mm) |
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