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lamp switches #58332
11/05/05 10:59 PM
11/05/05 10:59 PM
ds247  Offline OP
Joined: May 2003
Posts: 18
Just curious but does anyone know why many incandescent table lamp switches click twice rather than once to turn on and off?

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Re: lamp switches #58333
11/05/05 11:28 PM
11/05/05 11:28 PM
SvenNYC  Offline
Joined: Aug 2002
Posts: 1,691
New York City
ARe you thinking of three-way bulb sockets perhaps?

There are four positions: low, medium, high and off.

Of course this only works with the proper three-way bulb.

If you insert a standard bulb you will have to turn the key from its off position to the first "low" position" for which there is no contact.

The next stop would be medium and you'd get light.

The next stop is high and the bulb is still on (since medium and high use the same higher wattage filament in a three way bulb).

After that you turn the bulb off.

My guess is you're using the wrong bulb in your lamp.

Re: lamp switches #58334
11/06/05 09:47 AM
11/06/05 09:47 AM
DougW  Offline
Joined: Jun 2003
Posts: 1,143
North Chicago, IL
+1 for the three-way socket.

Re: lamp switches #58335
11/06/05 10:12 AM
11/06/05 10:12 AM
ComputerWizKid  Offline
Joined: Sep 2003
Posts: 119
Connecticut, USA
Is there any danger (as long as you don't go over the rated wattege posted on the socket Usually 150W) of using a regular bulb or Compact Floruscent in a 3 way socket?

Theres always enough room in the junction box.You just need a bigger hammer
Re: lamp switches #58336
11/06/05 10:52 AM
11/06/05 10:52 AM
Sixer  Offline
Joined: Aug 2005
Posts: 265
There should be no danger of putting a normal compact fluorescent in a tri-light socket...but they do make CFL's specifically for tri-lights and dimmers. I've got a normal CFL in my tri-light and it's been there for years and hasn't given me any problems.

A regular tri-light bulb has 2 filaments, on low one filament is on, medium other filament is on, and on high both filaments are on. If you look in the socket you will see an extra "pin" between the center point of the socket and the threads that the lamp screws in to...this pin supplies power to the 2nd filament.

This link has some good info on CFL's:


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Re: lamp switches #58337
11/06/05 04:56 PM
11/06/05 04:56 PM
Texas_Ranger  Offline
Joined: Dec 2001
Posts: 2,441
Vienna, Austria
Funny - I just stumbled across such a "double click socket" in the middle of Europe! A friend of mine has an imported US floor lamp and mentioned the weird switch today... just ditched everything but the shade today though (the socket had a bad internal short arcing to the bottom part of the bulb screw shell (next to the black stuff that separates center and shell)... and since the thread on the lamp is US it prove impossible to replace the shot socket with a European one which has a metric thread...

Re: lamp switches #58338
11/07/05 01:10 PM
11/07/05 01:10 PM
SvenNYC  Offline
Joined: Aug 2002
Posts: 1,691
New York City
Ragnar, You could have given me a holler. I have plenty of spares knocking about. Both standard American lampholders and three-way (hi/lo) ones.


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