how do i wire a 3way switch?

This is a partial solution it is the understanding - some knowledge symbols needed - find yourself two common batteries of 1.5 volts each ... using cellotape and old wire join these together to make a 3 volt battery. Now using a 3 volt bulb cellotape that together with wires. Now make a ring circuit with the battery and bulb and note that the bulb comes on. You now a tool to test the action of switches.
Try to build this circuit testing it bit by bit - test the switching using the battery and bulb. Draw the circuit out / the dashes are wires and the o are terminals in switches but completely ignore the dots.

...........o---------o........o--------o
A----o----................X.............----o------B
...........o---------o........o--------o

Ok test the switching between A and B
X represents a cross over in the wiring of the switch.
When you have it correctly working click any switch to change the state of the bulb between off/on and on/off.
Once you understand how the switching works you are on the way ...
As has been stated - it is one thing to understand but another to do!

Nyge
March 2011

Steve,
I think you are mistaken. I have a three-way switch for my hall lamp; I can switch the lamp on or off from the landing, the middle of the hall or by the front door. This circuit uses 'normal' mechanical (i.e. not solid state electronic) switches.

There seems to be some confusion about the defifnition of a three-way switch. I always understood a lamp controlled by two switches as a two-way switch. However, most wiring diagrams on the web seem to show two switches for a 'three-way circuit' and describe a circuit with three switches as a 'four-way' switch! Whatever!

This link shows both, with videos:

http://www.askthebuilder.com/B141_3_Way_Switch_Wiring_Diagram_and_4_Way_Switch_Wiring_Diagram.shtml

As an Engineer, the only schematic I can reason out is the standard 'parallel wires with a switch at each end' diagram with a third, double pole switch in the middle that either 'completes' the two wires in isolation or 'crosses' them. Think about it this way; the two parallel wires A and B have ends A1 and A2 on wire A, and B1 and B2 on wire B. The middle switch would either connect A1 to A2 and B1 to B2 or in the other position, connect A1 to B2 and B1 to A2. It sounds confusing, but is pretty straightforwards really.

Either way, the switch you seem to be describing DOES exist and, speaking from personal experience, is really useful!

All the best,

Phil
November 2008

Do you mean a 2 way switch there is no such thing as a 3 way switch.

Do you mean a 3 GANG switch.

Do you mean a 2 way switch wth an intermediate making 3.

regards

Steve

Steve
March 2008

by three way i take it you mean a 3gang 1way switch? if so then there are a number of ways.. you can take a common(live)cable to the switch and link all your commons at the switch together then your switchlive cables are taken from your switch ie.. 1st switch of your 3gang put in L1 this goes to your first light you want to serve. next switch the middle one connect your next switchwire to L1 of that switch that goes to your next light then repeat as before for your third light

andy gibbons qualified 16th edition electricain
March 2008

Go to google & type in 3 way switch diagrams there are a variety of ways to do it. Depending on how many lights etc. But basically you need to feed from the light a two wire to one of your switches and another 3 wire to the same switch that will travel through the wall between the two 3 way switches. The hot wire (with power) from the light goes too the bottom screw of the side of the switch with only 2 screws. Both of the neutral wires normally the white are twisted together with a marrette. Put the black wire around the upper screw onthe side with 2 screws. Place the red wire around the third screw. Now go to the other switch and the neutral wire or white goes on the bottom of the 3 way switch side with 2 screws. The the balck wire on the same side top screw and the red wire on the opposite side top screw. The red and black wires are called travellers. I suggest you print a copy of a wiring diagram from google. Otherwise there should be a diagram on the box you bought the switch in...unless it is an reused switch or like most of us you threw away the box. Good luck...God bless. Capt. Hannu

Hannu Lindholm
March 2008