XHP50 When does the magic smoke come out?


I’m wondering if anyone’s found the upper limit one XHP50s in a well heat-sinked light?

I just built a Shadow TC500 with a 6V XHP50 and FET driver from Vestureofblood. The XHP50 is on a Maxtoch 31.5mm DTP MCPCB soldered to a copper disc, polished and screwed down to the head.

I initially tested with protected NCR18650Bs and found 4.5a at the tailcap, nice! After running the light a while I swapped in Samsung 20Rs and see 7.6a and a whole lot of light!

The head starts to warm up within seconds of turn on so the thermal path seems good but I haven’t let it run more than 20-30 seconds on high yet.

So does anyone have an idea of where the upper limit is on the XHP50? Cree datasheet says 3a but we all know there usually loads of headroom.

As a general rule, if you search for “[emitter] crash test” here you’ll find what you’re searching. I saved you the trouble this time:

Cliff notes version: not for a long way from where you are, but they peak in output at about 8.5 so you really don’t want to exceed that.

From this thread, its a good read :slight_smile: Cree XHP70 up to 4022 Lumens and XHP50 up to 2546 lumens - Multi-die leds.

Scroll down a bit, there is a graph.

Cheers David

Edit, I must learn to search and type quicker :stuck_out_tongue:

I had searched for XHP50 output, max amps, etc. finding the thread you both linked but did not read through all 986 replies.

I find it interesting that the link emarkd included (page 10) starts at reply 501, I see no mention of max amps on that page up to reply 550.

The link pommie included (page 9) starts at post 451, scroll all the way down to post 500 at the end of the page and no graph.
I think I found the graph at reply 313 on page 7.
I wonder if changing the maximum number of rows per page has rendered links inaccurate.

At any rate, looks like I’m just where I want to be with my XHP50, thanks for the responses.

The second link I posted goes directly to post 274, which contains the graph, its a long post so you have to scroll past a few images.
The main thing is you found it.

Cheers David
Edit: just to make it a bit easier Cree XHP70 up to 4022 Lumens and XHP50 up to 2546 lumens - Multi-die leds.

Yes the max rows per page function has been a subject of concern for creating links on this website for quite some time. I think the suggested recourse is to pour up a Trappist Quad and read the thread.

Here is the graph,

I still advise reading the whole thread, it has a lot of useful info.

Cheers David