How Do I Know If I have A Neutral Wire for Automated Switches

How Do I Know If I have A Neutral Wire for Automated Switches



How Do I Know If I Have A Neutral Wire?

Most INSTEON-compatible wall switches and dimmers require a neutral wire connection to operate. While all houses have a neutral wire, the real question is "Do I have neutrals in my switch boxes?"

To answer this question, here are some guidelines:

  • If your house was built in the mid-1980s or later, there is an excellent chance that you have neutrals everywhere in your home
  • If there is an outlet (wall receptacle) near the switch, most likely that switch box has a neutral
  • Switches that are ganged together have a much higher likelihood of having neutrals, no matter what year

Checking The Switch Box

If you are unsure whether or not you have neutrals, look in your switch box. Please observe all safety precautions before handling the electrical wiring in your switch boxes.

  • Turn off your breaker box
  • Take off the trim plate over the switch
  • Remove the screws from your switch and pull out the existing switch to look at the wires
  • If you see a white wire (or group of them), it is VERY likely that you have a neutral in that switch box

The only way to be absolutely sure that you have found a neutral wire is to check the voltage (110V/120V) between the white wire and the "hot" (usually black in color) wire in the box. In a standard switch/dimmer, the "hot" is using one of the two wires connected to the switch.

Standard Switch Wiring
Standard Switch Wiring
Most INSTEON Switch/Dimmer Wiring
Insteon Switch Wiring with Nuetrals

What To Do If You Don't Have Neutrals

For all incandescent applications use the SwitchLinc 2-Wire Dimmer. This switch does not require a neutral connection but note that it is for use with incandescent lighting:

SwitchLinc 2-Wire Dimmer
SwitchLinc 2-Wire Dimmer
SwitchLinc 2-Wire Wiring
SwitchLinc 2-Wire Wiring Illustration


INSTEON LED BulbIf you don't want to replace a switch, you can now simply replace your light bulbs with the INSTEON LED Bulb. Now you don't have to worry about re-wiring if you don't have to. Simply leave your wall switch in the On position and control the INSTEON bulb from any INSTEON controller.

Get An Expert

When in doubt, hire a pro to find out if you have neutral wires in your switch box. If necessary they can "pull" neutral wires wherever you need them.

What About Using the Ground Wire If You Don't Have Neutrals?

While it is true that the ground wire and the neutral wires connect to the same place in your circuit panel, it is NOT acceptable by building and electrical codes to use the ground wire in this manner.