---
title: Fronius
description: "## Introduction Fronius inverters can be connected to the Qilowatt system using a Modbus module. This guide explains the necessary settings, module installation, and startup steps. ## Prerequisites • The inverter is operational and configured according to the manufacturer’s instructions…"
url: "https://docs.qilowatt.eu/en/docs/fronius/"
updated: "2025-10-30"
category: "3. Inverter Installation - pick the right one"
tags:
  - fronius
  - installation
  - inverter
  - modbus R2
---

# Fronius

## Introduction

 Fronius inverters can be connected to the Qilowatt system using a Modbus module. This guide explains the necessary settings, module installation, and startup steps.

## Prerequisites

 • The inverter is operational and configured according to the manufacturer’s instructions
• A Modbus R1 or R2 module is available
• Required tools and a communication cable (CAT5 or CAT6)
• A Qilowatt account has been created and the app is ready for adding devices → [Creating a user account](https://docs.qilowatt.eu/en/docs/creating-a-user-account/)

## Step-by-step Guide

### Configuring the inverter in the Fronius web interface

 **1.** Open the **Fronius web interface** and go to the **Modbus Data Export**view.
**2.**Configure the following settings:
• **Modbus RTU Interface 1:** slave
**• Baud Rate:** 9600
**• Parity:** none
**• SunSpec Model Type:** int + PF
**• Inverter Address:** 3
**• Inverter Control via Modbus:** On

### Installing the module

 **1.** Install the **MODBUS R1 / R2 module** according to the installation manual.
**2.**Connect the communication cable (CAT5 or CAT6) between the module’s RS485 port and the inverter’s Modbus port:
• **M1+ → A**
• **M1- → B**

### Starting the module

 **1.** Switch on the circuit breaker of the MODBUS R1 / R2 module (or insert the fuse).
**2.**Check if the module’s **white LED indicator** starts flashing rapidly.
**3.** Connect the module to your home WiFi network → [Connecting the device to WiFi.](https://docs.qilowatt.eu/en/docs/connecting-the-device-to-wifi/)
**•** Place the module where the WiFi signal is strong.
• Use a WiFi range extender if necessary.

## Result

 The Fronius inverter is successfully connected to the Qilowatt system. The Modbus module transmits data and enables device control and energy optimization.

## If it Doesn't Work

 • If the LED indicator does not light up, check the connections and circuit protection.
• If communication does not work, verify that the Modbus settings in the web interface are correct.
• If the module does not connect to WiFi, follow the guide → [Resetting WiFi settings](https://docs.qilowatt.eu/en/docs/resetting-wifi-settings/).
• If the issue persists, contact our team: [support@qilowatt.eu](mailto:support@qilowatt.eu).