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Gray electronic device labeled 'FLEXBOSS 21' with 'EGU' logo
Electrical panel with open cover displaying internal components
Gray electronic device labeled 'FLEXBOSS 21' with 'EGU' logo
Description

EG4 FLEXBOSS21 HYBRID INVERTER

21kW PV Input Capacity | 48V Split-Phase Hybrid Inverter | Advanced ESS & Backup Power Solution

Overview

The EG4 FlexBOSS21 is a high-performance 48V split-phase hybrid inverter and charger designed for advanced residential and commercial energy systems. Built for demanding applications, it combines solar generation, battery storage, and grid interaction into a powerful and scalable energy platform.

With support for up to 21kW of PV input and the ability to start high inrush loads such as 5-ton air conditioning systems, the FlexBOSS21 is engineered for serious backup power and energy independence applications.

The system supports parallel operation with up to 16 units for large-scale ESS deployments while offering flexible solar design through three independent MPPTs. Combined with advanced remote monitoring and GridBOSS integration, the FlexBOSS21 provides complete control over modern solar-plus-storage systems.

Key Features

Key Features

Advanced hybrid inverter engineered for scalable backup power, solar optimization, and energy independence.
  • • 21kW Solar PV Input Capacity
  • • 48V Split-Phase Hybrid Inverter & Charger
  • • Supports Off-Grid, Grid-Assisted, and Grid-Export Operation
  • • High PV Voltage Support up to 600V DC
  • • Starts High Inrush Loads Including 5-Ton AC Units
  • • Parallel Support for Up to 16 Inverters
  • • Up to 256kW Combined Continuous Output with PV Input
  • • Three Independent MPPTs for Flexible Solar Design
  • • Remote Monitoring with Mobile Alerts & Configuration
  • • Seamless Integration with GridBOSS Energy Management
Applications

Applications

  • • Residential solar-plus-storage systems
  • • Whole-home backup power systems
  • • Light commercial and mixed-use installations
  • • Grid-tied systems with battery backup
  • • Off-grid and hybrid energy systems
  • • Scalable ESS deployments
Specifications

Specifications

  • General Model: EG4 FlexBOSS21
    Type: Hybrid Inverter / Charger
    Battery Voltage: 48V
  • PV & Output Max PV Input: 21kW
    PV Input Voltage: Up to 600V DC
    Output Voltage: 120/240V Split-Phase
    Parallel Support: Up to 16 Units
  • Monitoring & Protection Remote Monitoring: Wi-Fi Enabled
    MPPTs: 3 Independent MPPT Inputs
    Protection: Arc Fault, Ground Fault, Rapid Shutdown
    Compliance: UL 1741 & CEC Listed
  • Included EG4 FlexBOSS21 Hybrid Inverter (V1.1)
    Integrated Monitoring & Communication Hardware
    LCD Screen Kit Sold Separately

EG4 FlexBOSS21 | 48V Split-Phase Hybrid Inverter | 21kW PV Input | Parallel Scalable ESS | Advanced Solar + Battery Energy Management

FAQs

Frequently Asked Questions

1. What is the EG4 FlexBOSS21?
The FlexBOSS21 is a high-capacity 48V split-phase hybrid inverter and charger designed for residential, commercial, off-grid, and hybrid energy systems.
2. How much solar input does it support?
It supports up to 21kW of solar PV input capacity.
3. Can it run large appliances like HVAC systems?
Yes. It is capable of starting high inrush loads including 5-ton air conditioning systems.
4. Is this suitable for off-grid systems?
Yes. It supports off-grid, hybrid, and grid-assisted applications.
5. Can multiple units be connected together?
Yes. Up to 16 units can be paralleled for larger scalable ESS installations.
6. What battery voltage does it use?
It is designed for 48V battery systems.
7. Does it support battery communication?
Yes. It supports closed-loop communication with compatible battery systems.
8. How many MPPTs does it have?
It includes three independent MPPTs for flexible solar array configurations.
9. Can I monitor the system remotely?
Yes. The system supports remote monitoring, alerts, and remote configuration through EG4 monitoring platforms.
10. Is this compatible with GridBOSS?
Yes. It integrates seamlessly with GridBOSS for advanced ESS control and energy management.
11. Can it export power back to the grid?
Yes. It supports grid-export operation depending on utility approval and installation setup.
12. Is professional installation recommended?
Yes. Professional installation is strongly recommended for safety, proper commissioning, and code compliance.
13. Is the inverter outdoor rated?
Yes. It is designed for indoor and outdoor installation depending on local code and environmental conditions.
14. Does it include safety protections?
Yes. It includes rapid shutdown capability, ground fault monitoring, and arc-fault protection.
15. Who is this best for?
Ideal for homeowners, off-grid users, backup power systems, and scalable energy storage projects requiring high PV capacity and advanced system flexibility.

Your payment details are safe and secure. We accept the following:

American Express
Diners Club
Discover
Google Pay
JCB
Mastercard
Visa

EG4 FlexBOSS21 Hybrid Inverter – 48V Split-Phase | 21kW PV Input

by RC City
SKU: 7559300415582
$4,099.00
Delivery 2- 5 Days
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Description

EG4 FLEXBOSS21 HYBRID INVERTER

21kW PV Input Capacity | 48V Split-Phase Hybrid Inverter | Advanced ESS & Backup Power Solution

Overview

The EG4 FlexBOSS21 is a high-performance 48V split-phase hybrid inverter and charger designed for advanced residential and commercial energy systems. Built for demanding applications, it combines solar generation, battery storage, and grid interaction into a powerful and scalable energy platform.

With support for up to 21kW of PV input and the ability to start high inrush loads such as 5-ton air conditioning systems, the FlexBOSS21 is engineered for serious backup power and energy independence applications.

The system supports parallel operation with up to 16 units for large-scale ESS deployments while offering flexible solar design through three independent MPPTs. Combined with advanced remote monitoring and GridBOSS integration, the FlexBOSS21 provides complete control over modern solar-plus-storage systems.

Key Features

Key Features

Advanced hybrid inverter engineered for scalable backup power, solar optimization, and energy independence.
  • • 21kW Solar PV Input Capacity
  • • 48V Split-Phase Hybrid Inverter & Charger
  • • Supports Off-Grid, Grid-Assisted, and Grid-Export Operation
  • • High PV Voltage Support up to 600V DC
  • • Starts High Inrush Loads Including 5-Ton AC Units
  • • Parallel Support for Up to 16 Inverters
  • • Up to 256kW Combined Continuous Output with PV Input
  • • Three Independent MPPTs for Flexible Solar Design
  • • Remote Monitoring with Mobile Alerts & Configuration
  • • Seamless Integration with GridBOSS Energy Management
Applications

Applications

  • • Residential solar-plus-storage systems
  • • Whole-home backup power systems
  • • Light commercial and mixed-use installations
  • • Grid-tied systems with battery backup
  • • Off-grid and hybrid energy systems
  • • Scalable ESS deployments
Specifications

Specifications

  • General Model: EG4 FlexBOSS21
    Type: Hybrid Inverter / Charger
    Battery Voltage: 48V
  • PV & Output Max PV Input: 21kW
    PV Input Voltage: Up to 600V DC
    Output Voltage: 120/240V Split-Phase
    Parallel Support: Up to 16 Units
  • Monitoring & Protection Remote Monitoring: Wi-Fi Enabled
    MPPTs: 3 Independent MPPT Inputs
    Protection: Arc Fault, Ground Fault, Rapid Shutdown
    Compliance: UL 1741 & CEC Listed
  • Included EG4 FlexBOSS21 Hybrid Inverter (V1.1)
    Integrated Monitoring & Communication Hardware
    LCD Screen Kit Sold Separately

EG4 FlexBOSS21 | 48V Split-Phase Hybrid Inverter | 21kW PV Input | Parallel Scalable ESS | Advanced Solar + Battery Energy Management

FAQs

Frequently Asked Questions

1. What is the EG4 FlexBOSS21?
The FlexBOSS21 is a high-capacity 48V split-phase hybrid inverter and charger designed for residential, commercial, off-grid, and hybrid energy systems.
2. How much solar input does it support?
It supports up to 21kW of solar PV input capacity.
3. Can it run large appliances like HVAC systems?
Yes. It is capable of starting high inrush loads including 5-ton air conditioning systems.
4. Is this suitable for off-grid systems?
Yes. It supports off-grid, hybrid, and grid-assisted applications.
5. Can multiple units be connected together?
Yes. Up to 16 units can be paralleled for larger scalable ESS installations.
6. What battery voltage does it use?
It is designed for 48V battery systems.
7. Does it support battery communication?
Yes. It supports closed-loop communication with compatible battery systems.
8. How many MPPTs does it have?
It includes three independent MPPTs for flexible solar array configurations.
9. Can I monitor the system remotely?
Yes. The system supports remote monitoring, alerts, and remote configuration through EG4 monitoring platforms.
10. Is this compatible with GridBOSS?
Yes. It integrates seamlessly with GridBOSS for advanced ESS control and energy management.
11. Can it export power back to the grid?
Yes. It supports grid-export operation depending on utility approval and installation setup.
12. Is professional installation recommended?
Yes. Professional installation is strongly recommended for safety, proper commissioning, and code compliance.
13. Is the inverter outdoor rated?
Yes. It is designed for indoor and outdoor installation depending on local code and environmental conditions.
14. Does it include safety protections?
Yes. It includes rapid shutdown capability, ground fault monitoring, and arc-fault protection.
15. Who is this best for?
Ideal for homeowners, off-grid users, backup power systems, and scalable energy storage projects requiring high PV capacity and advanced system flexibility.

Your payment details are safe and secure. We accept the following:

American Express
Diners Club
Discover
Google Pay
JCB
Mastercard
Visa

Frequently asked questions

Find answers to common questions about our products and services

Small orders ship via UPS or USPS (2-3 business days). Panels, batteries, and large items ship via LTL freight (3-5 business days)

We accept returns in accordance with our Return & Refund Policy. Please review the full details here:

Return & Refund Policy
Cancellation Policy

Yes, we ship to most countries worldwide. International shipping times vary by destination, typically 7-14 business days.

You will receive a tracking number via email once your order ships. Track it via the carrier’s website.

We accept all major credit/debit cards, PayPal, ACH/wire transfers and secure checkout options.

Yes. Net 30 is available for approved customers on second and subsequent orders only. Not available on first orders.

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Description

EG4 FLEXBOSS21 HYBRID INVERTER

21kW PV Input Capacity | 48V Split-Phase Hybrid Inverter | Advanced ESS & Backup Power Solution

Overview

The EG4 FlexBOSS21 is a high-performance 48V split-phase hybrid inverter and charger designed for advanced residential and commercial energy systems. Built for demanding applications, it combines solar generation, battery storage, and grid interaction into a powerful and scalable energy platform.

With support for up to 21kW of PV input and the ability to start high inrush loads such as 5-ton air conditioning systems, the FlexBOSS21 is engineered for serious backup power and energy independence applications.

The system supports parallel operation with up to 16 units for large-scale ESS deployments while offering flexible solar design through three independent MPPTs. Combined with advanced remote monitoring and GridBOSS integration, the FlexBOSS21 provides complete control over modern solar-plus-storage systems.

Key Features

Key Features

Advanced hybrid inverter engineered for scalable backup power, solar optimization, and energy independence.
  • • 21kW Solar PV Input Capacity
  • • 48V Split-Phase Hybrid Inverter & Charger
  • • Supports Off-Grid, Grid-Assisted, and Grid-Export Operation
  • • High PV Voltage Support up to 600V DC
  • • Starts High Inrush Loads Including 5-Ton AC Units
  • • Parallel Support for Up to 16 Inverters
  • • Up to 256kW Combined Continuous Output with PV Input
  • • Three Independent MPPTs for Flexible Solar Design
  • • Remote Monitoring with Mobile Alerts & Configuration
  • • Seamless Integration with GridBOSS Energy Management
Applications

Applications

  • • Residential solar-plus-storage systems
  • • Whole-home backup power systems
  • • Light commercial and mixed-use installations
  • • Grid-tied systems with battery backup
  • • Off-grid and hybrid energy systems
  • • Scalable ESS deployments
Specifications

Specifications

  • General Model: EG4 FlexBOSS21
    Type: Hybrid Inverter / Charger
    Battery Voltage: 48V
  • PV & Output Max PV Input: 21kW
    PV Input Voltage: Up to 600V DC
    Output Voltage: 120/240V Split-Phase
    Parallel Support: Up to 16 Units
  • Monitoring & Protection Remote Monitoring: Wi-Fi Enabled
    MPPTs: 3 Independent MPPT Inputs
    Protection: Arc Fault, Ground Fault, Rapid Shutdown
    Compliance: UL 1741 & CEC Listed
  • Included EG4 FlexBOSS21 Hybrid Inverter (V1.1)
    Integrated Monitoring & Communication Hardware
    LCD Screen Kit Sold Separately

EG4 FlexBOSS21 | 48V Split-Phase Hybrid Inverter | 21kW PV Input | Parallel Scalable ESS | Advanced Solar + Battery Energy Management

FAQs

Frequently Asked Questions

1. What is the EG4 FlexBOSS21?
The FlexBOSS21 is a high-capacity 48V split-phase hybrid inverter and charger designed for residential, commercial, off-grid, and hybrid energy systems.
2. How much solar input does it support?
It supports up to 21kW of solar PV input capacity.
3. Can it run large appliances like HVAC systems?
Yes. It is capable of starting high inrush loads including 5-ton air conditioning systems.
4. Is this suitable for off-grid systems?
Yes. It supports off-grid, hybrid, and grid-assisted applications.
5. Can multiple units be connected together?
Yes. Up to 16 units can be paralleled for larger scalable ESS installations.
6. What battery voltage does it use?
It is designed for 48V battery systems.
7. Does it support battery communication?
Yes. It supports closed-loop communication with compatible battery systems.
8. How many MPPTs does it have?
It includes three independent MPPTs for flexible solar array configurations.
9. Can I monitor the system remotely?
Yes. The system supports remote monitoring, alerts, and remote configuration through EG4 monitoring platforms.
10. Is this compatible with GridBOSS?
Yes. It integrates seamlessly with GridBOSS for advanced ESS control and energy management.
11. Can it export power back to the grid?
Yes. It supports grid-export operation depending on utility approval and installation setup.
12. Is professional installation recommended?
Yes. Professional installation is strongly recommended for safety, proper commissioning, and code compliance.
13. Is the inverter outdoor rated?
Yes. It is designed for indoor and outdoor installation depending on local code and environmental conditions.
14. Does it include safety protections?
Yes. It includes rapid shutdown capability, ground fault monitoring, and arc-fault protection.
15. Who is this best for?
Ideal for homeowners, off-grid users, backup power systems, and scalable energy storage projects requiring high PV capacity and advanced system flexibility.