Wiring your LED tube indicator (the illegal way)

[RyanN]

Originally Posted by Mr. Lim

A lot of our team has come down with a nasty cold/flu bug lately, but one of the benefits of this has been the strange "snot box" that the team collectively produced. It also happens to signal to our feeder what type of tube we would like him to deliver to our robot.

http://www.chiefdelphi.com/media/photos/36292

The snot box is wired for 12V, and each of the three indicators uses about 60mA of current. While trying to figure out how to wire the thing, we broached a few options:

1) 2 Spikes: 1 - 12V supply from the PDB via 20A breaker, 2 - relay outputs from the DSC

2) Custom circuit: 1 - 12V supply from the PDB via 20A breaker, 3 - digital outputs from the DSC

3) Solenoid Breakout (illegal): 3 - solenoid outputs from a 12V powered solenoid breakout

I'm pretty sure #3 is illegal, but I would love to be proven otherwise, because I think it's the most elegant option of the 3 above. Fundamentally the "Solenoid Breakout" is a DC Sourcing Module rated for 750mA per channel - it's not specifically made to power solenoids. The limitation is that it can't source a large amount of current.

But it does have the juice to source 60mA worth of LEDs, right?

If it does, wouldn't it be the nicest way to power the "snotbox?"

You can get away with one Spike if you want. Wire the positive side of the LED's to M+ and M-. M+ would control one LED set, M- would control another LED set.