Installing Fibaro Dimmer 2

The Fibaro Dimmer 2 is a smart Z-Wave module that allows you to dim and control your lighting wirelessly via your home automation system. This compact in-wall dimmer fits behind an existing wall switch and supports both trailing-edge and leading-edge dimming. In this guide, we’ll walk you through how to install the Fibaro Dimmer 2, what tools you need, and what to keep in mind for a safe and successful installation.

What you need before installation

Before you begin, make sure you have the following components and tools:

• Fibaro Dimmer 2 module (FGD-212)
• Flush-mounted wall box (minimum 50 mm depth recommended)
• A Z-Wave home automation system (e.g. Home Center, Homey, SmartThings)
• A compatible wall switch (momentary or toggle)
• Dimmable lights (halogen or dimmable LED)
• Screwdriver, voltage tester, and wire connectors if needed

Note: The Fibaro Dimmer 2 can be used with or without a neutral wire. This makes it suitable for older installations, as long as the connected load meets the minimum requirement (at least 25W). However, using a neutral wire is highly recommended, especially for LED lights.

Wiring the Fibaro Dimmer 2

The module has several terminals. Here is what each one is for:

• L: Line input (live, brown)
• N: Neutral wire (blue) – optional but recommended
• S1: Input for the main switch
• S2: Optional second switch or scene control
• O: Output to the lamp

Basic wiring with neutral wire:

1. Connect the brown live wire to terminal L
2. Connect the blue neutral wire to terminal N
3. Connect the black wire going to the lamp to terminal O
4. Connect the switch wire to terminal S1

Without a neutral wire: You can connect the dimmer without using N, but this may require a higher minimum load and is less reliable with low-wattage LEDs.

Installation and pairing

Once the wiring is done, carefully place the dimmer behind the switch inside the wall box. Turn the power back on and check if the light responds to manual switching.

Pairing with your Z-Wave controller

1. Put your Z-Wave hub in “add device” mode
2. Quickly press the switch connected to S1 three times
3. The controller should detect and add the Fibaro Dimmer 2

You can now rename the device in your smart home app, assign it to rooms, and configure advanced settings such as dimming behavior and scene triggers. The module also measures power usage and supports multi-click actions on S1 and S2.

Common mistakes and useful tips

To ensure a trouble-free installation, keep these points in mind:

• Only use dimmable bulbs: Non-dimmable lights can flicker or be damaged
• Check minimum load: Too low wattage may cause flickering or non-functioning
• Prefer momentary switches: These provide better compatibility and enable scene control
• Perform calibration: The module calibrates automatically but can also be triggered manually through Z-Wave commands
• Allow enough space: Use a wall box that is at least 50 mm deep to comfortably fit the module

The Fibaro Dimmer 2 is a powerful and flexible solution for smart lighting. With support for both neutral and 2-wire installations, it’s one of the most versatile modules available. When installed correctly, it allows for seamless integration into your smart home while maintaining full manual control.