Servo Controlled light switch

I'd think that would be a typical function of home automation systems,
but I don't know for sure since I don't do that.

If I were into home automation, I might solve the problem by using the
physical wall switch as an input to the automation controller rather
than to directly make or break the light circuit itself.  The
automation controller, not the physical switch, would activate the
light (or whatever else I choose) according to rules programmed into it
which could include a variety of actions on the wall switch in
combination with other inputs such as timers, sensors, etc.

JM

Your recommendation sounds like a good option.
The reason I was looking at the automation controlling the switch, and
not the switch imputing to the system is that I would like to "The
House" operational, with or without the computer. I would hate to have
a PC failure, and my house crashes as a result.

Mike

John Mianowski wrote:

Well if that's the only reason, you needn't worry.  If you replace your
light switch with (say) an X10 switch module, then it continues to work
without any other computers online.  The switch module simply sends a
command onto the house wiring, and the lamp module (or whatever)
responds by turning itself on or off.  Your computer can ALSO send
commands to turn it on or off, e.g. on a schedule you define or when you
run some "leaving the house" program.  But the computer's just another
input (and output, if you wish) to the system; it's not a critical
component.

Note that switches like these don't have a physical indicator of the
current state.  Usually they're just a long button, and you push it on
one side for "on" and push it on the other end for "off."  I like your
idea of a physical switch that actually moves to indicate state, but
it's probably not necessary -- most of us have 2-way (or 3-way) switches
in our house, in which case the physical position of one switch doesn't
reflect the state of whatever it controls anyway.

(Though it'd be cool if it did -- imagine flipping one switch, and the
other switch on the same circuit moves accordingly!  That'd be nifty,
but doesn't seem high on the list of world's problems to solve.)

Best,
- Joe

My wife (and myself to some extent) are compulsive about switch positions
for 3-way switches.   We like them configured so when they are all down,
the light is off, and we only want one light switch up when the light is on
(we have one string of 3-way and 4-way switches in the house that has 4
switches in it).  So we tend to do things so we always turn the light off,
with the same switch we turned it on with, so that the switches always end
up in the all down position when the light is off.

For people like us, switches that moved on their own at all locations so we
wouldn't have to run around and "fix" the switches all the time would be
cool!

I think just having an indicator light showing the status of the circuit
(on or off) and using momentary switches might be just as good (but not as
fun).

--
Curt Welch                                            http://CurtWelch.Com/
curt@kcwc.com                                        http://NewsReader.Com/

   Although such things as remotely moveable toggle switches do exist,
what you probably want for home automation is more like this:

    http://www.smarthome.com/2271ai.html

There are some high-end audio mixing boards where all the controls
are motor-driven, so you can save and restore settings.  But those
devices are expensive, unreliable, and won't fit in a standard
switch electrical box.

If you want to see some switches that can physically be moved by
remote control, see

     http://www.flamecorp.com/pdf_files/ettoggle_7.pdf

These are MIL-spec aerospace qualified toggle switches used
for things like "Engage Autopilot" in aircraft.  They're expensive.

                    John Nagle

mike wrote:

---snip----

You might want to eBay for X-10 controllers and remote switches. Should be
at bargain prices today.

Another solution would be to wire your computer controlled relay as
part of a 3-way switch. The only disadvantage of this, is that you
would then need a relay that is in parallel with the light to let you
know that the light is actually on.

The other way to know if the light is on or off, is to put an inductor
around one of the wires leading to the light. When the inductor gets
some activity, you know that the light is on.

mike wrote:

    Does it have to be physical?  There are light switches (rocker style,
illuminated) that light up when their load is off (so you can find them
in the dark), and go dark when their load is on.  Putting one of these
in a three-way seutp with an X10 module might be one alternative.