7.8’ish volts? With the LED’s in series, shouldn’t you have around 10v to turn them on?
do you use 3 or 4 cells in series to power that thing?
Using 2 x 26650, as I was under the understanding that should work. I was recommended this driver for this setup in a previous thread.
Driver spec says:
“Operating voltage:3-18V”
Should I be doing something different to get this to work. At this stage I’ve got myself completely confused with series and parallel in regard to what voltage will be sent to each led vs current.
the driver can’t put out enough voltage to run this setup in series unless you add another battery. If a third battery is not an option, then the bottom right emitter needs to be flipped back around and the jumpers need be put back on to make a parallel configuration. It then will work
I think this is no boost driver!
rebuilding to parallel should bring the light…
Assuming that the led’s are ok and all soldered joints have connection there is only one reason for it not to work, the star that is.
A short, double check that where you removed the jumpers has no solder left to bridge the gap, the top (in the pic) one looks like it is bridged.
Cheers David
I know I might get my hand into fire by replying but the current setup is nothing, neither parallel neither series because the jumpers are removed. Edit: I was looking at the OP image
Soldering the jumpers back will make the connection in parallel if you have not switched the position of the LEDs.
Or switching the polarity of the lower right LED without having jumpers soldered will make the configuration in series. Careful with the wire inputs where are soldered.
That driver claims that it is boosting right, then you need less input voltage than output voltage, very clearly, again if it is a boost driver.
"Automatically buck: single lithium or double-lithium can promote 3-4XML boost,"
This of course makes no sense. Buck is not boost, Boost is not buck simple as day an night. But still one could try to deduce that inputting 2 cells should makes the driver be able to run 3-4 LEDs in series.
I agree your emitters are properly installed now for a series setup but a couple of other things come to mind.
This would be easier if I could mark up your photo but I’m not sure how so here goes, all comments relative to your photo in post 48.
Confirm the jumper pads closest to the + pad are not bridged, hard to tell from the photo.
You mention 7.8ish V from the driver, I assume that’s a dynamic measurement on the + and - wires. Match’s graph “(here)”:More Emitter Test Results (xpg2, xpe2, mtg2) Updated 11-12-12 shows forward voltage of the XP-G2 starting at 2.8V (for only 200mA). I think your available voltage is too low.
I would do a voltage drop across each emitter to confirm. Use a DVOM, first + probe to red wire from driver, - probe to pad at 2:00 in the photo. Second, + probe to 2:00 pad, - probe to P+ marked pad just below center in the photo. Last + probe to P+ pad just below center, - probe to - wire from driver.
If I’m not mistaken, for a 2.8A driver you should be seeing approximately 3.0-3.1V per LED or 9.9V across the driver wires.
But then again I may be out in left field.
Good luck with it.
Also, if by any chance you may find a low value resistor (the value of the resistor is not so critical, let’s say minimum 10 ohms up to 100 ohms), in that case you actually will be able to do some simple tests in order to decide what was wrong there.
The resistor must be used to bypass each of the LEDs, one by one.
During the tests if the two remaining LEDs lights up, for all the three situations, than we have a low voltage converter.
If not all the three combinations will produce results, then maybe there’s a LEDs problem in the circuit.
Configuration for series in this image is good, I was looking at the OP image when I wrote my last post, sorry about that.
Thanks for the tip.
As I say, I’m getting confused here. If I change it parallel with 2 x 26650, won’t that be 8.4v to each led? Fine for a single li-ion setup, but not for a double li-ion? Or should the driver buck this down once there is ‘load’ on the system?
I’m also confused about what config will result in what current to each led. I was lead to believe this driver would supply 2.6amp to each LED while running from 2 x li-ion.
See my post was edited to make the first sentence i wrote irrelevant, again I was looking at the photo in the OP.
No I am not saying that you need the jumpers for either connection.
But your current setup is correct.
Some may wonder how is the current flow in series, I've drawn a green line for that.
If you rotate the emitter at 3:00 in your photo (post 48) and add the jumpers you will split the 2.6A among the 3 emitters or 0.87A/LED. To achieve 2.6A per emitter configured in parallel you would need a 7.8A driver.
Your current driver should maintain proper voltage to all emitters, in this case about 3.1V.
The LED’s don’t care how much “extra” voltage you give them. They are not over-voltage sensitive. They will use whatever voltage they need to do their job. They are current sensitive. So, if your driver is current-limited to 2.6A, you should be fine. The only issue with over-voltage will be if the driver can handle burning off the overhead, because it has to go somewhere. From what you’ve posted so far, it seems to me that the driver is well able to deal with it. However, if you want each emitter to get 2.6A current from a 2.6A driver, you still have to keep them in series. But, you’re going to need to give them more voltage than your 2S config, so that it will be enough to turn on the emitters!
Can you rely on a driver that has this description, it is not making sense, unless you want to attribute sense to it (make assumptions)
"Operating voltage:3-18V, up to 20V
Automatically buck: single lithium or double-lithium can promote 3-4XML boost,3-4 Lithium constant current constant temperature driven,Is reduced, the process is automatically switched No operator"
Thanks for the guidance.
Afraid it’s getting a little advanced for me.
This is what I’ve done, does it mean anything?
!http://i132.photobucket.com/albums/q11/300bhpton/Torches/CDF89506-2037-4B21-B4B4-FDF60E59B1B9.jpg
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Right, still a little confused. I specifically bought this driver because I was told I could run 3 LEDs each at 2.6amps using a 2 x li-ion input.
Are you saying this isn’t the case?
I don’t want to run each led at .8amp as there is simply no point, might as well go single emitter. And a zener modded Qlite would do better for 25% the price of this driver.
BTW - I bought this driver based on wights recommendation: