TSUN + Fronius Wattpilot

What Zerofy can do with TSUN and Fronius Wattpilot

In practice

• Zerofy adjusts the charging current of your Wattpilot but doesn’t switch phases. On a three-phase connection, solar charging needs at least about 4.1 kW of surplus (6 A × 3 × 230 V); on a single-phase connection about 1.4 kW.
• Many TSUN systems are small (typically 0.8–3 kW). A balcony system rarely produces the 1.4 kW needed to start charging, so solar charging works best with larger TSUN installations; Smart mode can still move charging to the cheapest hours.
• Zerofy gets new TSUN data every 5 minutes and adjusts accordingly. A minimum runtime and an activation threshold in Autopilot keep passing clouds from interrupting charging.
• If your car is connected to Zerofy too, turn on Autopilot for either the car or the charger, not both.
• In its own surplus mode the Wattpilot starts at 1.38 kW on one phase, adjusts in 0.23 kW steps and switches to three phases above 4.14 kW, where it steps in 0.69 kW; the switching level can be changed in the app. Via OCPP, Zerofy sets the charging power but not the phases, so the minimum is 6 A: about 1.4 kW single-phase or 4.1 kW three-phase.

What TSUN and Fronius Wattpilot offer on their own

TSUN: TSUN offers no EV charger and no surplus-charging function. An 800 W balcony system also stays below the about 1.4 kW a charger needs at its 6 A minimum.

Fronius Wattpilot: The Wattpilot’s own PV surplus charging needs a Fronius inverter (GEN24, Verto, or SnapINverter/IG with Datamanager 2.0) with a Fronius Smart Meter at the feed-in point, talking over the Solar API in the same network. Other inverter brands only work with an extra Fronius Smart Meter IP or Datamanager Box 2.0 plus Smart Meter; the Wattpilot then also appears in Fronius Solar.web.

Zerofy connects the two: it reads TSUN production and controls your Wattpilot to match, together with your other devices in one app, with dynamic tariffs and forecast-based Smart mode.

Setting up TSUN and Fronius Wattpilot in Zerofy

1. Connect TSUN

Zerofy connects to the TSUN cloud with your TSUN Smart login and reads your inverter data.

1. Register your system in the TSUN Smart app.
2. In Zerofy, add an inverter, choose TSUN and log in with your TSUN Smart credentials.

Good to know: Only TSUN Smart accounts work (inverter IDs starting with Y); TSUN Home accounts are not supported. Battery and meter data are only partly available, depending on the system.

Step-by-step guide for TSUN

2. Connect Fronius Wattpilot

The Wattpilot connects to Zerofy via OCPP 1.6J; you enter the connection details from Zerofy in the Solar.wattpilot app.

1. In Zerofy, add a Fronius Wattpilot and copy the OCPP connection details.
2. In the Solar.wattpilot app, go to Internet → OCPP and enter the details.
3. Save and wait until the status shows the connection is established.

Step-by-step guide for Fronius Wattpilot

3. Turn on Autopilot

In Zerofy, open your Wattpilot, turn on Autopilot and choose Solar – or Smart to also use dynamic tariffs and forecasts. Set the priority, activation threshold and minimum runtime.

Dynamic tariffs

Zerofy can also run your Wattpilot on dynamic electricity prices (EPEX Spot or Nord Pool, e.g. Tibber or aWATTar) or on a fixed time-of-use tariff. Smart mode combines those prices with forecasts of your household consumption and your TSUN solar production.

Learn more about Smart Mode

About TSUN and Fronius Wattpilot

TSUN – TSUN (TSUNESS Co., Ltd., Suzhou, China, with a German office in Frankfurt) makes microinverters from 300 W single units to 3.3 kW 6-in-1 units. In Europe it is mainly found in 800 W balcony systems such as the TSOL-MS800, often combined with TSUN balcony storage (MSU2000, MSU4000Elite). Monitoring app: TSUN Smart.

Fronius Wattpilot – The Wattpilot is the EV charger of the Austrian inverter maker Fronius, built for solar charging with automatic 1/3-phase switching and surplus charging from 1.4 kW. The Flex has LAN and Wi-Fi, a §14a input and a Pro version with MID and Eichrecht; it is mainly sold through installers. Products: Fronius Wattpilot Flex Home, Wattpilot Flex Pro, Wattpilot Go, Wattpilot Home.

Manufacturer information last checked: October 2026.

All devices that work with TSUN