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Price Match Guarantee 💲 Fast & Free Shipping 📦 No Sales Tax 💵 Post Purchase Support 🤝 Free Replacement Parts 🛠️ Dealer Warranty 👷🏼 Extended Warranty!

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EG4 FlexBOSS21 All-in-One Hybrid Inverter | 21kW PV Input | 48V Split Phase

EG4 FlexBOSS21 All-in-One Hybrid Inverter | 21kW PV Input | 48V Split Phase

SKU EG4FLEXBOSS21
Save $600.00
$4,799.00
$4,199.00

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EG4 FlexBOSS21 All-in-One Hybrid Solar Inverter

The EG4 FlexBOSS21 hybrid solar inverter is a flexible 48V split-phase inverter/charger that delivers the reliable power of the 18kPV with added adaptability. It is powerful enough to start a 5-ton AC unit and supports 21kW of PV input. With the ability to parallel up to 10 units, the FlexBOSS21 achieves an impressive total continuous output of 160kW using PV input. Equipped with three MPPTs, it provides optimal solar management, while the enhanced EG4 monitoring software offers complete remote control, including mobile alerts and remote settings adjustments. Its integration with GridBOSS ensures comprehensive management of the entire Energy Storage System (ESS).

The FlexBOSS21 blends efficiency, durability, and innovation, making it an excellent option for those in need of reliable energy solutions. With advanced monitoring and safety features, it delivers dependable power and assurance for both residential and commercial installations. Go off-grid, stay connected, or sell back to the grid. The choice is yours.

EG4 FlexBOSS21 All-in-One Hybrid Inverter Features

  • Flexible Power Options: Operate off-grid, with grid support, or sell excess power back to the grid.
  • High PV Input Voltage: Supports up to 600V DC, allowing reduced cable sizes.
  • Smart Connectivity: Remote access with Wi-Fi and closed-loop communication with compatible batteries.
  • Safety-First Design: Includes rapid shutdown, ground fault monitoring, arc-fault protection, and robust safety certifications.
 Placeholder Image

EG4 FlexBOSS21 All-in-One Hybrid Inverter Applications

  • Off-grid residential energy solutions
  • Grid-tied solar systems with battery backup
  • Commercial and industrial power management
  • Agricultural and farm energy systems
  • Backup power for emergency situations
  • Scalable energy systems for businesses and large properties
 Placeholder Image

What's Included

Everything you need is included with your product.
  • EG4 FlexBOSS21 All-in-One Hybrid Solar Inverter
  • 90A Breaker: Compatible only with the EG4 FlexBOSS21
  • Smart Port Breakers: Rated at 30A, 40A, 60A, and 80A.
  • User Manual

Please Note:
  • You must purchase a 70A Breaker separately for use with the EG4 18kPV Hybrid Inverter.
  • You must purchase a 50A Breaker separately for use with the EG4 12kPV Hybrid Inverter.
  • A 125A Breaker (sold separately) can be used with either the Smart Port or Gen Port.

EG4 FlexBOSS21 All-in-One Hybrid Inverter Specifications
Specification Details
Input Voltage Range 120/240VAC; 120/208VAC (Split-phase)
Output Power 16kW continuous when using pv input, with a peak surge capacity of 24kW
Dimensions 29.5 x 20.5 x 11.2 inches
Weight 88 lbs
Warranty 10-year standard warranty, covering all major components

Frequently-Asked Questions

Can the EG4 FlexBOSS21 operate both off-grid and grid-tied?

Yes! The FlexBOSS21 is designed for off-grid energy independence, grid-tied integration, and hybrid operation with battery backup.

What battery types are compatible with this inverter?

This inverter is optimized for 48V LiFePO4 battery banks, ensuring efficient and long-lasting performance.

Can I expand my system with additional inverters?

Yes, the FlexBOSS21 supports parallel operation, allowing multiple units to be stacked for increased energy output.

Does it support remote monitoring?

Yes! The Wi-Fi and RS485 connectivity allow real-time system monitoring and control via the EG4 app.

Manual and Specifications

Shipping is FREE on all orders to customers within the 48 Contiguous States and the District of Columbia. We do not ship to Alaska, Hawaii, or any outlying islands and territories.

Processing time for orders is 1 business day

Shipping time for orders is 4-5 business days


Want to know more about our Returns Policy? Read more here.

Want to know more about our Shipping Policy? Read more here.

We get it. You've got a lot of choice when it comes to online retailers. Here's why we think you should shop with us at Krato Power.

  • Family Owned & Operated. Ask for Alex (Owner) at any time!
  • 4-5 Day Free Shipping with free liftgate service to the 48 Contiguous States and the District of Columbia. No extra charges. Ever
  • NO Sales Tax except for IN
  • Secured Purchase. All Customer data is secured with SSL Encryption
  • 30 Day Easy Returns. Not happy with your product, we'll take it back no questions asked.
  • Exceptional Customer Service. Check out our About Us page.
  • Call or Text Us - We are really here! (In the USA). 1-888-855-7286
Based on 12 reviews
75%
(9)
17%
(2)
8%
(1)
0%
(0)
0%
(0)
11
T
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Tamara Spence (Chicago, IL)
Fits my needs

Installed this to use with a generator that was not compatible with my victron multiplus. This allowed me to keep my generator and use it for a backup supply to charge my EG4 batteries. I did not like the fact that when you adjust the current limit the charger resets to 0 and then ramps up instead of just going to the new setpoint from where it currently is.

Thank you for a great product.

B
EG4 48V Chargeverter GC INV029
Ben saxon (Ashburn, VA)
Need more in depth instructions

Moe in depth instructions would be great, i had an issue with input voltage too high, charger sensed it and would not charge batteries. Also had no fault lights or anything. There are lights you can see on the diodes on the side of the charger that will tell you it's not happy. I Figured it out the hard way. Other than some early growing pains it works great

S
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Jim B (Chicago, IL)
Excited so I pre-ordered

Although these are not in stock yet, this will be the best fit for my home. I have a 2200 sq foot house and was worried I would not have enough to power the A/C during a power outage along with the well pump and sump pump. I called in to make sure I had the right fit and Alex was so helpful and kind. He went out of his way to make sure everything was the right fit. This generator will hookup to my homes natural gas line, which is also what I wanted.

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Description

EG4 FlexBOSS21 All-in-One Hybrid Solar Inverter

The EG4 FlexBOSS21 hybrid solar inverter is a flexible 48V split-phase inverter/charger that delivers the reliable power of the 18kPV with added adaptability. It is powerful enough to start a 5-ton AC unit and supports 21kW of PV input. With the ability to parallel up to 10 units, the FlexBOSS21 achieves an impressive total continuous output of 160kW using PV input. Equipped with three MPPTs, it provides optimal solar management, while the enhanced EG4 monitoring software offers complete remote control, including mobile alerts and remote settings adjustments. Its integration with GridBOSS ensures comprehensive management of the entire Energy Storage System (ESS).

The FlexBOSS21 blends efficiency, durability, and innovation, making it an excellent option for those in need of reliable energy solutions. With advanced monitoring and safety features, it delivers dependable power and assurance for both residential and commercial installations. Go off-grid, stay connected, or sell back to the grid. The choice is yours.

EG4 FlexBOSS21 All-in-One Hybrid Inverter Features

  • Flexible Power Options: Operate off-grid, with grid support, or sell excess power back to the grid.
  • High PV Input Voltage: Supports up to 600V DC, allowing reduced cable sizes.
  • Smart Connectivity: Remote access with Wi-Fi and closed-loop communication with compatible batteries.
  • Safety-First Design: Includes rapid shutdown, ground fault monitoring, arc-fault protection, and robust safety certifications.
 Placeholder Image

EG4 FlexBOSS21 All-in-One Hybrid Inverter Applications

  • Off-grid residential energy solutions
  • Grid-tied solar systems with battery backup
  • Commercial and industrial power management
  • Agricultural and farm energy systems
  • Backup power for emergency situations
  • Scalable energy systems for businesses and large properties
 Placeholder Image

What's Included

Everything you need is included with your product.
  • EG4 FlexBOSS21 All-in-One Hybrid Solar Inverter
  • 90A Breaker: Compatible only with the EG4 FlexBOSS21
  • Smart Port Breakers: Rated at 30A, 40A, 60A, and 80A.
  • User Manual

Please Note:
  • You must purchase a 70A Breaker separately for use with the EG4 18kPV Hybrid Inverter.
  • You must purchase a 50A Breaker separately for use with the EG4 12kPV Hybrid Inverter.
  • A 125A Breaker (sold separately) can be used with either the Smart Port or Gen Port.

EG4 FlexBOSS21 All-in-One Hybrid Inverter Specifications
Specification Details
Input Voltage Range 120/240VAC; 120/208VAC (Split-phase)
Output Power 16kW continuous when using pv input, with a peak surge capacity of 24kW
Dimensions 29.5 x 20.5 x 11.2 inches
Weight 88 lbs
Warranty 10-year standard warranty, covering all major components

Frequently-Asked Questions

Can the EG4 FlexBOSS21 operate both off-grid and grid-tied?

Yes! The FlexBOSS21 is designed for off-grid energy independence, grid-tied integration, and hybrid operation with battery backup.

What battery types are compatible with this inverter?

This inverter is optimized for 48V LiFePO4 battery banks, ensuring efficient and long-lasting performance.

Can I expand my system with additional inverters?

Yes, the FlexBOSS21 supports parallel operation, allowing multiple units to be stacked for increased energy output.

Does it support remote monitoring?

Yes! The Wi-Fi and RS485 connectivity allow real-time system monitoring and control via the EG4 app.

Manual and Specifications

Shipping is FREE on all orders to customers within the 48 Contiguous States and the District of Columbia. We do not ship to Alaska, Hawaii, or any outlying islands and territories.

Processing time for orders is 1 business day

Shipping time for orders is 4-5 business days


Want to know more about our Returns Policy? Read more here.

Want to know more about our Shipping Policy? Read more here.

We get it. You've got a lot of choice when it comes to online retailers. Here's why we think you should shop with us at Krato Power.

  • Family Owned & Operated. Ask for Alex (Owner) at any time!
  • 4-5 Day Free Shipping with free liftgate service to the 48 Contiguous States and the District of Columbia. No extra charges. Ever
  • NO Sales Tax except for IN
  • Secured Purchase. All Customer data is secured with SSL Encryption
  • 30 Day Easy Returns. Not happy with your product, we'll take it back no questions asked.
  • Exceptional Customer Service. Check out our About Us page.
  • Call or Text Us - We are really here! (In the USA). 1-888-855-7286