As a newbie to the world of home automation, I have what may be a basic
question.
In back of my home I have three dual floodlights (with two 75w lamps in
each) which are switched on and off at a switch inside the house.
Is it possible to add a motion sensor to the system so that these floodlights would become "security lights". If so, what would I need to
purchase and could I, with my minimal skills, do the installation myself? Would I replace the exsiting switch with something else?
You would need to purchase a 'motion sensor'.
the 'simple way' is to purchase one for each fixture.
These are a simple, self-contained gizmo that mounts to the junction box that the lights mount to, and connects to the wiring inside the box.
This is _probably_ something you can handle yourself, *if* the design of the light fixtures is a 'friendly' one.
You would *not* need to change the existing switch, _but_ the lights would come on *only* when (a) the wall switch inside is 'on', *AND* something triggers the motion detector. And only those lights whose sensor was tripped would come on.1
To have the lights unconditionally go on when the switch is 'on', and to to individually turn on by motion detection when the switch is 'off', requires additional wiring between the switch and each fixture.
If you want _all_ the lights to come on when a single motion detector is tripped, then a 'replace the wall switch' approach may be indicated. put an X-10 (or similar) switch in place of the current one, and "somehow" hook up an (independent of the light fixtures) motion detector to generate an 'on' signal to that X-10 switch.
It's pretty easy to replace the fixture you have with a fixture that has a built-in motion detector-- they cost around $20 or $30. The more expensive ones tend to have a wider range (a wider angle of view to detect motion). You leave the switch on all the time. If you want to turn the lights on regardless of motion, most of them will allow you to do that by flipping the switch off then on again (then the lights stay on all night or until you flip it off and on a second time).
Be SURE SURE SURE to turn the power off (obviously) before you start taking things apart, and it's a good idea to replace the wire nuts (the colored plastic caps that hold the wires together) when you install the new fixture. Some fixtures come with the nuts, but if it doesn't, you can buy a box for a couple of dollars-- I'm pretty sure they're color-coded by size and the box should tell you which ones to use based on how many wires of what size.
If you have other X-10 remote-control stuff in the house, X-10 sells a motion-detector fixture for $50 (but if you're in no hurry their stuff is often on sale; a couple of weeks ago I got two for $50) which will allow you to turn the lights on and off from anywhere in the house, in addition to the motion-detector feature. The one drawback is that the X-10 motion detector's range of view is only 110 degrees, rather narrow.
Shaun Eli
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