The neutral wire provides the return part of the single-phase circuit. Current flows in it - the same current as in the phase wire. If you don’t connect the neutral, the circuit won’t work. The neutral isn’t needed in a three-phase connection, the return current flows in one of the other two phase wires.
As the neutral point of an electrical supply system is often connected to earth ground, ground and neutral are closely related. Under certain conditions, a conductor used to connect to a system neutral is also used for grounding (earthing) of equipment and structures.
The most common requirement of any hardwired automated light switch is a neutral wire. Yes, there are a few…(read very, very, very few) switches that don’t require a neutral, but those will limit you to incandescent only. For those of us using LED, Fluorescent or some other energy efficient bulbs under 20w a neutral is REQUIRED!
Option 1 - Run a Neutral Wire. If you want to use smart switches and don't have a neutral wire in your switch box, you can hire an electrician to run a neutral wire between the light fixture and the switch. You can also have an electrician rewire the switch and light fixture, which is potentially more expensive.
Some manufacturers get around the "no neutral" problem by using the ground wire as a substitute. Such an example is the ODS10 by Leviton. The instruction manual even makes it clear that the occupancy (motion) switch WILL NOT WORK without connecting the ground wire. No ground wire connected means no power to the switch's motion sensor.
The Purpose of the Neutral Wire. The following will provide an explanation for the purpose of the neutral wire and the the difference between the ground wire and the neutral wire. United States Home Electrical System The typical home electrical systems here in the United States uses what is known as AC, which stands for Alternating Current.
For household AC current, why do we need 2 live, a neutral and a ground 4-wire connection? We get 3 wires from the street transformer where the Secondary coming towards home has a middle tap. The phase difference from either one end to the middle tap of the Secondary is 120 volts, and end-to-end 220 volts.
Why Smart Switches can't be used without neutral. One of the most common questions we get is "Why are there no Z-Wave On/Off switches that work in a 2-wire system", or "Which relays can I use without neutral".
The only time a neutral is required is for 120 volt circuits, either stand alone or built into a 240 volt appliance. Heating elements and motors can run on 240 volts and not require a neutral. Some motors can be wired for either voltage. Either way they require 2 wires to run them, line and line or line and neutral.