Knowledge base / Brands / Fox ESS / H3 Smart hybrid inverter

Fox ESS · Solar inverter model

H3 Smart hybrid inverter

Fox ESS H3 Smart is a three-phase hybrid inverter range spanning 5 to 15 kW with three MPPTs and a high-voltage battery connection.

Specifications

SpecificationValue
Typehybrid inverter
Supply phasesthree
Rated AC power (kW)5, 6, 8, 10, 12 and 15 in the current UK range
Maximum DC input (kW)11, 13.2, 17.6, 18, 22.5 and 22.5 for the UK-advertised ratings
MPPT count3
Maximum input current (A)20 per MPPT
Maximum efficiency (%)97.3 to 97.9
Euro efficiency (%)97.2
Battery compatibleyes
Battery-voltage range (V)100 to 800
Battery inputs1
Maximum battery current (A)50
Warranty (years)5 from installation, capped at 65 months from manufacture; extensions conditional
IP ratingIP65
Coolingnatural at 5, 6, 8, 9.9 and 10 kW; fan at 12 and 15 kW
MonitoringFoxCloud 2.0
EPS outputthree-phase
EPS changeover (ms)<10

Fox ESS H3 Smart is a three-phase hybrid inverter range. Its current UK schedule excludes the 9.9 kW regional variant in the June 2026 global datasheet.

H3 Smart string inputs and battery matching

The three MPPTs can track different string groups, but each string must use the exact model’s voltage and current schedule.

Supported battery selection depends on more than the published voltage window. The current UK page names EP5, EP6, EP11, EP12, EQ2900, EQ4300, EQ4800, EQ5000 and CQ7. The complete inverter and battery codes, current firmware and system documentation must match.

H3 Smart and H3 Pro overlap at 15 kW but use separate model schedules. The shared power class does not make their input limits interchangeable.

H3 Smart EPS and warranty records

The EPS feature does not identify the protected circuits or complete backup design.

Inverter cover is separate from battery cover. Registration evidence and the policy applying to the complete H3 Smart code should stay with the commissioning records because extensions are conditional and product-dependent.

Brand

Fox ESS

Reference type

Solar inverter model

Last reviewed

23 Jul 2026

Current status

Current in the manufacturer's UK range.