First Impressions 2019 RRT-01 w Red 620nm XP-E2

[moderator007]

@jon_slider

In any case, I can tell you, and anyone that cares to listen, that the Red LED at 250 lumens is ridiculously bright, I would never use it at that level. But I did, just to see if I could melt the LED… so far, no issue.

I was curious about running this led with the 2019 driver until I came across djozz wonderful red xp-e2 test.
Apparently the red xp-e2 has a steep vf slope compared to the current.

testing a red XP-E, and comparing it to a red XR-C, 22/4/'14: XP-E2 results added in post #32

[image] I did the red XP-E2 (630nm) test (with big thanks to MRsDNF who sent me a few leds for free, coming from Cutter), above stereo-picture is after the testing. I also re-tested the red XP-E because it was sitting there reflowed on the Noctigon already, and I wanted to re-check everything, now that I use a new power supply. Below are the results. BTW: the XP-E results match reasonably the former results of that same led in the OP, so my two (both lineair) power supplies more or less agree o…

So I’m guessing that’s the reason it worked without melting anything. Looking at the graph suggest this led will work great with this driver or almost any driver that has a output of 4.2v or less. Even direct drive looks like it would work from a single cell, even though it has such a low rated vf. I would have never guessed that without djozz testing data. Thanks for the test djozz :+1: .