FOX ESS KH10 - single-phase hybrid inverter 10 kW.

FOX ESS KH10 is a single-phase hybrid inverter rated at 10 kW with four independent MPPT inputs, a high-voltage LiFePO₄ battery at 85–480 V and generator support. Charge and discharge current 50 A, efficiency 97.8%, output current 43.5 A, MPPT efficiency 99.9%. Mass 29 kg, IP65, 5-year warranty.

Four MPPTs: almost unheard of on a single phase

Four independent tracking channels is a specification associated with commercial-class three-phase units. In a single-phase hybrid it occurs rarely, and it is precisely this feature that makes the KH10 interesting for demanding sites.

Ten kilowatts of panels means twenty-four to twenty-six modules. Laying that number out on a single slope succeeds only on an industrial shed. On a private house with a hipped roof, dormer windows and a chimney, the array inevitably splits into fragments.

Four MPPTs let each fragment operate at its own optimal point. A group on the north-east slope does not drag down the southern one, and a section shaded in the morning does not constrain the rest. On a complex roof this yields 8–15 per cent more annual generation than a two-tracker arrangement.

The stated tracking efficiency is 99.9%. That means the algorithm loses virtually no power searching for the operating point, even under rapidly changing cloud.

Ten kilowatts on a single phase: an honest discussion

Forty-three and a half amperes of nominal current is a reality to reckon with before purchase. A standard domestic supply of 25 or even 32 amperes will not pass that power.

So the KH10 makes sense in two scenarios. First: you already hold an elevated allocated capacity on a single-phase arrangement — which happens in older developments and in villages where a three-phase line simply does not exist. Second: the inverter works mainly for self-consumption and island mode, with export limited by configuration.

In the second case the battery and loads are fed directly from the panels, and the supply remains only a backup channel. Ten kilowatts of generation then create no difficulties at the meter at all.

Technical specifications

• rated power 10 kW, single phase;

• four independent MPPT inputs, tracking efficiency 99.9%;

• MPP range 80–500 V, maximum input voltage 600 V;

• high-voltage LiFePO₄ battery, 85–480 V;

• charge and discharge current 50 A;

• efficiency 97.8% peak, 97.4% European weighted;

• output current 43.5 A nominal, 45.7 A maximum;

• generator support, THD below 3%;

• IP65, passive cooling, noise below 30 dB;

• dimensions 450 × 527 × 208 mm, mass 29 kg.

Passive cooling at ten kilowatts

Natural convection instead of fans in a unit of this output is not a simple engineering task. It is solved with an extensive aluminium heatsink that effectively forms the entire enclosure.

The benefit is obvious: no fans means no bearings to wear, no dust packing into an impeller, no noise. A sound level below 30 decibels means the inverter can be placed next to living spaces.

The price is placement requirements. The unit needs free space below and above for draught, and it must not hang in direct midday sun on a south wall without a canopy. IP65 permits outdoor mounting, but shade is still needed.

Integration and control

Standard control is through FoxCloud from a phone: generation per each of the four trackers, battery state, consumption, and charge schedule settings.

For those building their own automation, Modbus TCP and RTU are available, along with ready integration with Home Assistant. This allows the inverter to be linked with a heat pump, a water heater or an EV charger and to run them precisely when solar surplus exists.

Night monitoring keeps the connection alive after sunset, so data on battery discharge during dark hours does not disappear from the charts.

Four MPPTs and ten kilowatts on one phase is a solution for a complex roof and an elevated allocated capacity. Send us the panel layout and your supply rating: we will check whether the KH10 will realise its potential at your site, and say honestly if another model suits better.