What is a Shelly Bypass Used For And Why Do I Need One?

With the recent introduction of the Shelly 1L to the Shelly Home Automation range, you may have noticed an add-on that is available specifically with the Shelly 1L called a Shelly Bypass. We sell the Shelly Bypass in the store as a standalone product or as an add-on with any Shelly 1L or Shelly Dimmer 2 devices, but what actually are they and do you need one?

The great thing with both the Shelly 1L and Shelly Dimmer 2 is they work without the need of a neutral line. That's great news for us here in Australia if you are wanting to add a Shelly device behind a light switch, where typically we do not have a neutral wire.

What is a Shelly Bypass?

A Shelly Bypass is required where there is no neutral wire and where the power consumption is less than 20 watts. If the load of the light is very low (typically, LED lights), you need to add some form of load, that's where the need of a bypass comes in!

Rather than turning off the light, the Shelly 1L and Shelly Dimmer 2, dim the light so low, it stops glowing, leaving a very small current flowing through the circuit of the Shelly Device to keep it running, even when the light is off.

Do I need a Shelly Bypass?

Most LED lightbulbs in Australia are under 20 watts. The Shelly 1L or Dimmer 2 require a minimum load to be able to power the module so if you are below this value then you will need one.

If you are using the Shelly 1L or the Shelly Dimmer 2 in a place with no neutral wire (such as behind a light switch) and you live in Australia, yes you most likely do.

Where do I install the Shelly Bypass

If you are installing a Shelly Bypass in a lighting circuit in Australia, you will need to attach the Shelly Bypass between the Output wire going to the lightbulb and the neutral going to the other side of the lightbulb. It will feel very unnatural to connect the wire this way. Most people in Australia have a ceiling rose or light fitting which allows...