LED wiring and switch harness questions

[skorpien]

Hello,

I was hoping to get some advice with LED wiring and using a Lamptron switch. I have one of these Bitspower X-Station LED Power Hubs (with green LEDs instead). I'm planning on modding 12 fans to have LEDs (4 each) and if I were to plug each individual LED into the hub, I'd run out of terminals fast. The hub has 40 terminals, but only 20 are 3.3V for LEDs without a resistor.

What I was wondering is if it would be okay for me to wire 4 LEDs in parallel to a single 3.3V terminal. This would cut the terminals needed to 12 rather than 48, but I'm worried that doing so would be bad for either the LEDs or the hub itself.

I'm also thinking of using some 2.0V LEDs (orange) and was wondering if it's absolutely necessary to use a resistor with these when connected to the 3.3V terminals?

Lastly, I would like to use a latching Delrin anti-vandal switch (Lamptron) to control the hub, turning it on and off at will. The hub uses a 4-pin molex from the PSU and I was wondering how I would go about hooking it up to a switch. Is it okay for me to cut the 12V line going into the hub and connect it to the switch? With fans and other peripherals that use either 12V or 5V it's pretty easy, but I'm at a loss as to how to do this with the hub.

Thanks in advance for any help you can offer.

[Hooded]

I would think that running 4 LED's in parallel would be fine per 3.3v connection.
The 2v LED's will require a resistor or two in a series hook up. Other wise they will fry.
For the switch I would use the last molex connector on a parallel circuit and tap into the 12v ground to hook up the switch.

[gdesmo]

Actually 4 x 2 volt Led's in a parallel still has the full 3.3 volts across it and will blow right away ! What you need to do is put it in a series-parallel which would drop the applied voltage across each Led to 1.65 volts, will dim slightly but easiest way to do it. Will post again with a diagram.

[gdesmo]

Don't forget the longer lead on the light is the positive side of the diode.

[skorpien]

Thank you both for the replies Much appreciated!

gdesmo, I'm planning on using a resistor for any orange LEDs. I ordered a bunch from eBay after using an online LED circuit builder (handy things, those). I definitely don't want any of my LEDs frying...

Great to hear about the switch, Hooded! I've tested it out like you suggested (rudimentary circuit, nothing permanent), and both the parallel 3.3V LEDs and the switch worked perfectly.

All that's left is to finish drilling the holes in the fans so that I can wire them up and solder everything properly! Waiting on my DazMode order of Scythe GTs to come in either today or tomorrow

Much appreciated, thanks again!