DIY Dusk to Dawn Porch light

September 7, 2005 8:18 AM

How to convert a porch light to be light-sensitive?

I have a light fixture on the ceiling of my porch. The pre-packaged light-sensitive ("dusk to dawn" -- turning on at dusk and off at dawn automatically) lights I've seen all need mounting on the side of the wall (where I don't currently have wiring.) What I'd like to do, if possible, is just get a light-sensitive panel, mount it on a wall, trail wires from it to something I can screw into the light socket, and into which the bulb screws. But I don't know if those things exist such that they'd work together in that way, or what I'd call 'em so I could look them up. Anyone have any pointers?

posted by Zed_Lopez to Home & Garden (10 answers total)

There are add-on devices for wall-mounted floods and they're pretty simple; you connect them to the hot and neutral wires and connect the light's hot wire to the (usually red) output from the sensor. They're fairly cheap but usually in an enclosure meant to go into the quarter-sized hole in a gang box.

It's certainly something you could jury-rig up. Try not to shock yourself or burn down your home.
posted by phearlez at 8:23 AM on September 7, 2005

Best answer: It's not specifically the solution you're looking for, but there are light sensors that will screw into a regular light socket. You put the sensor in the socket, and then screw the light bulb into that. Since it extends the protrusion of the bulb, this won't work for every light fixture.
posted by LionIndex at 8:30 AM on September 7, 2005

I hope this doesn't sound unhelpful, but go to your local hardware store and tell them what you're trying to do. Depending on the selection, they'll either tell you to bust apart a wall-mounted set or they'll have the light sensor. If they don't have a stand alone, you may want to go to Radioshack and pick one up, depending on how you feel about buying a set and busting it apart.
But it's, like, about the easiest thing to do if you have access to the wires (before the fixture), which it sounds like you do. The light sensor will have wires soddered to it, you just twist 'em and use a wire nut to secure them, and make sure to both weatherproof the wiring (either by moving it back inside the roof of where you're working or by taping over it), and mount the sensor so it faces out with the sensing side pointed perpendicular to the ground (that's one reason why these are usually wall lights: that's the orientation you want for the light sensor if you want it to be the best at sensing when to turn on and off).
Seriously, aside from getting the parts, this shouldn't take more than 20 minutes of your time.
posted by klangklangston at 8:39 AM on September 7, 2005

You could go with an X-10 controller which would tackle multiple lights as well. You need to replace the light switch with an X-10 capable one to work with this controller, but that is a simple swap out (with the power shut off of course).
posted by caddis at 8:45 AM on September 7, 2005

There are also bulbs with the photocell built in, but I can only find UK versions.
posted by caddis at 8:48 AM on September 7, 2005

Photocontrols.
posted by jellicle at 9:32 AM on September 7, 2005

caddis, I did find one US vendor for bulbs with built in photocell.

Great question. I've been trying to solve this same issue for my partner. The thingie that goes between the lightbulb and the socket seems to be the item that caused a giant spike in her electricity bill.
posted by QIbHom at 9:39 AM on September 7, 2005

Maybe the technology has gotten better, but a few years ago I bought a bulb with the photocell built in for use on my back porch, and what would happen is when darkness came, the light would come on. Then, light from the bulb would hit the photocell and cause the light to go off. The end result was an endlessly flickering porchlight that I eventually ended up throwing away. YMMV.
posted by spilon at 10:13 AM on September 7, 2005

While not photocell, I've gotten pretty good mileage from a timer switch replacement. For about $30 they drop in to a normal switch location and provide fairly complex scheduling.

Two downsides: one is that it needs reprogramming if the power fails and the other is that it "pings" the lightbulb fairly regularly to see if its still alive. Doesn't create problems for most filament bulbs but was kind of wacky with a compact florescent I had in there...
posted by Ogre Lawless at 11:35 AM on September 7, 2005

Got the lightbulb I linked to above, and it doesn't have the flicker issue spilon reported. Bit brighter than I'd like, though.
posted by QIbHom at 3:27 PM on September 12, 2005