djozz, PM sent. Iāve ordered some S2+ hosts from GB for modding. Feel free to ship away any S2+ parts you donāt want to keep
The_Driver, wow that was indeed fast. Any plans on how you are going to mount the LED into your host? Iāve modded a 348 with one of these where I just soldered the LED to a rectangular copper bar 2x3x6mm and then glued to the pillā¦
Iāve got some more playing to do with these today. Any wishes what one should do to a de-domed or, should I say āde-windowedā 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. Aināt that sweetā¦
This will soon need itās own separate thread
Iāve had some time to prepare a test of the same led at 1700mA and leave it running overnight. The thermal performance looks very promising.
Iāve then had the led running at 2000mA for an hour and it stabilized at 79Ā°C. Thatās 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. Iāve ordered a set of Omega K-type thermocouple to cover temerature in the logged dataā¦
Cool. It was primarily done so that I donāt 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 āoverdriveā currents.
No need for you to risk your LED outside its specs
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 āStartā 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. Iāve modded one of the meters for a ācontinuousā reading to make the measurement easierā¦
Since these meters measure the irradiance, the unit for the readings is Watts/cmĀ². Iāve 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.
Hereās 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 āHIGHā setting.
Finally some more data
Here are some irradiance measurements with and without ZBW2 filter.
The āstartā of the measurement shows the instantaneous reading, the āendā is the reading once the output of the LED&flashlight stabilized (3-5 seconds)
I am still waiting for me new Omega temperature probes plus I ordered a wideband photodiodeā¦
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
Iāve got your parcel with the high CRI and UV leds today. Special thanks for the Lite-On 365nm.
A few more S2+ flashlights are on their way, one of them will host this Lite-On. It would be nice to have it for a comparison.
I finally used mine. I put it in the Convoy S2+ (mine was actually the UV variant) mounted on a 16mm Sinkpad for XM-L (5050) LEDs. It doesnāt fit perfectly, but it centered nicely after a few tries with lots of added flux. Vinz also did this here. Unfortunateley I had to file the edges of the pcb and also enlarge the hole of the reflector.
Now it works and I am driving it at 700mA. The host becomes warm to the touch after 2-3min. It could probably tolerate 1A, but I wouldnāt go much higher than that.
That one thing I still want to do is sand the glass to make the beam more floody. The small die turns the S2+ into a thrower with a tiny spot.