The EG4 FlexBOSS18 is a 48V hybrid inverter/charger rated at 13,000 watts continuous output, built for off-grid and grid-tied battery backup applications with 120/240V split-phase power. It's designed for homeowners and installers who need whole-home backup with solar charging capability.
This is a hybrid inverter/charger architecture, meaning it can operate with battery storage and accept solar input while also interfacing with the grid or a generator, depending on your configuration. The provided manufacturer specifications do not include UL listing numbers, NEC code references, or NEMA enclosure ratings for this specific SKU — these are flagged below as [NEEDS VERIFICATION]. Note: If you would like to review the manufacturer Product Specifications, Warranty, Brochure, etc., for this system, please refer to the "Resources (System Manuals and Warranty)" Tab above on this page.
Critical Power & Interconnection Requirements
- AC Output: 120/240V split-phase
- Battery DC Input: 48V nominal
- Continuous AC Output: 13,000 W (13kW)
- Surge/Peak Output: [NEEDS VERIFICATION] — not specified in provided manufacturer data
- PV Input Capacity, MPPT range: [NEEDS VERIFICATION] — not specified in provided manufacturer data
- NOT compatible with 12V or 24V battery banks — 48V systems only
- NOT confirmed for grid sell-back / net metering — verify with manufacturer documentation before assuming export capability
- UL listing status: [NEEDS VERIFICATION] — not stated in provided source data
Neutral-ground bonding is the most common failed-inspection point on split-phase hybrid inverters like the FlexBOSS18. If the unit's internal bonding is left engaged in a subpanel installation, you'll create an unwanted parallel neutral-ground path that trips GFCI protection and confuses downstream monitoring. Verify bonding configuration with a digital multimeter (checking for continuity between neutral and ground bus outside the main service disconnect) before energizing the system. This single check prevents nuisance fault codes and failed utility or AHJ inspections. Document your bonding point per NEC Article 690/705 requirements for interconnected systems, and confirm local utility interconnection standards before commissioning — especially if any grid-tie functionality is enabled.
Key Benefits
- 13,000W continuous output supports whole-home backup loads on a single 48V unit
- 120/240V split-phase output works directly with standard North American home panels
- Hybrid architecture supports battery storage alongside solar charging input
- 48V battery platform aligns with common LiFePO4 server-rack and stackable battery formats
Technical Table
| Spec | Value | Unit |
|---|---|---|
| Continuous AC Output | 13000 | W |
| Battery DC Voltage | 48 | V |
| AC Output Voltage/Phase | 120/240 | V Split-Phase |
| Model | FlexBOSS18 | — |
Note: See "Resources (System Manuals and Warranty)" Tab above for full specifications.
Compatibility & Fitment
- Designed for 48V nominal battery banks.
- NOT compatible with 12V or 24V battery banks.
- Battery chemistry compatibility (LiFePO4, Lead-Acid, closed-loop comms brand list): [NEEDS VERIFICATION] — not specified in provided manufacturer data.
- Parallel/stacking capability and unit limits: [NEEDS VERIFICATION] — not specified in provided manufacturer data.
- Grid sell-back capability: [NEEDS VERIFICATION] — not confirmed in provided manufacturer data; do not assume net-metering export support.
Compliance & Environment Table
| Category | Detail |
|---|---|
| UL Listings | [NEEDS VERIFICATION] — not stated in provided source data |
| IEEE 1547 | [NEEDS VERIFICATION] — not stated in provided source data |
| NEC Article References | [NEEDS VERIFICATION] — not stated in provided source data |
| NEMA Enclosure Rating | [NEEDS VERIFICATION] — not stated in provided source data |
FAQ
Can this inverter sell power back to the grid?
[NEEDS VERIFICATION] The provided manufacturer data does not specify grid sell-back (net metering) capability for the FlexBOSS18. Confirm this with EG4 documentation before assuming grid export functionality.
What battery voltage is required?
The FlexBOSS18 operates on a 48V DC battery bank. It is not compatible with 12V or 24V battery banks.
Can I parallel multiple units together?
[NEEDS VERIFICATION] Parallel/stacking capability and unit limits are not specified in the provided manufacturer data. Contact us before ordering if you plan a multi-unit stack.
Is this UL 1741 listed for utility interconnection?
[NEEDS VERIFICATION] UL listing information is not included in the provided manufacturer data for this SKU. Check the Resources tab or ask us before ordering if utility interconnection approval is required.
Warranty & Registration
Manufacturer warranty terms for the FlexBOSS18 are not included in the provided source data. [NEEDS VERIFICATION] Please refer to the "Resources (System Manuals and Warranty)" Tab above on this page for exact warranty length, closed-loop vs. open-loop battery communication terms, and registration requirements. Ask us before you order if warranty terms affect your purchase decision — we always reply back.
