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Consistent-position two way switch

Inspitred by Ian Tindale's post in "OCD status check for OCD sufferers"
  [vote for,

Many homes have two-way light switches, particualrly in stairwells.

These switches have a shortcoming; the "on" and "off" positions reverse when the partner switch is operated.

This can lead to a wall plate where both switches are in the "off" position, yet one is up, the other down.

There are two solutions

1. The switches are replaced by non-latching pushbuttons. Each push changes the state of a flip-flop which controls a solid-state relay. Push on, push off, all switches always correctly aligned.

2. Rocker switches with a small solenoid and some control logic, linking each pair of switches. When the partner switch is toggled, after a short delay, both switches snap into the "correct" position consistent with the status of the light.

8th of 7, Aug 07 2009


       Actually, in a two-way switch system, it is dependent entirely upon which way the switches are installed. Either 'on' is consistently both toggles in the same configuration, or consistently opposite eachother. There's no way to effect the logic unless you flip the switchbox over.   

       Both of these seem sortof baked, by-the-way.
RayfordSteele, Aug 07 2009

       I must admit, I have gone back and forth in houses to flip things around in an effort to make both the switches "correct".   

       Push button switches for on and off are no good, however. I have an X10 lightswitch which is a button, and i find that when I'm entering a room where the lights were left on, I turn them off by habit, and when leaving a dark room, turn them on.   

       A toggle is nice because on stays on and so forth.
ericscottf, Aug 07 2009

       a real buggar if you want to change lightbulbs and *hate* it when the new bulb lights up in your hand.
po, Aug 07 2009

       Use double-throw momentaries at both locations. For each switch, "up" will energize a latching relay, "down" will turn it off. The switch will always return to center, and always moves in the same direction for the same action. (So pushing it down when the lights are off doesn't do anything.)
lurch, Aug 07 2009

       Just buy a feckin candle.
MaxwellBuchanan, Aug 07 2009

       //(So pushing it down when the lights are off doesn't do anything.)//   

       Except in the UK, where it's necessary to invert the circuitry so "up" is Off, and "down" is On.
csea, Aug 07 2009

       //in the UK.... "up" is Off, and "down" is On//   

       Not so. "Down" is On and "up" is Off.
MaxwellBuchanan, Aug 07 2009

       //in the UK.... "up" is Off, and "down" is On//
Just be sure to mount the switch cross-wise.
lurch, Aug 08 2009

       // the depressed bit or the bit left out //   

       Ah, the eternal dilemma of choosing between Unipolar Disorder and Paranoia resulting in Social Exclusion....
8th of 7, Aug 08 2009

       Even if you flip one (or both) of the switches over, you still have a situation where the fixture could be either on or off with any pair of configurations.
Jscotty, Aug 09 2009

       This must be the slow class ....   

       At the bottom of the stairwell is a 2-gang light switch. One switch operates the porch light, the other the stairwell light. Up is off, down is on.   

       When the porch light is on, the switch is down, when it is off, up.   

       A person enters the house. The porch light is on. The switch is down. They turn off the porch light and turn on the stairwell light. The porch switch is now up and the stairwell switch is down. The upstairs switch moves DOWN, indicating ON.   

       The person goes upstairs, turns on a bedroom light and switches the stairwell light off by moving the switch UP. The downstairs switch also moves UP (= OFF).   

       The light remains OFF.   

       Please, try to understand before you die.
8th of 7, Aug 09 2009

       in an open stairwell just use one of those pullstring fixtures.
FlyingToaster, Aug 09 2009

       Good idea, [FT], why don't you make a noose and hang yourself from one ?
8th of 7, Aug 09 2009

       I tried; got cut down by somebody that wanted to turn the light off and couldn't lift me.
FlyingToaster, Aug 09 2009

       Damn. We'd have got away with it too, if it wasn't for those pesky kids ......
8th of 7, Aug 09 2009

       I am just finishing off commissioning a very upmarket apartment that has a lighting control system.
A Pair of pushbuttons are set (left is on/Dim up, right is Off/Dim down). Each active status can be set on the switch via a feedback object. We have two of these, one at the top and one at the bottom of the stairwell. Because the system is on a network bus you can use the same button for the same function and can synch the active status on the pushbutton LEDs to either tell you which one is active or else indicate which button you should push to change the light status.
Very expensive but very functional.
gnomethang, Aug 11 2009

       ZOMG I LUV U!!!!
twitch, Aug 11 2009


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