not robotics, but help would be appreciated

[impulse3D]

Originally Posted by LauraN

*drags out physics*

... power=I²R. So the amount of power you'd be drawing would decrease because you've decreased the resitance, but then increase proportionally the the square of the corresponding increase in current... I think I've totally confused myself...

Actually, all the stuff about increasing yet decreasing could be explained a lot clearer and in an easy-to-understand way.

Given V=IR and P=I²R; we know that IR is always constant because your voltage will remain constant, so IR can equal K. Essentially P=I(IR) [I just rearranged the variables under the commutative property], so P=KI. This shows that you need not worry about decreasing resistance, compensating in amperage, and increasing due to squaring; rather, there's just a simple linear relationship.

You could even graph it if you wanted to, whereas P=y, K=m, and I=x under the function y=mx+b! (b=0, obviously, because when your voltage is zero your IR HAS to be zero as well)

[KenWittlief]

there is another way you can do this without having to run romex (power) wires

there is a low voltage control system for 120VAC applications - bascially you put this small relay module inside the light fixture, and it only takes a pulse of 12VAC to switch it on or off

so you can put the control switches anywhere in your house, and have as many as you want controlling one light or outlet -and you only need to run doorbell wire for the controls intsead of 3 conductor 14 gauge romex.

Its pretty neat - if you wire your whole house this way (when its built preferrably) you can also have a master control box, like in your bedroom, and if you want to hold the 'on' button down and sweep the selector switch - and turn all the lights on in your house in about a second

or turn them all off :^)

[Astronouth7303]

What about the 'network' setup that uses regular wiring? it sends a bit when the AC current hits zero (sine-wave thing). So in the USA, that's 60 bps. I can't remember what it's called!

(and for anyone using dots to draw, try the [code] tag)

[seanwitte]

You could also use X-10. There are lamp and appliance modules that each have switches to assign a unique House and Item number. You just plug it into a wall outlet and then plug the lamp into it. They have various RF remotes that you can program to actuate the different modules. It requires no wiring at all, but houses on the same transformer will share signals.

The remotes work with a receiver that plugs into a wall outlet to send the X-10 commands to the units over the home wiring. There is also a computer module so you can send X-10 commands from a PC. The basic stamp also has X-10 capability built in. They also have some nifty motion sensors so you could turn the lights on when you start walking down the stairs.

[Bill Beatty]

Operating a light from two or more switches is very common situation and has been done in house wiring for many, many years. The proper way to do it without going to a low voltage system is as GeneF describes.

From you comments, I strongly advise you hire or enlist the aid of an electrician who is familiar with the wiring codes in your area.

Mr. Bill

[KenWittlief]

good advice - if you do make a mistake and your house burns down, and they determine inproper do-it-yourself wireing was the cause

then your insurance company will pay you $0.00 for the loss of your home and everything in it.

[Astronouth7303]

That's what I'm talking about! The X-10! thanx!

[Astronouth7303]

Originally Posted by Bill Beatty

Operating a light from two or more switches is very common situation and has been done in house wiring for many, many years. The proper way to do it without going to a low voltage system is as GeneF describes.
...

Yes. Go to Home Depot and look for double light switches. There are also triples, which if you put in between, allows for 3 or more switches.

[Al Skierkiewicz]

Well,
The best suggestion so far is the X-10 system. If you look around (I think Radio shack still carries the line.) They have a remote that will turn the lights on from anywhere you are near the house. You need the base station and a controlled light switch, about $30 or so. I know that Home Depot had a remote control switch they were selling a year or so ago made for turning lights on the outside of the house or garage on/off. I believe the selling price was $18.

As to the Ohm's Law questions...For the most part it is not applicable in this situation. Remember that power is the quantity consumed in the light. Say it is a 100 W light bulb, than the current is less than an amp. (Remember we are talking 120 volts not 12 volts) The incidental current changes supplied by multiple paths are going to be negligible with such a low current. The change of series resistance will not be enough to change the light output where you would notice it.

Safety, safety, safety always. Adding switches is not a big deal in the scheme of things, but when you start talking about multiple paths and the possibility of a switch near the bulkhead (possible wet location) then you have reached the point where a pro should be consulted.

[pryoplasm]

Originally Posted by Al Skierkiewicz

Well,
The best suggestion so far is the X-10 system. If you look around (I think Radio shack still carries the line.) They have a remote that will turn the lights on from anywhere you are near the house. You need the base station and a controlled light switch, about $30 or so. I know that Home Depot had a remote control switch they were selling a year or so ago made for turning lights on the outside of the house or garage on/off. I believe the selling price was $18.

As to the Ohm's Law questions...For the most part it is not applicable in this situation. Remember that power is the quantity consumed in the light. Say it is a 100 W light bulb, than the current is less than an amp. (Remember we are talking 120 volts not 12 volts) The incidental current changes supplied by multiple paths are going to be negligible with such a low current. The change of series resistance will not be enough to change the light output where you would notice it.

Safety, safety, safety always. Adding switches is not a big deal in the scheme of things, but when you start talking about multiple paths and the possibility of a switch near the bulkhead (possible wet location) then you have reached the point where a pro should be consulted.

no problem...as for people mentioning double and triple switches, that doesnt help me....and would the X-10 thing work since its not an appliance that plugs into the wall, but something that has been hardwired into the house?

i mean, i would have to rewire it if using the X-10 thing....
right?

[Pierson]

There are many ways you can use X-10. You can get the Light bulb attachment, this screws in between the fixture and the lightbulb. You can get switches that either wire into the electrical system, or just plug into any outlet.

I have never used these people, but you can get X-10 stuff here: http://www.smarthome.com/

[Al Skierkiewicz]

Originally Posted by pryoplasm

and would the X-10 thing work since its not an appliance that plugs into the wall, but something that has been hardwired into the house?

i mean, i would have to rewire it if using the X-10 thing....
right?

As Peciv stated above the X-10 system is available from Smart Home. I have found them to be higher priced than some X-10 suppliers. From Smarthome though, order either a 2005 for $16.99 or a 2005CM for $17.99, add a 4003 for $25.99 and you get a light that you can turn on with a key fob remote. If you feel you can replace the wall switch( i.e. remove the current one and replace it with a new wall switch and plate.) then go for any of the wall switches instead of the 2005. The light switch needs to be ON all the time to use the remote with the 2005 (CM) but will work just fine with the wall switch. The wall switch products work just like normal wall switches when not used with the remote. You can also add one of the remote products to automatically turn off the light at say midnight, to insure you are conserving energy. The normal X-10 system broadcasts codes through the house wiring that can control up to 256 different devices. I have used X-10 modules to turn on/off lights throughout the house and even used them on Christmas lights outside. They have been around for many years and if you build up a system, you can add a computer interface which will turn lights on and off all over your house and property.