Skip to content
US Express $10 Delivery. Shipping Zigbee & Z-Wave (US 908.42)

Understanding 2-wire Lighting

You'll often see us refer to 2-wire and 3-wire lighting systems, it can be a confusing description and is one of the most common questions we get.

So why's this important?

It's important because not all products work in a 2-wire system, so knowing which type of lighting system you have is important so that you select the right products, For instance many products, such as relays, can't work if installed into a 2-wire system.

The obvious question I can hear on your lips is - what's the difference?

The simple explanation is that a 2-wire system does't include a Neutral wire at the light switch, whereas a 3-wire system does include the Neutral at the switch. The 2-wire system is by far the most common in the UK and many parts of Europe.

To make this easier we've added new icons on the relevant pages to highlight which system the product is suited to. Just look out for the icon and you can't go wrong!

2-wire icon Works in a 2-wire system, it does not need a Neutral connection. 3-wire Icon Works in a 3-wire system, a Neutral is required.

We've also written a new application note to explain the differences between the two systems and help you understand which you have in your home - Application Note 23: Understanding 2-wire and 3-wire Lighting Systems.

Hope this helps you.

See you soon.


Author David Bell

About the Author

David Bell is the founder of Vesternet. As a contributing author on popular smart home topics including Z-Wave & Zigbee, he’s been cited in a multitude of popular websites, forums & articles over the past 10 years and continues to publish regularly on Vesternet.

With over 25 years in business, and 15 years in home automation, he also heads up all of Vesternet’s commercial initiatives throughout various online channels as an expert in sales, marketing & growth strategies.

Previous article My First Month With Robomow...