just destroyed three XM-L2’s on 20mm Noctigon boards and 2 x 5.5-12volt 5A drivers.
The LED boards were stuck down to a block of alloy with Artic Silver, plenty of cooling but each LED lasted about 30 seconds. after cooking the second LED, then the driver board fried.
So I have physically smashed up the rest in bloody annoyance. …ggrrrr
waited a month or more for all these parts to arrive from Mountain electronics, then it has been about 2 months before I got around to the job, and within half an hour I am back to square one. No parts and two dead bicycle lamps.
I’m building up an e-bike and the voltage dropper to run other stuff is 12 volt. so wanted a 12 volt driver.
From what I had read, the LED should have been good for 5 amps with good heatsinking …which they did have.
But no …anouther f**k up on my part.
this bike buidl has been goin on for 8 months now, and I can continue till I get the light wiring finalised. And now I am going to have to order and then wait another month or more to get replacement parts.
I know that feeling. You wouldn't be talking about this 5A-2S3S-DRV driver would you? This is a good driver but I burnt it up because I ran it with no heatsinking. Fastech has the same driver only it is a cooler running 3 amp version. I'm testing one potted with a chunk of aluminum right now.
Yep, I emailed him about that driver and he said they really need heatsinking. I love Rich and he will always get all my extra money but he needs to change the word "should" to "must" where he describes that driver when it comes to heatsinking. So I just went to FT and bought the cooler running version. There is a link I posted above.
Now that I think of it that driver did pop an xm-L2. He replaced that for me and offered to replace the driver too.
Here is a picture of the FT version I just potted. I've already tested it on high for 5 minutes and it is doing well, still hot as hell, but running good. I intend to pot it further into the inside of my Supfire L3 pill cavity.
Heatsink the driver ?
Is that what the potting compound does?
The LED was heatsinked to a good alloy case, via a block but obviously not enough.
Maybe it was the driver that went first ? And sent 12v direct to the LED.
Thanks for the link to the others.
So far most have my conversions have been failures, probably 75% failure rate. Just dumped 15 LED’s and a similar number of drivers. Beginning to think this shit is not for me. It is sctually far cheaper in long run just to go out and spend $400-500 on a quality one to start with.
Nice find. Think I'll take a couple too. Looks like the same driver only with the "correct" inductor installed on it. Heatsink it! It will blow if you don't. This one too like rich's is running at 5 amps. I won't trust anymore of these 5 amp drivers without encasing them in a block of aluminium.
Unfortunately, for what we are paying for this crap, you need to mod them to make them work in the real world. Seems like they design these circuits for us, test them for 5 seconds all call it "done".
Well I have just dumped a load of other drivers too, 1.5 v , 4.2, all sorts I bought new from FT in the past but never used. never am going to use them, they are just sat here. all in the bin…and to save myself trying to rescue them later I have mashed them all up with a hammer.
What is the compound you use to pot them? . I may have to get some. I guess
JB Weld mixed with a little of this. I just started using it and am VERY impressed. And, if you have a Harbor Freight near by, their epoxy is just as good and occasionally goes on sale for 99 cents(Memorial Day). I headed there this morning to pick up the rest of their stock..
That is a bugger , but I am so glad it is not just me!
I don’t know what to do now.
I am tempted to try the 3 amp ones.
The homemade potting thermal potion paste, um may try that. no Harbour Freight here, wrong country, . I actually live on a small island , 12 x 8 miles (Jersey) and not a massive deal of choice, so an e-mail order needed.
So if i have to order something, is there a specialist ‘proper’ thermal potting compound that will do a better job. ?
Well, I know this one works. Had it in there previously, but only 2.8 amps. Guess what? Its going back in...
However, that potion is working very very well, strongly recommended. JB weld and some of that pixie dust I mentioned above. And of course, you need a reliable driver. There aren't any unfortunately >3.5amps on 2 - 3 cells.
With silicone thermal cubes I have very little issue with the 5 amp buck driver from Mountain besides the high pitch whine.
Did you verify that your voltage reducer is actually bringing the voltage all the way down to 12 volts? I’m not sure how picky the driver is but if you measure over 12.5 volts maybe that is the issue.
What about 5amps? RMM has been testing one for awhile. He released the parts list so you can build your own, or wait till he starts selling them pre-built. (that could be awhile)
