flexmod P3.3 catastrophic failure

[Draco]

I wanted to pass this info past you guys just to triple check my laser, yesterday i was running my home made open loop scanner being fed just audio and had the laser powers set for white, i had set up a new flexmod P3 to run a PL450B blue laser in a heat sinked housing and the flexmod also heat sinked
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it had been in service for less then 30 days, run from a bench supply with a VCC of 12 volts and the modulation set for about half power, then last night i notice the blue go out and the over current light go on, on my supplies, one runs at 12 volts and the second for the modulation voltage with a common ground as i have done on my 1.6w version with an identical driver, nothing was warm and i checked for shorts, all the normal stuff and with no load, no modulation and with grounded modulation, "i tried all this in different steps", when i ramp up the voltage and hit 5 volts it goes into a runaway past 6 amps with an open load, this has the 7 second soft start enabled and has never been modded. When this failed it also took out the laser and oddly the FET does not test as shorted nor does the input, the red light comes on as it should for no load but still sucks amps of current, i contacted Innolasers and all i got back was "We will answer as soon as possible."

I am hoping for some peer review here to see if i made an error but i have set up at lest 6 of these and never had them fail and and have had one running a PLTB450B for many months now.
i was also wondering if any of you guys have had a catastrophic failure like this, from this driver?

[Draco]

Innolasers is now starting to push my patience, they have yet to give me any more info and this is starting to really annoy me, and as i am sure most know that dragons tend to get a bit growly over something like this, i like there drivers but there customer services is really starting to get under my scales so to speak.

I am also thinking that no one has offered any peer advice that i did indeed have it connected correctly and correctly set up, even the heat sink is over kill for the load, if they would give me a schematic i would say fuck it and repair it my self, but as of now it's untouched, i had hoped they would give me an RMA by now so they can get this unit back and figure out what went wrong, i am almost sure it's not a fault of the final FET and that it has a failed op amp or the on board microcontroller is at fault. I know it's only 35 bucks but i am on social security disability so 35 bucks is not a trivial amount of money for me, that was my whole budget on non essential items, i was going to buy another this month but that is on hold now, i have had faster response from the crappy companies out of china, one of the reasons i picked this company is at-lest part of it is in country work and as i understand the engineer that designed these is a member of this forum.
this is indeed frustrating

[dkumpula]

Hey Draco,

I've had about a couple dozen Flexmod P3s in service over the years, but I haven't encountered the problem you are describing. I've had several failures of various types (at least one was my fault) with the beam suppression version of the FlexMod. (The non beam suppression version worked fine in my experience.) The most common problem was beam suppression not working at all.

DrLava takes quite a while to respond at times, so I would continue pinging him every few days or so until he responds.

Going forward, you might want to take a look at the drivers sold by x-wossee on E-Bay. He sells a 3Amp and a 6Amp driver although it appears that he doesn't have his 3Amp listed at the moment. I've purchased over a dozen of the 3Amp model and have had no problems. Not to mention, at US$24, they are a great deal. The only downside is delivery takes about a month between Russia and the US these days.

-David

[CDBEAM]

Draco, As Clickamouse will verify....I do not care for the P3 !! I have had problems over the years.....and prefer the drivers from Dave at LSP...( If he would only offer a three driver config !!!!! )
.
Anyway....I assume a bench supply was supplying the P3....I have a suspicion that any driver being supplied by a bench supply...MAY....may....may fail or fry the LD....IF the current on the bench supply is changed....while the LD is powered up !! THIS is my theory....for I think I have had more than one issue when I have done this !! Perhaps just a coincidence !!! I know squat about electronics !!! I barely know squat about squat !!!
.
I imagine another member... with an electronics background could chime in....and correct my speculation ??? or not !!
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CDBEAM=======>

[absolom7691]

My experience with the Flexmods has been so-so. They are a solid driver but I have blown a few blue diodes using them. Once I started putting Lasorbs on my diodes, I have not had any problems. I don't care for the "beam supression" at all and because of that, I will be switching all of mine out.

If he would only offer a three driver config !!!!!

YES!!!! Either a tri-driver or a single one. It's a waste for a 3 diode projector to buy two 2 ch drivers.

[Draco]

ok, thanks for the info, should i try sending DrLava a pm in forum or just though his web page?

[Draco]

Draco, As Clickamouse will verify....I do not care for the P3 !! I have had problems over the years.....and prefer the drivers from Dave at LSP...( If he would only offer a three driver config !!!!! )
.
Anyway....I assume a bench supply was supplying the P3....I have a suspicion that any driver being supplied by a bench supply...MAY....may....may fail or fry the LD....IF the current on the bench supply is changed....while the LD is powered up !! THIS is my theory....for I think I have had more than one issue when I have done this !! Perhaps just a coincidence !!! I know squat about electronics !!! I barely know squat about squat !!!
.
I imagine another member... with an electronics background could chime in....and correct my speculation ??? or not !!
.
CDBEAM=======>

the bench supply i use i don't change anything on it while it's running a laser driver, the main supply is an older Kikusui PDM35-3 that allows you to turn on the output after the supply has stabilized, the other supply of lesser quality i was only using it for the analog modulation input and was at about 2.5 volts and all of this was running about an hour before the failure occurred. i think the only reason i did not have the thing catch fire is both supplies have over current shut down, i only played with adjusting the voltage after the failure happened, that's why i know it goes into run away only after 5 volts and above is supplied to the unloaded P3.3, with out the laser connected it should have never even started up, the red led that indicated no load or an open interlock was even on, the main FET should have never had a drive voltage, i still suspect it has failed but with out a schematic i cant do squat

I will be switching to a fixed output power supply in the future, i have a few that i trust that supply more then enough current.

thanks again for the info

[lasermaster1977]

Hi Draco,

I feel your pain for what happened and am sorry to hear about it. I know a fair amount about electronics and purchased three P3's a while back to power my laser diodes but life happens and I haven't gotten very far on it due to other demands. In my tests however, with LD's and the P3's, I only used a voltage regulated, with an adjustable current limited supply. A word to the wise would be to only use a regulated, current-limited power supply when powering a FlexMod P3 or a laser diode circuit, making sure the current-limit control is set to at or below the maximum allowable current for the device. That said, a voltage regulated power supply can only regulate the voltage and although your supply does current-limit to 3.0 amps it does not have an adjustable current-limit for either voltage rail, + or -.

A series resistor of proper power rating might be a minimal consideration to limit current spikes to a safe level for the P3.



I know one has to use what one has, though.

[flecom]

nobody is going to put a bench/lab supply in their projector... current limiting to the max diode current seems a little silly since, you know, that's the flexmod's job...

anyway I have had several flexmods go up in flames so I gave up and sold most of mine

[Draco]

had i not had this connected to a current limited supply it would have caught fire and destroyed the friken power supply, so your "little silly" idea would have resulted in further damage down the line, mine did not catch fire because i limited the current to 6 amps and the supply shut down.
In any electrical drive or circuit you must have some form of current limit, at the minimum a fuse is mandatory on the power buss. you can't depend on the built in fuse or over current in some cheap switch mode power supplies.
On that note i would not build the supply into the projector anyway so it's a moot point to where the 12 volts(in my case) comes from, be it a battery, bench supply or a unicorn's ass.

what is really pissing me off is the lack of service from his company, i will never buy another one from him