Fox ESS H3 Pro 20 kW 3‑Phase Hybrid Inverter
- Three‑phase hybrid inverter combining PV generation and high‑voltage battery storage in one unit, ideal for commercial and light industrial sites on a 3‑phase supply.
- 20 kVA rated output with high DC input capability, giving headroom for larger arrays and flexible self‑consumption or peak‑shaving strategies.
- IP65‑rated, wall‑mounted design with remote monitoring via app and web portal, suitable for indoor plant rooms or sheltered outdoor installations in the UK.
Product overview
The Fox ESS H3 Pro 20 kW Three‑Phase Hybrid Inverter is part of the H3 Pro Series of three‑phase hybrid and AC inverters. It integrates PV, high‑voltage battery storage and grid interaction, allowing you to run commercial loads from solar, battery and grid with a single piece of hardware.
Paired with compatible Fox high‑voltage batteries, the H3‑Pro‑20.0 suits applications such as small warehouses, workshops, logistics depots and commercial offices that need dependable three‑phase power, self‑consumption optimisation and backup capability. Installation should be carried out by a qualified electrician or solar installer familiar with three‑phase hybrid systems.
Key Features
- Three‑phase hybrid operation with 20 kVA nominal AC power and support for high‑voltage batteries, providing a solid platform for larger commercial loads.
- High DC input power per MPP tracker, wide MPPT voltage range and dual MPPT / dual‑string architecture for flexible array design on complex roofs.
- Parallel operation of up to 10 storage inverters, enabling system expansion and higher site capacities over time.
- Smart fan‑cooled, IP65 wall‑mounted enclosure designed for outdoor use, with standby power modes to reduce idle consumption.
- Comprehensive protection suite including anti‑islanding, over‑current and over‑temperature protection, insulation monitoring and AC/DC surge protection.
Technical Specifications
The values below are taken from the Fox ESS H3 Pro Series datasheet (Version 1.6, 2023‑11‑22) for the H3‑Pro‑20.0 model. Always confirm against the latest official documentation before design or installation.
- Hybrid inverter model: H3‑Pro‑20.0.
- AC inverter model: AC3‑Pro‑20.0.
- Rated AC power (H3‑Pro‑20.0): 20000 VA.
- Max. apparent AC power (H3‑Pro‑20.0): 22000 VA.
- Max. AC power (series table): 30000 VA.
- Rated grid voltage (AC voltage range): 400 / 230 V; 380 / 220 V, 3L / N / PE.
- Rated grid frequency: 50 / 60 Hz, ±5.
- Max. AC current (per phase): 33.3 A.
- Power factor: 1 (adjustable from 0.8 leading to 0.8 lagging).
- Export control: Yes.
- THDI: <3 % @ rated power.
- Battery type: Lithium battery.
- Battery voltage range: 150 V – 800 V.
- Full AC load battery voltage: 220 V – 790 V.
- Max. charge/discharge current: 50 A + 50 A.
- Number of battery inputs: 2.
- Battery communication interface: CAN.
- Max. recommended DC power: 30000 W (series table for H3‑Pro‑20.0).
- Max. DC voltage: 1000 V (for 1000 V system, maximum operating voltage 950 V; PV input voltage >955 V reports PV overvoltage error).
- Nominal DC operating voltage: as per MPPT operating window (see MPPT voltage range).
- Max. input current: 32 A.
- Max. short‑circuit current: 40 A.
- MPPT voltage range: 230 V – 850 V.
- MPPT voltage range (full load): 220 V – 790 V.
- Start‑up voltage: 150 V (series value).
- Number of MPPT trackers: 2.
- Strings per MPPT tracker: 2.
- Max inverter backfeed current to the array: 0 A (as per series table).
- EPS max current (per phase): 30.3 A for 25000 VA EPS rating (series row covering H3‑Pro‑20.0).
- Max apparent AC power (EPS): 25000 VA.
- Peak apparent AC power (60 s, EPS): 30000 VA.
- THDV: <45 % (EPS output section).
- MPPT efficiency: 99.90 %.
- Max. efficiency: 97.80 %.
- Max. battery‑to‑AC efficiency: 97.60 %.
- Max. PV‑to‑battery efficiency: 98.10 %.
- Euro efficiency: 97.40 %.
- PV reverse polarity protection: Yes.
- Battery reverse protection: Yes.
- Anti‑islanding protection: Yes.
- Output short protection: Yes.
- Leakage current protection: Yes.
- Insulation resistor detection: Yes.
- Over‑voltage category: III (AC side), II (DC side).
- Reverse connect protection: Yes.
- Over‑current / over‑temperature protection: Yes.
- AC/DC surge protection: Type II / Type II.
- AFCI protection: Optional.
- DC switch: Optional.
- String monitoring function: Optional.
- Dimensions (W × H × D): 600 mm × 560 mm × 225 mm.
- Packing dimensions (W × H × D): 720 mm × 680 mm × 370 mm.
- Net weight: 52.5 kg.
- Gross weight: 57.5 kg.
- Installation: Wall‑mounted.
- Operating temperature range: −25 °C to +60 °C (derating at 45 °C).
- Storage temperature: −40 °C to +70 °C.
- Noise emission (typical): <60 dB (series values).
- Storage/operation relative humidity: 0–95 % (without condensation).
- Altitude: <4000 m.
- Protective class: I.
- Ingress protection: IP65 (for outdoor use).
- Standby consumption: 200 W for hot standby, 18 W for cold standby.
- Idle mode: Yes.
- Cooling: Smart FAN cooling.
- Inverter topology: Non‑isolated.
- Communication interfaces: Meter, Wi‑Fi, 4G (optional), DRM, USB, BMS (CAN), RS485.
- LCD display: Backlight 16 × 4 character.
- Buttons: Capacitive touch sensor × 4.
- Buzzer: 1, inside (EPS & Earth fault).
- Parallel operation: Yes, at max 10 PCS.
- Switch time: 0 ms (EPS output section).
- Safety standards: EN 62109‑1, EN 62109‑2.
- EMC standards: IEC 61000‑6‑2, IEC 61000‑6‑3.
Documents available for download
Please review the latest Fox ESS documentation before specifying, installing or commissioning the Fox ESS H3 Pro 20 kW Three‑Phase Hybrid Inverter.
Shipping and availability
We ship the Fox ESS H3 Pro 20 kW Three‑Phase Hybrid Inverter to the UK, Ireland, Africa, the Caribbean and worldwide. If a shipping rate is not shown at checkout, please contact us on +44 2080640335 or info@energian.co.uk for a tailored quote.
UK expert support
Energian provides UK‑based expert support for Fox ESS three‑phase hybrid systems. Get in touch via phone, email or live chat if you need help with sizing, compatibility checks or project design, or if you would like to visit our office for an in‑person consultation.
As this inverter forms part of a wider PV and battery system rather than a plug‑and‑play product, we strongly recommend installation and commissioning via our trusted professional partners or your chosen qualified installer. We can work directly with your contractor to ensure the Fox ESS H3 Pro 20 kW, batteries and protection equipment are configured safely and in line with Fox ESS guidance and local regulations.