I thought so too, but considering that the solder bulges slightly up it worked without a problem. The led got pulled into it’s place once the solder started to flow.
I’ve had (the start) running yesterday without any issues. Then I decided to test the limits…
Hi again, your LED should be on it’s way to Germany as we speak.
I’ve run a test to see if these leds have the same issue…
After pushing the test-unit (the one on the DTP star) to 1.7A i had to stop the test, as I did not have proper isolation of the rest of the lab from UV bombardment.
The die seems unaffected. The star temperature reached around 56°C
Those are pretty cool, and the combination with a readily available DTP board makes them interesting.
Tempted to buy one but $20 for one led, however good the price, still makes me think twice 
!
Djozz, cant you send me some translucent S2+ thingies, and i will send you one of these 
That is too good a deal because I got those for free from Simon. But send me your address and you will get some anyway. (and that reminds me that someone else asked for a few of those as well, so I will have some shipping to do )
I just got mine today. Very fast shipping! Thanks!
djozz, PM sent. I’ve ordered some S2+ hosts from GB for modding. Feel free to ship away any S2+ parts you don’t want to keep 
The_Driver, wow that was indeed fast. Any plans on how you are going to mount the LED into your host? I’ve modded a 348 with one of these where I just soldered the LED to a rectangular copper bar 2x3x6mm and then glued to the pill…
I’ve got some more playing to do with these today. Any wishes what one should do to a de-domed or, should I say “de-windowed” UV led? :smiling_imp:
Forgot to annotate the photo.
The small die on the anode side is apparently the ESD/TVS protection diode. That fella ensures that this expensive diode does not get zapped by the static. Ain’t that sweet…
Thanks Valor, I will get you a few nice emitters for your S2+
This will soon need it’s own separate thread
I’ve had some time to prepare a test of the same led at 1700mA and leave it running overnight. The thermal performance looks very promising.
I’ve then had the led running at 2000mA for an hour and it stabilized at 79°C. That’s at 285% of datasheet figures.
The power usage seemed to remain uniform despite running warmer.
Voltage and current has been logged via an Agilent 34970A data acquisition unit. I’ve ordered a set of Omega K-type thermocouple to cover temerature in the logged data…
No visual deterioration either
Mine arrived yesterday, thanks for yor fast shipping!
That graph screems for added output data. I will see if I can add that (but no promises because it is hobby ).
Cool. It was primarily done so that I don’t miss the burn-down moment. But luckily the led coped with it well.
A friend promised to lend me an industrial UV power meter sometime next week. I hope to do some absolute irradiance (W/cm2) measurements for stock as well as “overdrive” currents.
No need for you to risk your LED outside its specs
Doing measurements with an actual UV power meter is way cool! Looking forward to that.
Finally received two EIT SpotCure UV Intensity Meters and figured I need a way to collimate the light in order to make accurate readings.
After some experimenting I decided to go forward with a simpler setup: mounted a 18mm reflector (laying around) and centered with some rubber o-rings. I hope this way I can minimize the spill.
The measurements are now relatively consistent within few counts, based how I align the flashlight.
The UV meter has a large “Start” button which has to be pressed while measuring. Releasing the button stops the process and keeps the screen on, showing the latest reading for 3 minutes. I’ve modded one of the meters for a “continuous” reading to make the measurement easier…
Since these meters measure the irradiance, the unit for the readings is Watts/cm². I’ve yet to find a way to convert these into a ballpark raw power in Watts before we can compare the measured output to the values advertised in the datasheet.
Here’s a reading out of a new & freshly modded Convoy S2+ with one of my LEDs mounted on a 16mm aluminium XHP50/XHP70 base, and the glass replaced with 2mm ZBW2 filter. The measurement is done with the stock driver set to the “HIGH” setting.
Some more statistics to follow…
Finally some more data
Here are some irradiance measurements with and without ZBW2 filter.
The “start” of the measurement shows the instantaneous reading, the “end” is the reading once the output of the LED&flashlight stabilized (3-5 seconds)
We have our first martyr in our research…
This one was mounted on a 20mm alu. MCPCB, zapped at 4.5-5A pulse
Cool picture! I feel sorry for the led.
Do you have any further data on up to which current it did survive?
And the S2+ driver was a 2.8A lineair driver?
Was the MCPCB a non-DTP board?
I have not played with the led I got from you, but look forward to make a nice mod with it (will try an output test as well)
Thanks djozz,
I am still waiting for me new Omega temperature probes plus I ordered a wideband photodiode…
Once the new data acquisition setup is ready for loging temperature and relative power output I will proceed with overdrive testing. The absolute irradiance reading will be taken manually at certain steps.
The S2+ host is with a 2.1A linear driver (6x7135). I will probably use an S2+ head (driverless pill, reflector and the stock glass) for the mensioned test. This might be esier to work with and will provide OTF measurements
The dead diode was on a non-DTP aluminium board free-hanging in the air
Retook the photo with a new lens and an extension tube :sunglasses:
