Sunsynk 3.6kW AC 7kWp ECCO Hybrid Inverter

Sunsynk 3.6kW ECCO Hybrid Solar Inverter, 7kWp Dual MPPT

The Sunsynk 3.6kW ECCO is a single-phase hybrid for 48 V batteries, and the reason it gets specified so often on smaller roofs is the gap between its two numbers: it takes 7 kWp of panels but exports 3.6 kW. The surplus does not go to waste – the inverter charges the battery and feeds the house at the same time, so a bigger array still earns its keep on a limited grid connection.

At 15.7 A rated output it sits just inside G98's 16 A per phase, which is what makes it the usual answer for a house where a larger inverter would mean a G99 application. Two MPP trackers, a built-in DC switch, and the datalogger and CT clamp already in the box.

ECCO 3.6kW at a glance

What's in the box

Taken from the parts list in Sunsynk's ECCO SG04LP1 user manual (v15), section 4.1. Two of these items are usually a separate purchase on other brands – the datalogger and the CT clamp are both supplied here.

Panels and strings

Two MPP trackers, one string each at up to 13 A. They work between 150 V and 425 V, the inverter wakes at 125 V, and 500 V is the hard input limit – so size each string's open-circuit voltage on the coldest morning of the year and keep it under 500 V.

The headline is the 7 kWp ceiling against a 3.6 kW output: just under double. On a UK roof that array rarely produces its full nameplate figure, so the clipping people worry about mostly happens for a few hours around midday in high summer. The rest of the year the extra panels are what fills the battery.

Batteries and backup

Any 40–60 V battery suits it, lithium or lead-acid. High-voltage batteries are not compatible – the Sunsynk HV range needs an HV inverter, so match low voltage to low voltage.

Off-grid it delivers twice its rating for 10 seconds, which covers the start-up surge of a fridge compressor or a pump. With the grid present up to 35 A passes straight through, so those loads can draw more than 3.6 kW while the mains is on; in a power cut they have to fit inside it. It switches between grid-tied and off-grid automatically, export is fully programmable, and up to 16 units on matching firmware can be paralleled.

Grid approval

Warranty

Five years as standard from Sunsynk. The warranty has to be registered with Sunsynk after installation – it is not automatic from the purchase, so register the serial number once the unit is commissioned and keep the confirmation with the handover pack.

Order alongside

• Sunsynk 5.32kWh W5.3 Battery

  The usual first battery for this inverter. IP65, 48 V, and the cable sets are included with it.

• Sunsynk 10.64kWh W10.6 Battery

  Double the storage in one unit, for a house on a time-of-use tariff charging overnight.

• Sunsynk Battery Wall Mount Bracket

  Hangs the battery on the wall beside the inverter instead of standing it on the floor.

• Sunsynk SDM120CT-M Single-Phase Meter

  Where the DNO asks for export limiting under G100, the meter does the job the supplied CT clamp cannot.

• Sunsynk Klik Device

  Runs two different batteries on one inverter – useful when adding storage later to a battery that is no longer sold.

Alternative sizes

Sunsynk build the ECCO SG04LP1 at 3, 3.6, 5 and 6 kW, all single phase on 48 V batteries and all sharing this case, manual and app. We stock the 3.6 kW and the 5 kW. The 3.6 kW on this page is the largest that stays inside G98; from 5 kW up a G99 application has to be approved before the installation goes in.

• Sunsynk 5kW ECCO Hybrid Inverter

  The step up in the same range: 5 kW out, 22.7 A rated, 40 A passthrough, G99.

Outside the ECCO range, the single-phase Sunsynk Acure 3.6 kW, Acure 5.0 kW and Acure 8.0 kW cover the same job in a newer case, and the 8 kW goes further than the ECCO does. This inverter is also sold ready-paired with storage as the 3.6 kW and 5.12 kWh package.