Installing a dimmer switch

flavio

Diamond Member
Oct 9, 1999
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I just replaced an old dimmer switch that broke with a new one. The new one had a green ground cable and there is no easy place to put the ground wire. So I wrapped it around the screw that holds the switch to the metal box behind.

Is that safe? It works, but I don't want anyone to get shocked.
 

BillGates

Diamond Member
Nov 30, 2001
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Grounding to a metal box is the best way to ground electrical devices - providing that they are interconnected via conduit - which means that eventually they'll ground out on your grounding rods, underground.

That's a lot of grounding.

How old was the wiring in the switch box that it didn't have a ground wire to splice to?
 

Brutuskend

Lifer
Apr 2, 2001
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OH are we talking about a car dimmer switch or a dimmer for a overhead light fixture?

(I thought you were talking about a headlight dimmer switch)

Either way, a bad ground will not shock you. But I would be much more carefull if it's house wiring!
 

BillGates

Diamond Member
Nov 30, 2001
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Originally posted by: Brutuskend
No one will get shocked.
At worse it will just stop working if it comes loose.

Definitely not true - switches don't need a ground wire to operate and will not stop working if the ground wire came loose... It may become a safety hazard and would no longer meet electrical codes, but would be no worse for the wear.

Take a look at wiring in an older home sometime, you'll be shocked that the place didn't burn down the first day it was powered up!
 

Brutuskend

Lifer
Apr 2, 2001
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Definitely not true - switches don't need a ground wire to operate and will not stop working if the ground wire came loose... It may become a safety hazard and would no longer meet electrical codes, but would be no worse for the wear.

I was taking about auto wiring.

Your right about house wiring.
 

flavio

Diamond Member
Oct 9, 1999
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Ok, it's a house switch in my bedroom. What are exactly the dangers in working on home electric?

This is a very old house and didn't have a ground wire. The heat in this place comes from one huge vent in the floor of the living room. You can certainly (people have) burn your feet on it. If you want heat upstairs you can turn another floor vent on with a weird key that we keep on a doorknob.

I don't trust the electric.
 

Brutuskend

Lifer
Apr 2, 2001
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Ok, it's a house switch in my bedroom. What are exactly the dangers in working on home electric?

You can DIE!

If you are unable to shut off the power while working with the elect. a good way to be safe (ER) is to ALWAYS keep one hand in your back pocket!

The way people die messing with electricty is the juice will go up one arm, across your chest, and then back to ground through your other arm. (STOPPING YOUR HEART)

If you keep one hand in your pocket, the juice will not go to ground, or atleast not through the same path.
 

GarlicBreath

Senior member
Jan 11, 2002
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Originally posted by: Brutuskend
Ok, it's a house switch in my bedroom. What are exactly the dangers in working on home electric?

You can DIE!

If you are unable to shut off the power while working with the elect. a good way to be safe (ER) is to ALWAYS keep one hand in your back pocket!

The way people die messing with electricty is the juice will go up one arm, across your chest, and then back to ground through your other arm. (STOPPING YOUR HEART)

If you keep one hand in your pocket, the juice will not go to ground, or atleast not through the same path.

I prefer to keep one hand on my willlie instead. I might still die, but it would look really cool if I died with sparks shooting out of my meat puppet. It would be like super force lightning, or something. Who's the master now, Yoda?
 

flavio

Diamond Member
Oct 9, 1999
6,823
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Originally posted by: Brutuskend
Ok, it's a house switch in my bedroom. What are exactly the dangers in working on home electric?

You can DIE!

If you are unable to shut off the power while working with the elect. a good way to be safe (ER) is to ALWAYS keep one hand in your back pocket!

The way people die messing with electricty is the juice will go up one arm, across your chest, and then back to ground through your other arm. (STOPPING YOUR HEART)

If you keep one hand in your pocket, the juice will not go to ground, or atleast not through the same path.


I'll do that...or maybe I'll use the willie method. I shut the power off to the room at the fusebox though. This place is just old though.

 

Jerboy

Banned
Oct 27, 2001
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Originally posted by: flavio
I just replaced an old dimmer switch that broke with a new one. The new one had a green ground cable and there is no easy place to put the ground wire. So I wrapped it around the screw that holds the switch to the metal box behind.

Is that safe? It works, but I don't want anyone to get shocked.

Is the box grounded?

If so this is ok, but I'm not sure if it's quite par with the NEC. You don't have to have ground connected for functionality, but it's dangerous. If it is grounded and something goes wrong, the ground shorts out the circuit and trips the breaker instead of putting the exposed screws to line voltage. Use it ungrounded. but use a plastic screw to affix the cover plate. Should the dimmer ever short to it's case, plastic screw won't shock you.

This will work.... but I don't know if you meet the code.
 

Squisher

Lifer
Aug 17, 2000
21,204
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If the existing wiring in your house is a two wire system there is little you can do to provide ground without running a whole new run of wire. You would not be violating code to install a dimmer without the ground in this instance.
That being said, it wouldn't hurt to try and convert as much as you can to a 2 wire plus ground system. The ground may save your life.