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How to wire a 3 terminal socket ( i believe they are called 2 way sockets Answered

I would like to put led mini lights inside of a liquor bottle lamp that i bought, my question is how can I connect this to a 3 terminal socket so i would be able to turn on just the mini light, or just the lamp bulb or both at the same time.


Jack A Lopez

10 months ago

They are called 3-way sockets, but it is like you say, a socket with 3 terminals, and it is made to connect to a light bulb, that also has 3 terminals, and 2 filaments.

I think 3-way refers to the number of permutations with at least 1 of the 2 filaments turned on. Technically it would would be 4-way, if we included the state with both filaments off.

way f1 f2
0 off off
1 on off
2 off on
3 on on

Getting back to the topic of shape of socket itself: it is a variation of the Edison screw style connector,


That same wikipedia article has this to say about the 3-way variant:

Three-way lamps have a d suffix to indicate double contacts, usually
E26d or E27d, or rarely E39d. The second contact is used for the
lower-wattage filament of the two inside the lamp. This extra contact is
a ring located around the main contact. Unlike bayonet sockets,
three-way and regular lamps are interchangeable, although the low
filament or low setting doesn’t work if mismatched.

Anyway, if you want to use the existing switch, I think the best way to do this would be to find, or build an adapter to convert a 3-way light bulb base, into the corresponding 3 wires. I call these: {N, L1, L2} where N is connected to the mains (N)eutral conductor, and L1 and L2 get connected (or not) to the (L)ine conductor, depending on the state of the switch.

Sometimes Line is called, "Hot", depending on who you ask.

Or another way would be to take apart the existing light switch, and add those two new wires L1 and L2 where they need to be. Although to do that, you kind of need to do some surgery on the insides of the light switch.

By the way, you will know if you possess the skills needed to do 3-way lamp switch surgery. It is like being in love. You'll just know. ;-P

Also you might be able to find a different switch, that has the same outputs, except in the form of wires, instead of a funny shaped socket.

For example, a switch made for a 3-speed, mains powered fan, is similar. Is rotary switch with like 4 positions, including off, and the logic is similar. It just switches L to like two or three different wires, that could be called L1, L2, L3, etc.

Actually, where I live, swamp coolers are popular, and a replacement switch made for one of these can usually be found cheaply, especially during the summer months. This switch has 6 different positions(arranged in a circle, 60 degrees apart), and outputs for three different AC loads, namely, a water pump, plus two different windings on the blower motor.

But you know, there is no reason why you could not wire up one of those to turn on mains powered LED light bulbs, or xmas, fairy light strings, or whatever.

I feel like I should point you towards some pictures of the swamp cooler switch wiring. Just the results of an image search, here:


BTW, the same trick, of using an image search, can be used to reveal pictures of the wiring of any kind of device that is common, and that people are writing about, e.g. 3-speed fan switch wiring , 3-way light bulb wiring, etc.


10 months ago

What you want may be hard to find (at least in the UK) - 3 way sockets don't exist, you use single sockets with 3 way switching.

HOWEVER - The wiring scheme shown below will allow you to turn on the small lights OR the big light OR Both using 2 switches.

As always, if your not proficient in wiring mains electricity get an electrician to do it for you - no point in killing anyone. Use this at your own risk.

Mains in.jpg