Outback FLEXpower Four 12kW 48V Pre-wired FXR Series System 120/240
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Fortress Power Envy 12 kW Solar Storage Inverter
Overview:
The Fortress Power Envy True 12 kW serves as a comprehensive solar storage solution tailored for modern energy needs. Below are its prominent features and benefits:
Main Features:
- Comprehensive Solution: Integrates PV, Generator, On/Off Grid, and AC/DC Coupling functionalities.
- 200A Whole Home AC Passthrough and Backup capability.
- Supports up to 18 kW of PV power directed to both battery and AC outputs.
- Provides a robust 12 kW (50A @240V) for backup power.
- Swift installation facilitated by integrated AC & DC breakers.
- Equipped with an APsmart Rapid Shutdown Transmitter and Button for enhanced safety.
Key Attributes:
- Accommodates 200A AC passthrough for complete home backup.
- Supports 3 MPPT outputs catering to a maximum of 21 kW PV array.
- Versatile coupling options including AC, DC, and combined AC/DC.
- Designed for both indoor and outdoor installations with an IP65 rating.
- Features an integrated generator input.
- Scalable up to 10 units in parallel.
- Provides local and remote monitoring capabilities via a color LCD touch screen and dedicated app.
- Allows for batch settings to streamline operations.
Fortress Power eFlex 5.4 Lithium Battery Storage:
Crafted to be exceptionally robust, the eFlex 5.4 battery is engineered for diverse applications and challenging weather conditions. Key highlights include:
- Incorporation of Tier 1 Automotive Prismatic Lithium Iron Phosphate Cells ensuring peak cycle life.
- Innovative enclosure design ensuring superior thermal performance, surpassing competitors.
- Boasts an IP65 rating, making it resistant to dust and water, ideal for outdoor installations.
- Offers versatile mounting options including wall-mount, floor-stand, or standard 19” industrial server rack.
DuraRack for eFlex 5.4 kWh Lithium Batteries:
The DuraRack enhances energy storage capabilities by accommodating up to 4 eFlex 5.4kWh batteries. Here are its primary features:
- Designed with NEMA 3R standards ensuring water and dust resistance for both indoor and outdoor setups.
- Comes with integrated busbars and battery cables, facilitating hassle-free stacking.
- Provision for a DIN rail thermostat catering to colder climates.
- Incorporates passive cooling vents ensuring optimal performance in warmer environments.
- Modular design allows expansion up to 4 units, equivalent to 81 KWH capacity.
Fortress Power Guardian:
Elevate your battery monitoring experience with the Fortress Power Guardian. This gateway device seamlessly connects Fortress Power Batteries to the cloud, offering real-time monitoring and enhanced support functionalities. Features include:
- Wi-Fi connectivity ensuring automatic detection of connected Fortress Power Batteries.
- Comprehensive battery-level monitoring covering State of Charge, Voltage, Current, and Temperature.
- Facilitates hassle-free warranty submissions for added peace of mind.
- Enables remote firmware updates ensuring batteries remain up-to-date.
- Streamlines technical support by allowing direct communication with Fortress engineers through live chat via the companion app.
Description
Fortress Power Envy 12 kW Solar Storage Inverter
Overview:
The Fortress Power Envy True 12 kW serves as a comprehensive solar storage solution tailored for modern energy needs. Below are its prominent features and benefits:
Main Features:
- Comprehensive Solution: Integrates PV, Generator, On/Off Grid, and AC/DC Coupling functionalities.
- 200A Whole Home AC Passthrough and Backup capability.
- Supports up to 18 kW of PV power directed to both battery and AC outputs.
- Provides a robust 12 kW (50A @240V) for backup power.
- Swift installation facilitated by integrated AC & DC breakers.
- Equipped with an APsmart Rapid Shutdown Transmitter and Button for enhanced safety.
Key Attributes:
- Accommodates 200A AC passthrough for complete home backup.
- Supports 3 MPPT outputs catering to a maximum of 21 kW PV array.
- Versatile coupling options including AC, DC, and combined AC/DC.
- Designed for both indoor and outdoor installations with an IP65 rating.
- Features an integrated generator input.
- Scalable up to 10 units in parallel.
- Provides local and remote monitoring capabilities via a color LCD touch screen and dedicated app.
- Allows for batch settings to streamline operations.
Fortress Power eFlex 5.4 Lithium Battery Storage:
Crafted to be exceptionally robust, the eFlex 5.4 battery is engineered for diverse applications and challenging weather conditions. Key highlights include:
- Incorporation of Tier 1 Automotive Prismatic Lithium Iron Phosphate Cells ensuring peak cycle life.
- Innovative enclosure design ensuring superior thermal performance, surpassing competitors.
- Boasts an IP65 rating, making it resistant to dust and water, ideal for outdoor installations.
- Offers versatile mounting options including wall-mount, floor-stand, or standard 19” industrial server rack.
DuraRack for eFlex 5.4 kWh Lithium Batteries:
The DuraRack enhances energy storage capabilities by accommodating up to 4 eFlex 5.4kWh batteries. Here are its primary features:
- Designed with NEMA 3R standards ensuring water and dust resistance for both indoor and outdoor setups.
- Comes with integrated busbars and battery cables, facilitating hassle-free stacking.
- Provision for a DIN rail thermostat catering to colder climates.
- Incorporates passive cooling vents ensuring optimal performance in warmer environments.
- Modular design allows expansion up to 4 units, equivalent to 81 KWH capacity.
Fortress Power Guardian:
Elevate your battery monitoring experience with the Fortress Power Guardian. This gateway device seamlessly connects Fortress Power Batteries to the cloud, offering real-time monitoring and enhanced support functionalities. Features include:
- Wi-Fi connectivity ensuring automatic detection of connected Fortress Power Batteries.
- Comprehensive battery-level monitoring covering State of Charge, Voltage, Current, and Temperature.
- Facilitates hassle-free warranty submissions for added peace of mind.
- Enables remote firmware updates ensuring batteries remain up-to-date.
- Streamlines technical support by allowing direct communication with Fortress engineers through live chat via the companion app.
what’s included
The E2000LFP Expandable Power Station combines power and flexibility in a portable package. Link it with two EB3000 battery packs to reach an impressive 8064Wh capacity - enough for almost any power need.
With 2000W AC output, it runs most household devices and tools without breaking a sweat. The advanced LiFePo4 batteries deliver outstanding durability, keeping 80% capacity even after 3500 charging cycles.
Charging is quick and flexible. The station accepts up to 1300W input across multiple ports, with 600W maximum solar input. Using solar panels, you'll fully charge in 2-3 hours. Need it faster? Dual AC adapters cut that time to just 1.5-2 hours.
Specification
The E2000LFP Expandable Power Station combines power and flexibility in a portable package. Link it with two EB3000 battery packs to reach an impressive 8064Wh capacity - enough for almost any power need.
With 2000W AC output, it runs most household devices and tools without breaking a sweat. The advanced LiFePo4 batteries deliver outstanding durability, keeping 80% capacity even after 3500 charging cycles.
Charging is quick and flexible. The station accepts up to 1300W input across multiple ports, with 600W maximum solar input. Using solar panels, you'll fully charge in 2-3 hours. Need it faster? Dual AC adapters cut that time to just 1.5-2 hours.
Shipping & Delivery
The E2000LFP Expandable Power Station combines power and flexibility in a portable package. Link it with two EB3000 battery packs to reach an impressive 8064Wh capacity - enough for almost any power need.
With 2000W AC output, it runs most household devices and tools without breaking a sweat. The advanced LiFePo4 batteries deliver outstanding durability, keeping 80% capacity even after 3500 charging cycles.
Charging is quick and flexible. The station accepts up to 1300W input across multiple ports, with 600W maximum solar input. Using solar panels, you'll fully charge in 2-3 hours. Need it faster? Dual AC adapters cut that time to just 1.5-2 hours.
Get Started In 3 Simple Steps
The whole process is easy – no salespeople involved.

Step 1: Choose Your System
Pick your products at direct-to-you prices. Browse complete systems and see exactly what you'll pay.

Step 2: Place Your Order
Quick online checkout with free U.S. shipping. Your order ships within 3-5 business days.

Step 3: Power Up
Professional guidance for setup and connection. Our team helps you get the most from your power station.
The Build The Power Difference
Here’s why you’ll prefer us over other providers.
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What Our Customers Say
Direct experiences from homeowners who took control of their energy costs.
Frequently Asked Questions
How is Build The Power different from other companies?
Unlike traditional companies, we've removed the complex network of salespeople, project managers, and dealer fees. You browse and buy directly through our digital platform, cutting costs by 20-50% while still getting expert support when you need it.
How does your ordering process work?
Browse & Select – Find the product that suits your needs.Add to Cart – Click "Add to Cart" and proceed to checkout. Secure Payment – Complete your purchase using our secure payment options. Order Confirmation – You’ll receive an email confirmation with your order details. Shipping & Delivery – We process and ship your order as quickly as possible. A tracking number will be provided. If you have any questions, feel free to contact us!
Do you offer free shipping?
Yes! We offer free shipping on all orders, with no minimum purchase required. Enjoy hassle-free shopping without worrying about extra shipping costs. Once your order is processed, we’ll provide a tracking number so you can follow your shipment’s progress.
What's your return policy?
We offer a 30-day return policy for your peace of mind. If you're not completely satisfied with your purchase, you can return it within 30 days of delivery for a refund or exchange. The item must be in its original condition and packaging.
To start a return, contact our support team, and we’ll guide you through the process.
Can I get help with installation?
We do not offer installation services, but we’re happy to recommend trusted companies or services that can assist you. If you need help finding an installer, feel free to contact us, and we’ll point you in the right direction!