Quote Originally Posted by DreadedHermie
Weezard, the 15.1V scenario is just hypothetical. I fried the leds that measured this way. I just wanted to know how to invoke The Law.

I've got the replacements glued on but haven't wired 'em yet. Been up all night (common problem) and I'm 6 hours ahead of you. No touchee $$$ leds till later! :stoned:

Gettin a little gun shy?

Anyway, suppose I've got a happy voltage dialed in for my blues, let's suppose these next ones want 14.8V to draw 1.2A. Here's the question: if I want to dim the blues, can I leave the voltage set where it is and just dial down the current limiter? (That way I could just eyeball the changes and not have to measure.) Or is the proper way to do this by dialing down the voltage?? Does it matter? Would one way create any more waste heat, or stress components more than the other way?
Changing the current WILL change the voltage as long as the load is relatively constant. So 6 of 1...
But with a current limit supply, it's best to vary the voltage because the current limit will keep the voltage "capped".

I'll need more coffee to respond to your earlier posts.

Solar powered 'Zard
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