Help with bad cree R5 modules

[jjblomquist]

I have been modifying sku 32953 Cree XP-G R5 320-Lumen White Light LED Drop-in Module (26.5mm*29.3mm/18V Max) form DX for some Dive lights. I test each module when I get it. Some times just after a few minutes of runing the light will dim out or start to flicker or if I shake then they go all the way out. Even after testing and I send then out 10% or more are DOA so I have to send a replacement.
Is this a driver issue with these or bad soldering. Any Ideas
I have 10 dead R5 mods here and 10 R2s
Any help would be welcome
Thanks

 

[TorchBoy]

I have been modifying ... I test each mod when I get it. ... Any Ideas

Idea 1: Fix your spelling and grammar.
Idea 2: How come you're "getting" the mods if you mod them yourself?
Idea 3: I honestly don't know if you're having trouble with these drop-ins before or after you mod them.
Idea 4: How are you modding them? (And is that the problem anyway?)

 

[jjblomquist]

Idea 1: Fix your spelling and grammar.
Idea 2: How come you're "getting" the mods if you mod them yourself?
Idea 3: I honestly don't know if you're having trouble with these drop-ins before or after you mod them.
Idea 4: How are you modding them? (And is that the problem anyway?)

I just take the 2 springs off the drop in. Then add a spacer to the front of the reflector.
And yes I'm a bad speller

 

[gcbryan]

I have been modifying sku 32953 Cree XP-G R5 320-Lumen White Light LED Drop-in Module (26.5mm*29.3mm/18V Max) form DX for some Dive lights. I test each module when I get it. Some times just after a few minutes of runing the light will dim out or start to flicker or if I shake then they go all the way out. Even after testing and I send then out 10% or more are DOA so I have to send a replacement.
Is this a driver issue with these or bad soldering. Any Ideas
I have 10 dead R5 mods here and 10 R2s
Any help would be welcome
Thanks

I'm assuming that you are modding a dive light and not the drop-in. Is that correct?

Those drop-ins more than likely don't have proper drivers. Due to the low vf some are being overdriven and are burning out. If they aren't burning out then perhaps they do have proper drivers and are just soldered poorly.

I think the problem is the former rather than the latter however (based on some personal experiences).

Edit- I just saw your answer to the first question. We were posting at the same time.

 

[andrewnewman]

I'm pretty confused too. The part you specify is a DX drop in. If you are "modifying" some other light (PLEASE specify!!) by putting this drop in in it, it sort of barely qualifies as a "mod". If this is the case and you are having a high failure rate with the DX product then either take it up with DX or find one of the (literally!) dozens of other P60 drop in suppliers that use CREE LEDs and do business with them. I don't see how speculating on the failure mode open endedly is helpful.

If you are, instead, somehow modifying the DX dropins, you should really specify exactly what you are doing to them.

 

[gcbryan]

I just take the 2 springs off the drop in. Then add a spacer to the front of the reflector.
And yes I'm a bad speller

It's hard to address the flicker when you shake it without seeing your build. The springs that you are removing are designed to prevent that in a P60 host.

 

[TorchBoy]

Are you testing the drop-ins before and after your alterations, and again after you install them in your dive lights? Where is the problem surfacing (no pun intended)?

 

[jjblomquist]

I have made about 300 of these whith the R2 and the R5 also just started The P7 drop in. I fit then in to the UK SL4 and SL6 dive lights. Also the Halcyon Scout. So the voltage is from 4.5 to 9v in the lights.
I would put a picture of then up but I don't see away to attach it.

 

[alphazeta]

To be frank, given the lack of a thermal path of your dive hosts -> I think you have experienced a relatively low failure rate with those drop-in modules.

Some of your failures could be attributed to a sample of the emitters having lower forward voltages than the others (=higher current & ultimately more heat.) Other variables could also be at play (i.e.- insufficient thermal contact between the emitter "star" & module base.)

Were those ~300 prior lights all of the Cree XP package? Or were some of them using the more robust XR-E package?

-AZ

In reference to attaching pictures on CPF, the actual pictures will have to be hosted offsite.

 

[LEDninja]

There are a lot of bad reports of the module.
http://www.candlepowerforums.com/vb/showthread.php?t=270143

And flashlights that may be using the module.
http://www.dealextreme.com/details.dx/sku.35075

 

[HarryN]

I know what you are doing sounds like a good idea, but in reality, a drop in that costs less than $ 50 is most likely not reliable enough for a diver. You are seeing this already in the high rates of "incoming" falures, much less on someone who depends on a light to work at depth.

Also noted above is the thermal path challenge. LEDs produce heat that must be conducted out of the light. Plastic bodied lights are exceptionally poor at this, in spite of their excellent design for most underwater use. You might get away with a 1 - 2 watt light engine package, but the DX ones usually burn off nearly 50% of the power in the driver

In that configuration, a 5 watt XP-G is really using 10 watts - far beyond the ability of a plastic bodied light, even underwater.

I do commend you for working with LED drop ins and helping to get them into the market.

 

[yellow]

20 duds out of 300+ modules ...
... and You do not feel lucky?


Better to calculate a "1 out of 3" ratio (of one being very good in the end out of three orderd)
... at least thats what I have personally observed.

 

[jjblomquist]

There are a lot of bad reports of the module.
http://www.candlepowerforums.com/vb/showthread.php?t=270143

And flashlights that may be using the module.
http://www.dealextreme.com/details.dx/sku.35075

Thanks for the Links very usefull.

 

[jjblomquist]

I know what you are doing sounds like a good idea, but in reality, a drop in that costs less than $ 50 is most likely not reliable enough for a diver. You are seeing this already in the high rates of "incoming" falures, much less on someone who depends on a light to work at depth.

Also noted above is the thermal path challenge. LEDs produce heat that must be conducted out of the light. Plastic bodied lights are exceptionally poor at this, in spite of their excellent design for most underwater use. You might get away with a 1 - 2 watt light engine package, but the DX ones usually burn off nearly 50% of the power in the driver

In that configuration, a 5 watt XP-G is really using 10 watts - far beyond the ability of a plastic bodied light, even underwater.

I do commend you for working with LED drop ins and helping to get them into the market.

I do add a nice brass bushing that covers most of the module also I just started to add that Alunimum tape around the pill so it touches the brass and around the front so it touches the glass in hopes of getting some cooling from it. Thanks