Properly driving a tri-rebel?

[cannibal869]

Hi everyone, I have a question - this might sound a little...well... late to the party, as I've already posted a RGB tri-rebel saber... but I'm wondering -

How would you wire up a tri-rebel so that you're properly or overdriving all 3 LEDs?

The way I have mine setup, I'm using a single 700 mA buckpuck to drive all 3 (via an 8 position switch). The switch is what made it so difficult - that and the fact that the specified max mA that the red could handle was 700mA. The blue and green could handle up to 1000 mA, but as my RGB was a sith saber, I planned on usually having the red on, and I didn't want to blow up the red.

Anyhow, back to the original question - if you're planning on running 2 of the 3 rebel LEDs at the same time all the time (i.e. not a color changing saber, but a single color... like say.... amber (red + green) or purple (red + blue) or cyan (blue + green)... how would you do it?

Use a 700 mA buckpuck for the red, and a 1000 mA buckpuck for the blue and/or green? Run the two buckpucks in parallel? Would you need 3 buckpucks?

What if you wanted to throw in a MR board for sound?

Maybe run one LED off of the MR board and the other one off of a separate switch? Power extender?

I feel like I'm trying to wrap my brain around something and the answer is just at the tip of my tongue, but I can't quite grasp it...maybe it's too late and I need to go to sleep now...
BTW, I'm also anxiously awaiting the MR + clash flash white tutorial, which might actually answer all of these questions anyway...

Still, any guidance or input would be greatly appreciated!
-C

[xl97]

Ive never done one..but what Ive seen of the red.. I believe people just put a regulator on the REd to not blow it..

as for your other questions,.. Im sure one of the more expeienced memebers will chime in.

[Goodman]

On one of my Tri-Rebels, I'm planning to drive two in series with a USv2.1, and the third on clash with a momentary, 1A buck, and separate batt pack.

On another of my Tri-Rebels, I'm planning to use a CF for the first two in series and power extender for the third.


Also, from my experience stacking buckpucks doesn't do what it says on paper. i.e., 700 buck plus 1A buck does NOT equal 1700ma buck. Where's Eandori...

...OR, you could just risk overdriving the red at 1000ma.


**EDIT** If you had the space, you could also consider a separate circuit for the red if you're going to be running it all the time as your primary. I know, I know...generally a silly, space-consuming suggestion, but this is coming from a guy who is working on stuffing three packs and two boards into the same hilt (different project). lol

[Jay Dee]

From what I've been told you can run the red @ 1000ma even though the specs say 700ma. You only need one puck just split the positive and negative into three different leads. Also for reference check out the for sale section of fx-sabers and find xwingbands thread on tri-rebels. He has a link to a pdf on the listing.Forgot about his spot incomsabers.com.

[LeMoel]

no xwing has stated that the red can safely run on 1 amp. and i just got my tri rebel and im going to run two of the leds off of a 1000 ma puck, and then the last one alone on 1000 ma

[cannibal869]

huh... cool thanks for the info guys!

Maybe I'll switch over my RGB to a 1000 mA buckpuck then...

Anyone else have other ideas?

[xwingband]

There's a ton of ways to do it. It depends on what you're running and can fit.

[Jay Dee]

I know the forward voltage is different but it seems like a nominal amount. Does it make that much of a difference? 3.15 to 2.9 would it just lessen the life of the led? Just curious about this if you could chime in x to clear this up I for one would be in your debt.

[Novastar]

Giving an LED a little bit more voltage than the listed "forward voltage" is not bad at all. In fact... it's likely that in order to get the "maximum brightness" out of any given LED... you need to give it more voltage than the listed fwd v.

This is NOT to be interpreted as: "Ok, it says fwd v = 3v, so I guess if I give it 5v, that should be even better". No.

But if fwd v = 3v... 3.15 is fine, 3.2 is fine too, and 3.3v or even 3.4v might be as well. As an example.

You can usually find specification sheets for LEDs where they list minimum, nominal, and maximum voltages. The fwd voltage is usually somewhat close to the "nominal" one.