The Sol-Ark 12K-2P-LL is a hybrid inverter/charger built for whole-home backup and solar self-consumption. It runs on a 48V battery bank, outputs 120/240VAC split-phase power, and supports both grid-tied and off-grid operation for homeowners who want resilient power without oversized budgets.
This is a hybrid architecture unit: it operates grid-tied with NEM sell-back capability, provides battery backup during outages via a 5ms transfer time, and also supports fully off-grid operation. It is not a chargeverter and it is not an off-grid-only inverter — it is designed to move between grid-interactive and battery-backup modes automatically. It carries multiple UL 1741 certifications for utility interconnection and IEEE 1547.1-2020 compliance. 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: 120/240VAC split-phase, also configurable for 120/208VAC; nominal frequency 50/60Hz.
- Battery DC Voltage: 48V nominal, operating range 43-59V. NOT compatible with 12V or 24V battery banks.
- Continuous AC Output to Loads/Grid: 9,000W. Continuous DC Output to Batteries: 3,000W. Combined maximum continuous throughput: 12,000W.
- Peak Surge Power (10 seconds): 24,000W — this is a surge rating, not a continuous rating.
- Max Grid Passthrough Current: 100A.
- Backup transfer time: 5ms.
- Does NOT function as a standalone chargeverter (AC-to-DC charging only) — it is a bidirectional hybrid inverter/charger.
- UL 9540 applies only at the certified system level (inverter + specific battery combination) — it is not a blanket rating on the inverter alone.
Neutral-ground bonding is the most common failed-inspection point on split-phase hybrid inverters like the 12K-2P-LL. In grid-tied mode, the neutral must float and bond only at the main service panel; in off-grid or backup mode with the internal transfer relay engaged, you can create an unintended double-bond if the sub-panel also carries a bonded neutral. This causes ground-fault nuisance trips and, worse, can defeat the equipment ground path during a fault. Verify bonding points with a digital multimeter (checking for unwanted neutral-ground current) before energizing the system, and confirm your panel configuration matches NEC Article 690 and 706 requirements for the utility's interconnection agreement. Get this wrong and you'll fail utility inspection on the first visit — get it right and it's a one-time check that never needs revisiting.
Key Benefits
- 5ms transfer time between grid and battery backup — fast enough that most sensitive electronics won't reset.
- 3 MPPT inputs support both DC and AC solar coupling for new installs and retrofits.
- 100A grid passthrough plus 250A integrated battery breaker/disconnect for load flexibility.
- Integrated PV rapid shutdown, ground fault detection, and arc fault detection per NEC requirements — no separate combiner box needed for these functions.
- Multifunction GEN port supports auto generator start for extended outages.
- Supports lead-acid or lithium battery chemistries with BMS communication (RS485/CAN) for closed-loop lithium setups.
| Spec | Value | Unit |
|---|---|---|
| Continuous AC Output (Loads/Grid Sell) | 9,000 | W |
| Continuous DC Output (Battery) | 3,000 | W |
| Combined Max Continuous Output | 12,000 | W |
| Peak Surge Power (10s) | 24,000 | W |
| DC Battery Voltage (Nominal) | 48 | V |
| Battery Operating Voltage Range | 43 - 59 | V |
| AC Output Voltage | 120/240, 120/208 | VAC |
| Rated Frequency | 50 / 60 | Hz |
| Max STC Rated PV Power | 19,200 | W |
| MPPT Operating Voltage Range | 150 - 425 | V |
| Max PV Input Voltage | 500 | V |
| Number of MPPT Inputs | 3 | - |
| Backup Transfer Time | 5 | ms |
| Max Grid Passthrough Current | 100 | A |
| AC Output Breaker | 63 | A |
| Battery Breaker/Disconnect | 250 | A |
| Efficiency | 96 | % |
| THDv | < 2.5 | % |
| Idle/No-Load Consumption | 60 | W |
| Operating Temperature Range | -40 to 60 | °C |
| Weight | 653 | kg (per source unit listing) |
| Standard Warranty | 10 | Years |
Note: See "Resources (System Manuals and Warranty)" Tab above for full specifications.
Compatibility & Fitment
- Compatible battery chemistries: Lead-acid or Lithium (LiFePO4-type), with BMS communication via RS485/CAN for closed-loop operation.
- Supports 48V nominal battery banks only. NOT compatible with 12V or 24V battery systems.
- Supports both DC-coupled and AC-coupled solar arrays for new installs and retrofit projects.
- Parallel RJ45 ports allow multi-unit stacking for larger systems — confirm current stacking limits with manufacturer documentation before design.
- Includes GEN port for auto generator start support. NOT a substitute for a transfer switch on non-supported generator types — confirm generator compatibility separately.
- Wi-Fi/Bluetooth/Ethernet dongle hardware is included standard per manufacturer data.
- NOT a standalone battery charger (Chargeverter) — this is a bidirectional hybrid inverter/charger.
Compliance & Environment
| Category | Detail |
|---|---|
| UL/IEEE Listings | UL 1741 SB, UL 1741 SA11, UL 1741 CRD-PCS, IEEE 1547.1-2020, UL 1699B, UL 1998, FCC Part 15 Class B, CSIP, CA Rule 21, HECO Rule 14H (SRD 2.0), CSA C22.2 107.1-16 |
| NEC Code Compliance | PV DC Disconnect (NEC 240.15), Ground Fault Detection (NEC 690.5), PV Rapid Shutdown (NEC 690.12), PV Arc Fault Detection (NEC 690.11) — all integrated |
| Surge Protection | DC Type II / AC Type II, integrated |
| Operating Altitude | Up to 2000 m (6561 ft) before derating applies |
| Noise | < 30 dB @ 25°C (77°F) |
FAQ
Can this inverter sell power back to the grid?
Yes. The 12K-2P-LL supports NEM grid sell-back and is UL 1741 SB listed for utility interconnection, in addition to backup and off-grid operation.
What battery voltage is required?
This unit requires a 48V nominal battery bank, with an operating range of 43-59V DC. It is NOT compatible with 12V, 24V, or other DC bank voltages.
Can I parallel multiple units together?
The unit includes dedicated Parallel RJ45 communication ports for stacking multiple inverters. Confirm current firmware and stacking limits with Sol-Ark documentation before designing a multi-unit system.
Is this UL 1741 listed for utility interconnection?
Yes. It carries UL 1741 SB, UL 1741 SA11, and UL 1741 CRD-PCS listings, along with IEEE 1547.1-2020 compliance, which utilities use to approve grid-interactive installations.
Does this inverter work with lead-acid batteries?
Yes, it supports lead-acid or lithium battery chemistries with BMS communication for closed-loop lithium setups.
Warranty & Registration
Sol-Ark provides a 10-year standard warranty on the 12K-2P-LL. For full warranty terms, product registration steps, and firmware update information, refer to the "Resources (System Manuals and Warranty)" Tab above on this page. If you're unsure how closed-loop battery communication affects warranty coverage on your specific battery pairing, ask us before you order — we always reply back.
