
Fox ESS H3 Pro 25.0kW Hybrid Inverter with ECS4300 Battery stack of 7 (29.03kWh)
Fox ESS H3 Pro 25.0kW Hybrid Inverter with ECS4300 Battery stack of 7 (29.03kWh) is a complete Fox ESS energy storage package: a 25 kW AC hybrid inverter supplied with a 29.03 kWh battery stack of 7 modules, about 26.1 kWh usable at 90% depth of discharge.
The inverter rating is what the system can deliver at any instant — 25 kW to the house and, in a power cut, to the backup circuits. The battery capacity is how long it can keep doing it. Both matter, and they are different numbers.
| 6 x FE-HV-EQS-4300 | Fox EQ4300 4.32kWh HV Battery (Slave) | |
| 1 x FE-H3-PRO-25.0 | Fox ESS H3 Pro 25kW 3PH Hybrid Inverter | |
| 1 x FE-HV-ECM-4300 | Fox ECS 4.14kWh HV Battery (Master) | |
System specification
| Inverter | Fox H3 Pro 25kW 3ph Hybrid Inverter |
| Inverter rated AC power | 25,000 W |
| Inverter surge AC power | 27,500 W |
| Inverter maximum DC (PV) power | 37,500 W |
| Inverter MPPT trackers | 3 |
| Inverter efficiency | 97.4 % |
| Nominal battery capacity | 29.03 kWh |
| Usable battery capacity at 90% DoD | 26.1 kWh |
| Battery modules | 7 |
| Battery chemistry | LiFePO₄ prismatic cell |
| Depth of discharge | 90% |
| Round-trip efficiency | > 95% |
| Cycle life | ≥ 6,000 cycles at 25 °C, 90% DoD, 0.5C |
| Scalability | Up to 7 modules in series |
| Ingress protection | IP65 |
| Certification | IEC 62619, IEC 61000-6-1/2/3/4, UN38.3 |
Battery capacity is the manufacturer's nominal figure for this number of modules. Full electrical, mechanical and installation detail for each component is in its own datasheet and installation manual, all of which are in the Documents tab below.
Buying as a package
The components are ordered, delivered and priced as one line, but they are the same products sold individually — each is linked above, with its own specification and documentation. A hybrid inverter and battery installation is notifiable work: it needs a G98 or G99 application to the network operator before commissioning, and MCS certification if it is going on a grant or an export tariff.
Datasheets, installation manuals, warranty documents and declarations of conformity for every component in this package are in the Documents tab below. Contact our sales team at sales@clearraysolar.com for project pricing.
Build your complete solar system
Everything you need in one place.
- Inverters
- Batteries
- Mounting Systems
- Cabling & Accessories
- Protection Devices
Delivery times vary by region:
- UK — 1-2 business days
- Highlands & Islands — 1-2 business days
Returns accepted within 14 days of delivery for unused items in original packaging.


