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ArcticMyst Security by Avery

What went wrong?

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So I got a LPC-826... hooked it up with 520ma. Lit up for about 7-8 seconds, then I heard a kind of squeal sound coming from my driver, turned it off. Then when I clicked it back on the laser was dimmed down to just about nothing. I believe the diode is dead at this point, it turns on but is completely dim (I assume that means it's dead). I've built a few lasers.... this is my first failure. Anyone have a guess as to what went wrong? Everything was wired correctly, power source was an 18650, diode was heatsinked, etc. Did I just get a bad driver or diode? Anywho, thanks for any input.
 
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These LPC 826 are relatively new, and while I may be wrong - they are not much different than LPC815, i.e. 520mA is too much current. Could somebody check up on that?

Squealing sounds from the drivers are usually a sign of a bad driver. I presume it's a switching driver, DC/DC converter. You should check the driver first. Which one is it?
 
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As Eud says.....
What kind of Driver were you using...:thinking:

Jerry
 
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It's one of these.
DIY 660nm Driver & Pill Module
Got it in a trade with some other parts. However, that is the driver survival lasers uses for their lpc-826 laser.... so I would assume it should be the correct amperage. It has 516 written right on it... so I assume they must test them individually. Of course... since it's all pressed and soldered into the aluminum, I can't even see the board to try and figure out what kind of driver it actually is and what's going on with it.
 
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I have never used such a driver, it seems rather expensive... well, plug and play for C6 host is an upside.

Say, how did you connect the driver to the diode? If you say "alligator clips" there's your problem.

Switching drivers must never be powered without a load on their output, even for a milisecond (and there's quite a lot of loadless miliseconds when you use aligator clips or other sorts of non-permanent connections).
 
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In principle if you have a good heatsink no problem with 520mA with this diode, in some cases can be pushed up to 600mA (not recommended anyway).

It can be anything, from a failure in the driver, or in the diode.

What I do not like is that you say that was dimmed down to just about nothing, is possible may be dead :cryyy:

Check wiring and welds, battery, etc...

If you have a test load also you could check the driver to see if work fine,
if gives the correct current, in this case 520mA.
 
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Fiddy

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flexdrive's ive had squeals when the battery cannot supply enough current!
check all connections to and from the battery and make sure your battery is half decent in internal resistance and is fully charged, also the protection circuit on the battery can be playing silly buggers.
 
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I have never used such a driver, it seems rather expensive... well, plug and play for C6 host is an upside.

Say, how did you connect the driver to the diode? If you say "alligator clips" there's your problem.

Switching drivers must never be powered without a load on their output, even for a milisecond (and there's quite a lot of loadless miliseconds when you use aligator clips or other sorts of non-permanent connections).


It was all soldered together. Afterwords I checked the connections, they look solid to me. I contacted survival laser, he said to send the driver back and he'll check it out and replace it if needed, and I guess I'll be ordering another LPC-826. If figures when I have a lot of spare parts and can build a laser cheap, it goes wrong and I have to buy more stuff.
 

Fiddy

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ive got the exact same driver in a C6 with a LPC-826 and it runs well!
have you tried using 2x lithium batteries to drive it? it seems the drivers run a lot better on higher voltage.
 

Garoq

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It's one of these.
DIY 660nm Driver & Pill Module
Got it in a trade with some other parts. However, that is the driver survival lasers uses for their lpc-826 laser.... so I would assume it should be the correct amperage. It has 516 written right on it... so I assume they must test them individually. Of course... since it's all pressed and soldered into the aluminum, I can't even see the board to try and figure out what kind of driver it actually is and what's going on with it.

The customer's email said it was purchased directly, not second hand. The driver assembly was tested and performed properly before shipment. Who knows if it was powered without a load like Eudaimonium said...
 
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Has anyone tested the lpc 826 and found a current that it consistantly dies at? 520mA is probably getting pretty near the threshold, and if he had a diode that wasn't quite up to par it could be a factor as well.
 
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Mine died @ 480mA - 3 Volt and didn't even runned longer then 2 hours total...
and susie told me ( 3 volt 450mA is ok ,but I think you can not run it long time )

i guess she was right lol
 
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Has anyone tested the lpc 826 and found a current that it consistantly dies at? 520mA is probably getting pretty near the threshold, and if he had a diode that wasn't quite up to par it could be a factor as well.

Ive tested a couple and both LED between 565mA and 575mA.

I Have been running them at 550mA since they came out.

Red is my favorite and most used WL so these laser get used the most. Not one has died on me yet at 550mA.

OP. Never use 2 cells in the Module Setup for a red laser. It was Designed for 1 cell.. It is different the the 405nm and 445nm set up.!!!

You probebly just got a Zombie. It happens. I use to get this with LPC-815's at 420mA only.
 
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The customer's email said it was purchased directly, not second hand. The driver assembly was tested and performed properly before shipment. Who knows if it was powered without a load like Eudaimonium said...

I wouldn't call it second hand, guy I traded with was my brother, lives in the same house, etc etc. He wanted it because he was hoping it would thread right into a host he had, it didn't, so I traded him for another driver I had. Basically I saw it from the point it came out of the box to the point it ended up in my hand.

Thinking about it now, I'm sure it could not have been powered with out a load because I soldered the diode to the driver before I even bought batteries for it. Also being that it originally came on at what appeared to be full power, then made a noise and seemed to die, I would think that is when something failed. If it was damaged before that, I would think it would not come on at all. However, I am not an expert on this, hence the thread.
 
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Fiddy

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Ive tested a couple and both LED between 565mA and 575mA.

I Have been running them at 550mA since they came out.

Red is my favorite and most used WL so these laser get used the most. Not one has died on me yet at 550mA.

OP. Never use 2 cells in the Module Setup for a red laser. It was Designed for 1 cell.. It is different the the 405nm and 445nm set up.!!!

You probebly just got a Zombie. It happens. I use to get this with LPC-815's at 420mA only.

Mine died at 550mA after 2 months, didn't use it much either.
 




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