Fortress Power
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For systems where grid export is not required or not permitted, the Fortress Power Solo 6.5K is a 48V non-export hybrid inverter with 6,500W of continuous split-phase 120/240Vac output. It brings a 140A solar charge controller, dual MPPT inputs and grid or generator input together in one compact unit. Homeowners and installers building self-consumption or off-grid systems will find it a straightforward all-in-one option.
Planning a system? Read our guide: How to size a battery backup system for your home.
Residential backup, off-grid homes and self-consumption solar installations that store energy in batteries and use it on site.
About The Fortress Power Solo 6.5K is a 48V non-export hybrid inverter The Fortress Power Solo 6.5K is a 48V non-export hybrid inverter that delivers 6,500W of continuous split-phase 120/240Vac power. It is designed for residential backup power, off-grid systems, and self-consumption solar installations where grid export is not required or not permitted. This inverter combines a built-in 140A solar charge controller, dual MPPT inputs, and grid/generator input into a single compact unit, making it a straightforward option for homeowners and installers looking for an all-in-one solution without the complexity of stacking separate components. The “non-export” designation means this inverter does not feed power back to the utility grid. It is built for systems that store solar energy in batteries and use it locally. This makes it a good fit for areas where net metering is unavailable, where utilities restrict or prohibit grid export, or where the homeowner simply wants to maximize self-consumption of their solar production. It also simplifies permitting in many jurisdictions since non-export systems often face fewer interconnection requirements. Solar Input and Charge Controller The Solo 6.5K has two independent MPPT (Maximum Power Point Tracker) channels, each rated for up to 5,000W of PV input, for a combined total of 10kW of solar capacity. Each MPPT accepts a maximum open circuit voltage of 550Vdc with an operating voltage range of 150-450Vdc, providing flexibility for a variety of string configurations. The maximum input short circuit current is 18A per MPPT. The built-in charge controller supports up to 140A of DC charging current from solar, which means batteries charge quickly even during partial sun conditions. MPPT tracking efficiency is rated at 99.9%, so very little of the available solar energy is wasted in the conversion process. Grid and Generator Input The Solo 6.5K accepts both grid and generator AC input with intelligent automatic switching. When grid or generator power is available, the inverter can charge the battery bank at up to 9,600W from the grid or 4,000W from a generator. The input phase voltage range is 65-140Vac per leg, and the bypass overload current is rated at 40A. The switching time between power sources is 10ms typical, which is fast enough to keep most electronics and networking equipment running without interruption. For off-grid users with a backup generator, this means the inverter can automatically bring the generator online when battery SOC (State of Charge) drops to a user-defined level, charge the batteries, and then shut the generator back down. This extends the life of both the battery bank and the generator. Battery Compatibility The Solo 6.5K operates on a 48Vdc nominal battery bus with a voltage range of 40-60Vdc. It supports lithium batteries, lead-acid batteries, and user-defined battery types through its communication interfaces. The inverter communicates with battery management systems via RS485 and CAN bus, providing closed-loop monitoring of voltage, current, temperature, and SOC. The Solo 6.5K pairs naturally with Fortress Power’s own LFP battery lineup, including the eVault MAX, eFlex MAX, eForce, and eBoost systems. It is also compatible with third-party 48V battery banks. Scalable to 39kW A single Solo 6.5K provides 6,500W of continuous output, but the inverter supports parallel operation of up to six units for a combined output of 39kW. This makes the Solo 6.5K a scalable platform. A homeowner can start with one unit for essential loads and add more units as their energy needs grow or their budget allows. Three units can also be configured for three-phase 120Y/208V output. Time-of-Use Scheduling The inverter includes time-of-use (TOU) scheduling, which allows users to program charge and discharge cycles around their utility rate schedule. In areas with peak and off-peak electricity pricing, the inverter can charge batteries during low-rate periods and discharge them during
Warranty terms mentioned in this description are the manufacturer’s. Our own coverage is the 30-day limited warranty.
We confirm compatibility, installation requirements, and delivery details with you during order review, before any payment. Home electrical work may require a qualified installer.
Ask our team whether the Solo 6.5K fits your battery bank and local export rules. Message our team on WhatsApp.
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