THE REACTOR'S MELTING DOWN! GRAB THE FUEL CORE, JENNA, AND EVACUATE THE COMMAND CENTER! With this Rotating LED Warning Light with Adjustable Volume Buzzer Alarm, you can monitor and easily alert humanoids as to the status of a project, machine, or even if the bathroom is occupied!
This alarm is very very simple - provide anywhere from 3V to 12V DC to the two power wires, and the LEDs inside start lighting up in a rotating manner. If the volume knob is turned up, you'll also get an incredibly-annoying buzzer sound as well.
If you want to turn this on only sometimes, you'll want to use a power transistor (like the venerable TIP120) or power FET (like this nice N-Channel MOSFET) to enable or disable power. Since it isn't inductive, you don't need a protection diode. We have an example guide on using transistors to power a high current item here.
If you want something with multiple colors, we got some really nice tower lights here.
