Hello, I am in the process of replacing all the light switches in my home.
Some of the old switches have the 2 wires connected and some have three. The
switches I bought have only the 2 wire connectors for hot and cold wires.
What do i do if the outlet has the 3 wires? Are there switches that have the
ground on them as well, to accomodate 3 wires in the outlet?
Yes, they are called "3-way" switches, used when you want to be able
to turn the switch on/off from two locations. When you get into more
than two locations you will need one or more "4-way switch(es)" in the
When replacing, be sure to wire the new switch identically to the old
Do a Google search on "3 way switch wiring" for the operating
principles and wiring options.
Be sure you find the 'common' terminal on the old 3 way switches and mark
the 'common' wire with a piece of tape or something before disconnecting the
wires. The 'common' terminals may not be in the same phyical postion on the
old and new switches. BTDT... The common termininal screw is usuaally
marked in some way such as dark color.
Note that some switches do have a green grounding screw on the yoke which
would add one wire to each type of switch.
I second the labelling of the common wire. The original 3 way switches in my
home do not match the physical configurations of any of the new switches
that I have purchased. The first time that happens turn a 5 minute
replacement job into quite an adventure of discovery!
I totally think you are radically over your head, brah!
But - if you are talking about a switch, and NOT an outlet, and NOT a
switch which has an outlet beside it, try this:
1) Go to the hardware store, by a switch labeled "3 way".
2) Shut off power. In this case, I recc. you kill the main.
3) Connect the black wire to the black colored screw on the switch.
4) Connect the red wire to one of the brass screws on the switch
(either/or, makes no difference).
5) Connect the white wire to the remaining brass screw.
6) Turn power back on.
7) If a breaker pops when you turned the main back on, or if a breaker
pops when you flip the light switch, STOP, go to step 8.
8) Call an electrician.
As I said find the wire that is connected to the black scew terminal on the
3 way switch and that will be your common. The other 2 wires can connect to
the switch in any order.
There is no standard for which color wire is used for what in 3 or 4 way
circuits. If you have lost track of the common then you will have to open
each box, switches and light(s), and diagram/ figure out how they did it.
If that is the case then get some help or a book as there are several
different ways to wire a 3 way circuit.
Note that the ground wire if there is one is either bare copper or green.
Electrical work of this sort is easy. But you gotta know the basics.
You get it wrong , you start an uninsured fire or hurt someone. It
only takes a couple of hours of study to know whats what.
Go to home depot, buy:
1. a book on electrical wiring ( I liked Ortho books in the past)
2. a cheap circuit tester ( has 2 leads tells you if something is hot
3. Good three way and single pole switches ( rated for commercial use,
they have a metal yoke down the bac, cost about a buck more than the
cheap 49 cent ones).
Read the parts of the book that apply to your situation ( lighting
circuit wiring ). Figure out what you are going to do before you take
Kill the circuit at the panel.
Test the circuit at the switch to make sure its dead
Do your wiring as per instructions in the book. Make sure you twist the
wires on the screws so that they just get tighter as you tighten the
screws. Make sure there is no way a bare wire can ever touch anything
other than the terminal screw.
Put it all back in the box tighten it down, inspect again to make sure
you did not botch it.
Turn circuit back on and test.
This is easy when you have done a little research.
The most important thin
<< What do i do if the outlet has the 3 wires? >>
A duplex outlet with three wires will commonly have one switched connection and
one always on. The tab between the two brass screws will be removed.
Switches with three wires are likely to be three-way switches and will be
supplied with red, black and white leads.
Consider finding some expert help with your project. Based on your
unfamiliarity with ordinary wiring you could have some unpleasant unplanned
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