Standard Way To Wire Lighting Circuits

robertc65

I have been reading about the new Insteon dimmer switches at Smarthome.com. It says they require a Neutral. I have seen quite a few switch boxes fed with say 14/2 leaving no wire for a neutral. Is there a standard way these days on how to wire lighting circuits. Should there always be a netral in the box. What about 3 way or multiple 4way circuits should there be a neutral in all those switch boxes.

Thanks in advance

Rob

ATS

A neutral isn't required in switch boxes.

robertc65

Thanks for the reply. What about connecting the neutral of an electronic dimmer switch to ground instead of the neutral wire if there is no neutral in the switch box. I believe the only current flow would be to power the electronics in the module ( 10 watts or so at the most). The load from the light would still go through it's own neutral.

Also in general are multi-way switch circuits wired so that a neutral would exist in each switch box? I'm just wondering once I start installing these modules in friends houses and such how likely I will run into switch boxes without a neutral. All of the houses I would install modules into would be new, say 5 or 10 years old at the most.

Thanks

Rob

stars13bars2

An electrician that doesn't know the standard way to wire a light switch, but seems to be up on the DIY way, should invest heavily in liability insurance. I love this Contractor Talk. " Git er Done"

ATS

All I really should say here is "NEVER make a neutral to ground connection anywhere except at the main disconnecting means". Please for anyone who comes after you, plumbers included, could be killed if you do this.

steveprichard

Very seldom will you see a neutral in a switch box. Occasionally I've seen a wire nutted neutral in a 2-gang switch box that at one time had a receptacle.

A bare ground wire should never be used as a conducting wire, which is what the dimmer would be doing.

I've seen several melted receptacles with a ground attached to neutral side. They were so distorted, I could not tell if it was a loose connection or just the smaller wire with no insulation that caused the heat.

I'd be willing to bet that this is a MAJOR cause of electrical fires.

__________________
Steve

"Keep thee thy airspeed, lest the earth rise up and smite thee!"

robertc65

I'm Glad to be your source of Entertainment. I'm not a professional, but my body count is quite low considering. Seriously though, I don't plan to run out and Tie the Neutal wire to ground in a bunch of houses.

I had always heard this should never be done but never really gave it much thought as to why. There are a lot of things we should never do, but that does not always stop us. I feel the best way to manage risk is to understand the risk as opposed to just fearing it.

I know the reason a ground is used in the 1st place but in most newer houses built in my area you wont't find a metal box or a pipe that's not some sort of plastic. It seems that in most cases the ground wire really has no purpose any longer. What I was really looking for is a technical explaination as to the risk in connecting a ground to the Neutral. I certainly don't want to put anyone in danger. I respect electricity and always make sure I wire things in a safe manner.

I spent some time thinking about this issue while riding in the car over the weekend and came to the conclusion that touching a grounded metal pipe or some other grounded metal object while also touching the ground wire that was tied to neutral should not cause any current flow. This would be the case if the ground was connected, however if one were to disconnect this ground and get between it, you would become the shortest path to ground. Being a ground wire, no one would suspect this thus you are setting a trap for someone in the future as mentioned in previous posts. Does this make any sense or am I off the mark.

Again. I'm not planning on doing this I just want to better understand it.

Thanks

Rob

steveprichard

Rob,

You need to know that a neutral wire is grounded. Yep. In your panel, the neutral bus bar is grounded. It's a grounded CONDUCTING wire. When a load is put on a hot and neutral, current is flowing through them. A ground wire is not made for conducting. Ground wires are usually smaller and not insulated.

__________________
Steve

"Keep thee thy airspeed, lest the earth rise up and smite thee!"

RobertWilber

The Insteon dimmers require a neutral and a ground connection
So say their specs and drawings
If you plan to use them, I guess you just have to wire that way
There are often neutrals in switch boxes, if they are wired feed-thru
If they are switch legs with only the hot in and return in one cable, I guess you're out of luck and would have to rewire that switch location so it has a neutral available

...and talking about bare wires as conductors, have you ever found some wizard using 14/2 with ground as a three-way cable? Bad enough using the black and white as travelers [illegal], but I stumbled across some rocket scientist using the GROUND WIRE as a traveler conductor!

robertc65

Yes I have run into travelers that were White and Black, but I never trust what wire is what based on color. I always get out the meter and confirm. The ground however, I would never think to check. I would always assume it's just ground and nothing else. I agree I will certainly run into some switch boxes that are going to need some new wires fished in.

Thanks

Rob