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EG4 FlexBoss21 Hybrid Inverter

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| SKU:

INV027

$4,199.00
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EG4 FlexBoss21 Hybrid Inverter | 16kW Split-Phase

48V Split-Phase Hybrid Inverter/Charger with 21kW PV Input, Scalable up to 16 Units, NEC & CSA Compliant

The EG4 FlexBoss21 is a high-performance hybrid inverter capable of off-grid, grid-tied, and backup operation. With up to 16kW AC output and 21kW solar input across three independent MPPTs, it provides flexible system design and reliable power conversion. Its high-frequency transformerless design maximizes efficiency while closed-loop battery communication optimizes charging and lifespan. Scalable up to 16 units (256kW total), the inverter supports advanced monitoring, fast transfer times, and integration with EG4 48V batteries or other lithium/lead-acid systems.

Key Features:

  • 16kW Split-Phase Hybrid Output: Supports off-grid, grid-tied, and backup power applications.
  • Up to 21kW Solar Input: Three independent MPPTs with 600VDC max input.
  • Transformerless High-Frequency Design: Provides efficient and reliable operation.
  • Parallel Capability: Connect up to 16 units for a total system output of 256kW.
  • Battery & Grid Integration: Works with 48V lithium and lead-acid batteries, with closed-loop communication support.
  • Built-in Rapid Shutdown Compliance: Meets NEC 690.12 & CSA C22.2#330:2017 safety standards.
  • Wi-Fi Monitoring & Remote Adjustments: Integrated plug-in Wi-Fi device for mobile monitoring and control.
  • Fast Transfer Time: 10ms to 20ms automatic switching for uninterrupted power.
  • 10-Year Standard Warranty: Ensures long-term reliability.

Ideal Applications:

  • Off-grid homes and remote installations
  • Backup power for residential and commercial systems
  • Smart grid-interactive solar energy management
  • Scalable hybrid solar power plants

What’s Included:

  • 1 × EG4 FlexBoss21 Hybrid Inverter
  • User manual and installation guide
  • Wi-Fi monitoring plug-in device

Specifications

Parameter Details
Power Output & Input Specifications
Model NumberEG4 FlexBOSS 21
AC Output Voltage120/240VAC (Split-Phase) / 120/208VAC (L1/L2/N)
Nominal Power Output16kW (PV & Battery), 12kW (Battery Only)
Peak Power Output24kW (0.5 sec) / 18kW (1 sec)
Maximum PV Input21kW
Maximum DC Input Voltage600VDC
MPPT Voltage Range120-440VDC
Number of MPPTs3 (2 Inputs per MPPT for MPPT 1 & 2, 1 Input for MPPT 3)
Transfer Time10ms (Configurable) / 20ms (Parallel Mode)
Battery Specifications
Battery Voltage48VDC
Battery Charging Power12kW Max
Battery CompatibilityLead-Acid / Lithium
System Expansion & Performance
Parallel CapabilityUp to 16 Units (256kW Total)
Cooling ConceptForced Air Cooling
Noise Emission<50dB @ 3ft
Environmental & Enclosure Specifications
Enclosure RatingNEMA 4X
Operating Temperature-25°C to 60°C (-13°F to 140°F)
Physical Specifications
Dimensions (H × W × D)30.43" x 22.28" x 11.22"
Weight88 lbs
Certifications & Compliance
CertificationsUL 1741 SA, IEEE 1547, CSA 22.2, NEC 690.12 (RSD), FCC Part 15

Understanding Your Power Needs

Power Calculation Guide

Sizing Metric Formula & Example
Energy Consumption (Wh) Formula: Watts × Hours
Example: 60W × 4 hrs = 240 Wh
Battery Capacity (Ah) Formula: Watt-hours ÷ System Voltage (V)
Example: 240 Wh ÷ 12V = 20 Ah
Inverter Size (W) Formula: Total Watts × 1.25 (safety margin)
Example: 300W × 1.25 = 375W → Use 400W inverter
Total Load Power (W) Formula: Sum of all appliance watts used simultaneously
Example: Light (10W) + Fan (75W) = 85W
Runtime (hrs) of Battery Formula: (Battery Ah × Voltage) ÷ Total Load (W)
Example: (100Ah × 12V) ÷ 240W = 5 hrs

Find Your Power Match

Need / Application System Recommendation
Basic lighting + phone charging Recommended Battery: 50Ah – 100Ah (12V)
Inverter Size: 100W – 200W
Notes: For small backup setups
Home office (laptop, fan, TV) Recommended Battery: 150Ah – 200Ah (12V or 24V)
Inverter Size: 500W – 1000W
Notes: For moderate usage with 4–6 hours of backup
Home backup (fridge, lights) Recommended Battery: 200Ah+ (24V or 48V recommended)
Inverter Size: 1000W – 1500W
Notes: Ideal for longer backups or heavier loads
Business / shop power backup Recommended Battery: 300Ah+ (48V system)
Inverter Size: 2000W – 3000W
Notes: Suitable for commercial setups or extended power outages

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  • Expert Energy Guidance: Our solar and backup energy specialists are here to help with system design, product questions, and installation tips.
  • USA-Based Service: Local, knowledgeable, and friendly support right here in the U.S.
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  • Built for Energy Independence: Whether powering a cabin, prepping for emergencies, or going off-grid, our products are chosen for performance, reliability, and sustainability.

EG4 FlexBoss21 Hybrid Inverter

$4,199.00