The Solis S6-EO1P5K-48 is a 5kW single-phase off-grid energy storage inverter designed for properties without grid access, unreliable grid supply, or those requiring a fully autonomous power system independent of the national grid. Unlike the Solis hybrid (RHI-5G) range, the S6-EO1P is an island inverter: it creates its own 230V AC supply from solar and a 48V LFP or lead-acid battery bank. It accepts generator input and can charge the battery from the grid as a backup source, but does not export to or synchronise with the grid. Key capabilities: 5kW continuous / 10kVA surge for 10 seconds (handles motor start loads and large appliances), pure sine wave output, 100A solar charging from up to 500V DC PV input, 100A battery charge/discharge, generator auto start/stop, and 6-unit parallel capability for up to 30kW (or configurable three-phase). WiFi included. CAN/RS485/Bluetooth BMS communications. 14 kg, 335 × 450 × 160 mm. Battery equalisation for extended battery life. AFCI arc-fault protection.
5kW
Rated output
10kVA
Surge 10 s
1 MPPT
500V DC
96.6%
Peak efficiency
6 units
Parallel to 30kW
IP21
Indoor rated
⚠ Qualified installer required: This inverter operates with high-voltage DC from PV panels and high-current DC from batteries. Installation must be performed by a qualified electrician. Although this is an off-grid inverter, any grid or generator connection must comply with applicable electrical regulations.
ℹ Off-grid inverter — not a grid-tied or hybrid unit: The S6-EO1P5K-48 is an island (off-grid) inverter. It does not connect to or export to the national grid. It generates its own 230V AC output from solar and batteries. It can accept a grid or generator input for battery charging, but it does not synchronise with or export to the grid. If you need a grid-tied solar inverter with battery storage and grid export, see the Solis RHI-5G / S5-EH1P hybrid inverter range instead.
Off-Grid vs Hybrid — Choosing the Right Solis Inverter
On-grid homes maximising self-consumption and SEG export
If your property has a stable mains supply and you want to maximise solar self-consumption and receive SEG export payments, choose the Solis RHI-5G hybrid range instead. If you want a fully autonomous power system with no grid connection required, choose the S6-EO1P5K-48.
Key Features
200% Surge Capacity — 10kVA for 10 Seconds
The S6-EO1P5K-48 can output 200% of its rated power (10kVA) for up to 10 seconds. This surge capability handles the high inrush current drawn by motor-start loads: pumps, compressors, fridge/freezer compressors, power tools, and air conditioning units. Motors typically draw 3 – 6× their running current at start-up. Without surge capacity, the inverter would shut down or throttle when these loads are switched on. At 10kVA peak, the S6-EO1P can start a 2.5 – 3kW motor load from a 5kW running-load system without interruption.
10kVA surge / 200%10 secondsMotor-start capable
Single MPPT, 500V DC — 1 or 2 String Inputs, 100A Solar Charging
The integrated solar charge controller handles up to 500V DC input with a 90 – 480V MPPT operating range. One MPPT with two parallel string inputs (both strings must be the same orientation and length). Max input current: 26A; max short-circuit current: 32A. The solar charger can deliver up to 100A to the battery, corresponding to approximately 5kW of solar-to-battery charging. Recommended max PV array: 5.5kW.
The S6-EO1P5K-48 includes a dedicated generator input that accepts up to 5kW / 80A. The inverter can automatically start the generator when battery SoC drops below a threshold and stop it when the battery is charged. Multiple generator connection methods are supported. Battery AC charging from the generator runs at up to 80A, allowing a 10kWh battery bank to be charged from empty in approximately 2 – 3 hours. This is essential for off-grid systems in the UK winter when solar yield drops below system load for extended periods.
Auto generator start/stop5kW / 80A inputBattery AC charge 80A
6-Unit Parallel — Up to 30kW Single-Phase or Three-Phase Microgrid
Up to 6 S6-EO1P5K-48 units can be connected in parallel, building a 30kW single-phase system, or configured as a three-phase microgrid (2 units per phase in a balanced 10kW three-phase configuration, or other combinations up to the parallel limit). This makes the S6-EO1P a scalable platform for larger off-grid properties, smallholdings, commercial outbuildings, remote telecoms sites, and community microgrids. Parallel installation requires synchronisation cabling and careful commissioning.
Up to 6 in parallel30kW single-phaseThree-phase capable
6 TOU Charge/Discharge Schedules + Force-Charge Mode
Six programmable time-of-use (TOU) windows allow the battery to charge or discharge at specific times of day. This is valuable in systems that can also access grid power (when fitted with grid connection): schedule overnight charging at cheap tariff rates, then discharge during peak demand. One-click force-charge mode immediately starts charging the battery from whatever source is available — useful when a storm is forecast and maximum battery reserve is needed. A dedicated force-charging period can be set to capture low-rate electricity and optimise revenue from tariff differentials.
6 TOU schedulesForce-charge modePrice optimisation
Battery Equalisation + AFCI Arc-Fault Protection
Battery equalisation periodically applies a controlled overcharge to balance cell voltages within the battery bank. This is particularly important for lead-acid batteries, where cell imbalance is a primary cause of premature failure. LFP lithium batteries also benefit from occasional balancing. The equalisation function can extend battery life significantly in off-grid systems that undergo deep daily cycling. AFCI (Arc-Fault Circuit Interrupt) on the DC side detects resistive arcing in the PV cable before it can start a fire, and disconnects the faulty string automatically.
Battery equalisationAFCI arc detectionExtends battery life
A WiFi stick is included in the box. Once connected, the inverter is visible in SolisCloud for real-time monitoring of PV input, battery SoC, load power, and system status. OTA firmware updates can be pushed remotely. For battery BMS communication, the inverter supports CAN, BMS protocol, RS485, Bluetooth, and dry-contact, covering virtually every 48V lithium battery on the market. A dry-contact interface allows non-communicating batteries (lead-acid, basic lithium) to be integrated without a BMS protocol.
Up to 6 units (30 kW single-phase; 3-phase configurable)
Dimensions (W × H × D)
335 × 450 × 160 mm
Weight
14 kg
IP rating
IP21 (indoor installation required)
Operating temperature
−10°C to +60°C
Storage temperature
−25°C to +60°C
Relative humidity
5 – 95 % (non-condensing)
Max operating altitude
2,000 m
Communications
Interfaces
CAN, BMS, RS485, Dry-contact, Bluetooth
WiFi
WiFi stick included in box
Display
LCD
Safety and Certifications
Safety standard
IEC 62109, IEC 61000
AFCI
Yes — DC arc-fault circuit interrupt
Additional protections
Over-voltage, over-current, short-circuit, surge, temperature
Frequently Asked Questions
Does this inverter connect to the national grid?
No. The S6-EO1P5K-48 is an island (off-grid) inverter. It does not synchronise with or export to the national grid. It creates its own 230V AC supply from PV and battery. It can accept grid or generator power as a battery charging source, but it cannot grid-tie or act as a grid-export inverter. If you need a grid-connected hybrid inverter with SEG export capability, see the Solis RHI-5G / S5-EH1P hybrid range (3kW, 3.6kW, 5kW, 6kW).
What battery types are compatible?
Both lithium-ion (LFP) and lead-acid 48V batteries are supported. For lithium batteries with BMS communication, use CAN or RS485 to connect the BMS. For non-communicating batteries (sealed lead-acid, AGM, basic lithium without BMS), the dry-contact interface provides a simpler connection path. Bluetooth is also supported for compatible BMS systems. Check the Solis compatible battery list for verified brands and models.
Can I use this inverter for a three-phase system?
Yes, with multiple units. Two units per phase (with balancing and synchronisation cabling) can form a three-phase 10kW system, or other phase/power combinations are possible within the 6-unit parallel limit (30kW total). Three-phase parallel installation requires careful commissioning to ensure all units are phase-locked and load-balanced. Consult the Solis parallel installation guide before designing a three-phase system.
Is IP21 adequate for a UK garage or outbuilding installation?
IP21 means the enclosure is protected against falling water droplets (vertically) but is not splash-proof or waterproof in any direction. It is suitable for dry indoor installation only: a utility room, dry garage interior, plant room, or similar indoor space. Do not install in a damp shed, unheated outbuilding with condensation, or anywhere with direct water exposure. The operating temperature range (−10°C to +60°C) and the indoor installation requirement together define the suitable locations. If outdoor or damp-location installation is needed, a suitable IP65-rated external enclosure would be required.
How does the battery equalisation function work?
Battery equalisation applies a controlled overcharge voltage to the battery bank for a defined period. For lead-acid batteries, this balances individual cell voltages by driving the weaker cells to full charge — a process they cannot reach during normal cycling. Without periodic equalisation, cell imbalance in a lead-acid bank accumulates, reducing effective capacity and ultimately causing premature battery failure. For LFP lithium batteries, equalisation is less critical (the BMS handles cell balancing) but the inverter’s equalisation mode can still assist in maintaining balance in large multi-module banks. Configure the equalisation voltage, current limit and interval in the inverter settings according to the battery manufacturer’s specification.
What is the difference between the S6-EO1P5K-48 and the S5-EO1P5K-48?
The S6-EO1P5K-48 is the 6th-generation Solis off-grid inverter, with updated firmware, improved parallel capability (6 units vs 10 units on the S5-P), and enhanced TOU and generator management features. The S5-EO1P5K-48 is an earlier generation. Both use the same 48V low-voltage battery architecture and broadly similar specifications, but the S6 is the current production model with the latest SolisCloud monitoring platform integration.
Related Products
Solis 3kW Hybrid 5G Inverter
Grid-tied hybrid equivalent; G98; no generator input
Solis 5kW Hybrid 5G Inverter
Grid-tied hybrid; G99; for on-grid solar+storage
Dyness DL5.0C Pro 5.12kWh LFP Battery
Compatible 48V LFP battery; CAN/RS485 BMS
Pylontech US3000C 3.55kWh Battery
Compatible Pylontech LFP battery for off-grid systems
BTU & WATT Calculator
Room Dimensions
Room Type
Living Room
Bedroom
Kitchen
Bathroom
Conservatory
Hallway
Glazing Type
Single Glazed
Double Glazed
Triple Glazed
External Walls
0 Wall
1 Wall
2 Walls
3 Walls
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Insulation Level
Poor
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Required Heating
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0
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