Installing a 2-Way Dimmer Switch in the UK: A Step-by-Step Guide

The ultimate convenience for your home lighting system, a two-way dimmer switch is an ideal choice for creating ambience and maintaining energy efficiency. Not only can it supply a range of lighting levels throughout the day and night, but it can also offer separate control from two switches. Whether you’re fitting a new unit or upgrading an existing one, here we explain how to install a two-way dimmer switch in the Uk – with a wiring diagram to help.

Choosing the Right Switch

Before tackling this DIY project, the first thing you’ll need to do is work out the correct type of dimmer switch for your lights. Generally speaking, the switch selected should be enough to match the wattage of the bulbs it’s going to be controlling. To ensure that you purchase the right switch look at the manufacturer's label on the lamp or light fitting you intend to control, which will normally have the equivalent wattage stated.

As a rule of thumb, the wattage should never exceed the maximum wattage for which the 2-way dimmer switch is rated, otherwise the unit and/or the bulbs may overheat. When selecting the switch type, always allow for future and possible changes, such as the use of different bulb types or wattages and buy a dimmer switch with a higher wattage rating than you actually need. Once you’ve chosen the type you need, take note of the position of any pips, as this is integral for when it comes to wiring the 2-way dimmers.

Standard Dimmer Wiring Diagrams

To wire a two-way dimmer switch, you’ll need to refer to your chosen switch’s wiring diagram. This type of switch will usually have at least five connections to make. The following standard diagrams will provide you with an insight into the basic wiring connections required.

Two-Way Dimmer Switch with Neutral Connection

Two-Way Dimmer Switch with No Neutral Connection

Connecting the Switch

Once you’ve got a good understanding of the wiring diagram and are confident of the connections to be made, you’re ready to get started with actually wiring the switch. Excavate the walls to prepare the cables and ensure that the inside of the box is clean and tidy. Then, strip back the insulation on the cables and connect them to the wiring posts on the dimmer switch, using either screws or push-fit terminals, depending on the type of switch you’re connecting. Typically, you’ll have three connections - two for the feed cables and one for the loop cable. Just make sure that the same coloured wires are connected together, in accordance with the wiring diagram.

Testing & Installation

When all the cable connections are secure and safely tucked away, fit the backplate and check your wiring against the manufacturers wire diagram before switching on. If the switch turns off and on correctly and no errors show up, you’re good to go. Fit the faceplate and screw fixings to the wall and keep an eye out for anything that seems unusual or if there are any sparks when switching the lights on or off. If this is noticed immediately switch off the mains and begin checking the connections again.

Finally, you can put everything right and test both switches and make sure that they’re turning the lights on and off properly. To help with this, make sure that you turn on your lights using both the dimmer and the switch, then tweak the dimmer settings until the results are satisfactory.

Final Thoughts

As with most electrical jobs, to ensure safety, it’s best to refer to best practice safety guidance or hire a professional with the skills necessary. But, if you’re feeling up for a challenge and can stay focused and safe, installing a two-way dimmer switch should be perfectly achievable. With good preparation and the right tools to hand, this practical and decorative addition to your home lighting will bring an extra level of ambience to your home.

Wiring Fibaro Fgd211 To Two Way Circuit Uk Connected Things Smartthings Community