Adafruit Tower Light - Red Yellow Green Alert Light with Buzzer - 12VDC [ADA2993]
THE REACTOR'S MELTING DOWN! GRAB THE FUEL CORE, JENNA, AND EVACUATE THE COMMAND CENTER! With this flexible Red-Yellow-Green Alert Light you can monitor the status of a project, machine, or even if the bathroom is occupied!
We got some really nice tower lights here, first up they come in slimming Adafruit black, they're easy to attach with mounting holes, and you can rotate the light mount so it can be horizontal, vertical or any angle in between (180 rotation).
This is the tri-color version but we also have a smaller Red-only Alert Light in the store if you want a smaller, simpler alert light
Alert tower lights are really easy to use. The brown wire is the common +12V power line, then the other wires are connected to ground to activate each of the three LED lights: red wire for red light, yellow wire for yellow light and, you guessed it, green wire for green light. The final orange wire is what controls the buzzer which will sound continuously when the wire is grounded. We did notice that you can't have both the yellow and red lamps on at once, and in general its best to only have one lamp lit at a time for max brightness. The buzzer can be turned on whenever, it does not seem to be affected by the lights.
You will need a 12VDC power supply to get it going, the one that we carry will do well for fixed installations. If you are using this with a 3V or 5V microcontroller or computer, use 4 x NPN transistors or N-channel mosfets to sink current from each wire. Our guide on analog LED strips is pretty much the same wiring you need, except its only about 50mA per segment. If you desperately need something that can run off of 5V you might consider wiring up your own white LEDs instead of using the LEDs that come with it.
Note: Shipping weight reflects UPS' new dimensional weight regulations.