"BOB" wrote in message
...
I know there are motion sensors which detect movement and can turn on
a light fixture. What I was wondering is there a way to do this inside
a house? I would need one that would detect a person walking _into_
the room so the light would cut on several feet before a person enters
the room.

Can be done, but if you want it to happen -before- someone gets into the
room, it's a little more tricky. Problem is, motion sensors don't "see" the
target well when the target's motion is directly toward or away from the
detector. Since they detect motion by way of a change in heat, and you want
to do this indoors which is close to body temp (as opposed to outside), you
may well be within arm's length of the sensor before it sees you.

It can see you in an instant from 20 feet or more if you move _across_ it's
field of view however. You can adjust the sensitivity, but sometimes the
thing will be triggering the lights so often that a plain ol' switch would
be better.

Most flourescent lights won't work with these switches either.