We recently wired up some drawers of 3D glasses on charge so that when someone opens a drawer, ceiling lights come on.

Control was accomplished with a Crestron system controlling a Lutron panel, so the lights would only be activated if they were off, not if the house was at full lights.

The heart of this is of special note because it's so dead simple: If there's something closer than about 2" to it, the two output wires have no voltage on them. If there's something more than about 6" away, the output wires have the input voltage on them. Input voltage can be between 12 volts and 24 volts.
Here's what it looks like. The tube is about 1/2" in diameter:


The bracket can be removed for mounting these in a 9/16" hole. (Their data says 13 mm, which is too small, AND it says 14 mm somewhere else.)

They work between 2" and 6" because the actual switching distance depends on how reflective the target is. Black paper, it switched at 2." My hand, it switched at about 4." White paper or a mirror, it switched at about 6."

These are intended by Wessel LED, who imports them, to directly drive strings of LEDs, and they can output up to 30 watts. Their information is horribly non-technical, so I can't tell you if that's 30 watts at 12 volts but less at 24. Also, the devices have connectors on them that work with Wessel parts so the non-technical person can just string things together, but which Digikey could only come close to identifying. Wessel has no idea what the connectors are! (Maybe if a half dozen of you emailed them saying you want to use this product but you need the specs on matching connectors....)

There's only one caveat to using them: they don't switch the hot, they switch the ground. We put four of them together so opening any one drawer would turn on the lights. Since it's natural for us to connect all grounds together, I did that and found that it would not switch off. Input and output grounds cannot be connected to one another.

Anyway, this was a nice find. Enjoy.

Wessel LED is in Florida.

Nice. Does it have its own wall wart with selectable voltage (12v or 24v)?

Ernie, please account for the technically stupid person in the room. 'splain it

goldenz, this is from the world of DIY, but it's in a very strange niche: design and install LED lighting using pieces that just plug and play. The connectors they use only allow you to connect things one way and you wire it up power supply to proximity sensor to LED light string.

Then they throw in a technical spec, that it can work up to 24 volts, when, as far as I've looked, all their stuff is 12 volt. I was really only interested in the sensor, so maybe they have a line of 12 volt stuff and a line of 24 volt stuff.

Julie,
this set of products allows you to install LED cabinet lighting without having to turn a screwdriver (except for mounting the sensor) or install a connector.

Let's say you have a kitchen cabinet you want to light. You install the sensor, say, two inches inside the cabinet on the side away from the hinge, and you face the sensor forward. You plug one end of the sensor into a power supply and the other end into several pieces of LED light strip, all of which use the same connectors. Plug in the supply. Mount the LED strip where it will light up the area you'd like to illuminate.

When you open the cabinet door, the LEDs come on. When you close the door, the LEDs go off. The only construction details you have to implement are these:
*make holes to run the wire from the power supply into the cabinet
*mount the sensor, either using two screws that they include or slipping it into a hole you've drilled; cabinet construction determines that
*connect the sensor output to an LED strip and mount the strip where you want it.

So, okay, those are some mechanical details. But there's no danger when wiring it up as it's all low voltage. There's no messing with terminal strips or crimp connectors or the like, as the product comes with a single consistent set of connectors.

They did not envision that you'd be able (or even want) to have all the lights in several adjacent cabinets light up whenever any one of the doors is opened. That was my idea and challenge to implement. I worked out how to connect several of these to make that happen.

What I love about it is that, unlike a magnetic switch or mechanical switch, you don't have to have two surfaces and two parts that have to be mounted just so in relation to one another. Put it less than two inches from a moving part of the cabinet, it turns off. Move that part of the cabinet more than six inches away, it's on. With some experience you can position things more precisely than that, but you don't have to.

Got it, Ernie. Thanks!

schwa.

Would be fun for Halloween stuff too.