2 or 3 X LML Trying to learn more about amps and voltage.....?

How do I determine how many amps I can push to multiple XMLs? I'm thinking 2-3 XMLs and I have the ability to use 1-2 IMR cells in this light. I will be heatsinking with copper. The driver choice will be between a buck thats adjustable up to 6.6 amps or an AMC 7135 with added chips. Will a driver push multiple leds at its rated amps or do you divide the amps by the number of leds.

SteveoMiami said:

Will a driver push multiple leds at its rated amps or do you divide the amps by the number of leds.

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That depends on the way your emitters are being connected.
If in parallel, you will have a constant voltage but split current.
If in series, you will have a constant current but split voltage.

For example, 1 x cell (3.7V) & a 3000mA driver
Parallel:
Voltage to each emitter - 3.7V
Current to each emitter - 3000mA / number of emitter

Series:
Voltage to each emitter - 3.7V / number of emitter
Current to each emitter - 3000mA

And btw, if you are planning to go by stacking of the amc chips, then the 2 x IMR CELLS is no longer an option.
From what i remember, those drivers have a max voltage of 6v only.
2 IMR cells might kill the driver.

So in order to drive 3 xmls at lets say 4 amps what would I have to have? I can see that the AMC chips wont work but the buck driver I'm looking at will. With this driver would I be able to use 2 batteries or would it need more? http://www.taskled.com/h6flex.shtml

SteveoMiami said:

So in order to drive 3 xmls at lets say 4 amps what would I have to have? I can see that the AMC chips wont work but the buck driver I'm looking at will. With this driver would I be able to use 2 batteries or would it need more? http://www.taskled.com/h6flex.shtml

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Yeah, that driver could work but with 2 cells or more. Since min input is 7v.
The AMC chip setup could work but only with a single cell setup.

JonK

Sent from my Awesome phone from somewhere in the mountains

So the VF of the XMLs at 5 amps would be over 3 volts each. Wouldnt I require the 3 volts X 3 leds = 9 volts minimum in order to supply the required 5 amps?

If running in series, yes.
You will need 9v in order to supply 3v to 3 emitters.

JonK

Sent from my Awesome phone from somewhere in the mountains

It's important to note that your LEDs in parallel may run into trouble. Suppose that your three have one with a very low forward voltage, and the others typical. The low-forward-voltage LED will be rather overdriven.

Looks like they will be in series with 3 batteries

Both ways of connecting the emitters will have their own problems.
When in series, if 1 emitter is damaged then the whole circuit won't work anymore.

JonK

Sent from my Awesome phone from somewhere in the mountains

What matters in this light is that it puts out the most lumans possible in the smallest package possible. From my perspective (relative noobie) series is the way to go.

Make sure you use quality li-ions. Grouping them can lead to exciting results if one cell, weaker than the others, reaches 0v and reverse charges.

My battery choices are 3 IMRs or I 3 panasonice cgr1860s. All of which are brand new. I know putting 3 battieres in series triples my voltage. What does it do to my amperage. I'm asking because I think the panasonics I have are only good for like 2.5-3 amps.

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They will be wired in series and the high mode will be at 5 amps. The High mode will be used more like a turbo mode or a burst mode. Just for max brightness. Any extended use of this particular light will be in the lower modes. My other option is to use a single MTG2 led insead of the 3 X XML2, I have a couple MTG2s in the mail from Cutter already and have yet to order the XMLs. What is your opinion on that? I'm pretty new to this but I have several projects going on at once and I like to jump right into the fire I guess. This is my crazy project I guess you could say.

SteveoMiami said:

What matters in this light is that it puts out the most lumans possible in the smallest package possible. From my perspective (relative noobie) series is the way to go.

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Then just do it via direct drive....and a simple on/off UI.

I thought about it but I would like to also have a little bit of usability out of it, is that a word.....

SteveoMiami said:

I thought about it but I would like to also have a little bit of usability out of it, is that a word.....

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I think its a word. I also think it means that "As much as possible" does not mean what you think it means.

I obviously dont know what I want to do......Hopefully I'll have it figured out by the time my reflectors and hacksaw get here... I'm ready to start hacking on this copper rod I have maybe it will end up being a 3 X XML2 Mule I would have a lot more room for the copper and it would survive longer on those 5 amps