Quote Originally Posted by DreadedHermie
I think those Mean Well's I want are CV and CC, if that makes any difference.

Let's say I have 13V @ 4800 mA going to 4 blue LEDs in parallel. Each blue is drawing ~1200mA, yes? Now, I switch one blue out of the circuit. Do the remaining 3 blues divide the 4800mA if the voltage remains at 13V?

No.
If the voltage remains constant, each led will still draw 1.2 A. for a total of 3.6A.

I = E/R
If we change R. and keep I. constant, E. must change.
If E. is held constant and we change R., then I. must change.
etc.
It's the LAW.

That's the part I'm not sure about. Maybe a safe way to check it would be "backwards," like setting things safely for one LED and switching a second one INTO the circuit, and seeing what the driver does in response?? :stoned:
Once you've tested and recorded Vf. and I. for each individual LED, you will know if one will try to "hog" the current.
(A led with significantly lower Vf. will draw more current than it's neighbor.)
That's why we never try to run paralleled leds at or near I. max.
With luck, all your emitters will be within .01 V. and it will not be an issue.
So, bring them up one at a time to 1.2A and record the Vf.
We can then make minor adjustments as needed.

Gotta run.
zooooom.
W.
Weezard Reviewed by Weezard on . Calling out to Weezard for LED advice My friend, I've read your stuff here and at Steve F.'s site. I want to build a dedicated flowering lamp using Ledengin 15 watters. (4 reds, 1 blue, and possibly 1 warm white; LM 317's so I can tweak the ratios.) Essentially, a copy of your 4+1 cake pan lamp but built on a 4 x 18" finned heatsink so I can see what's going on under it.) If I were to post my picks for power supply, resistor ratings / values, etc., would you critique and perhaps offer some guidance? I have already purchased Rating: 5