Neutral Wiring


I’m doing renovations to my house and requested electrician to pull a new neutral wire to individual switch, but i’ve few questions as following:

  1. Electrician suggested to pull a new neutral wire from electric box to switch directly (without connect any lights). Does this work properly with smart control? or the neutral wire must pull from existing lights back to switch?

  2. Does neutral wire can share to more than 1 switch box. e.g. after i pull a new neutral wire from electric box to switch (3 gang), can this neutral wire share to another switch box beside current one (for save cost).


Neutral is Neutral. Electrically it doesn’t matter where it comes from. Personally I prefer neutral to come from the same place as the live, but that can be more work and expense to do if re-wiring. Also be careful with neutral in lighting circuits as often the neutral ‘coloured’ wire is used as a live return and many people do not mark it properly.

This is one of the reasons I like the Fibaro dimmers as they don’t need a neutral.

Thanks for answer. My LED doesn’t support dimmer so that neutral is only way. In that case my electrician can just proceed with totally new neutral wire from electric box.

Btw, any idea that one neutral wire can share with multiple switch?

You can configure the Fibaro dimmer as in on/off mode.

Yes, neutral can be shared.

Good to know that. Thanks simon

Does that mean it could safely be used in on/off mode with fluorescent tubes and no neutral?

As an add on, and to get further clarification, here is my particular scenario. I have two light switches that share a wall box but are on two separate circuits. I have to flip two different breakers to kill them both. One runs the lights in the bathroom and one runs the ceiling light in the hall out side. The switch for the bathroom light is a power through fixture installation, the light in the hallway is a power through switch installation. I want to automate the lights in the bathroom but there is obviously no neutral wire. In this instance would it be possible to safely jump a neutral line from the hallway switch to an automated switch for the bathroom?

These are 230V only, though, and not available in The States as a result, yes?

Given that they’re on separate circuits (and I’m assuming they’re not two phases of the same 220 circuit), you are creating a situation where the return wire could carry as much as the rated amperage of both, which is pretty dangerous. If the circuits were, say 15A, that would be 30A total. If your wiring is 14 gauge, it’s only rated for 15A, so this would be a significant fire hazard. I wouldn’t do it.


Understood. Thanks for the help!