I guess the more power you push through the diode the more stress you put it under…still…it should have lasted longer than that…From NEJE website -
“NEJE has key core technology to control the effective life of the laser diode to 10,000-20000 hours, and promises a 2 year warranty! If your laser have problems, You can get it for free from the store you purchased, or contact the official service channel：service.nejetool.com”
Might be worth a punt!
alternatively…
It does sound like it might be the output stage in the regulator that has blown and not the laser diode itself, would you be up to a little investigation and do you have a reasonable bench power supply?
If you take the four screws out that secure the fan on the top of the laser module you will find on the bottom of the regulator PCB a 4 pin plug - red is to LED+ black is to LED - and the two green wires are the thermister for temperature measurements. It is a bit tricky without knowing the exact diode that NEJE uses but if you current limit your bench PSU to 1 Amp to start with and start with the voltage set to minimum and slowly ramp it up you will soon see if the diode is ok or not. I would think go no higher than 4v. If the diode is ok perhaps something like this will return the laser to service?
Sadly, I have confirmation that I am the culprit. Later last evening, I was engraving a photo and I got up out of my recliner, walked to the machine, simply touched the X-axis extrusion, and got zapped. All X motion immediately stopped and no amount of resetting or attempted jogging would start it again. Took the DRV8825 off the controller board and replaced it with a spare that I had close by… and was immediately back in business. That pretty conclusively proves to me that static was the reason for the laser’s demise as well…
I did get a Neje 6W laser module with that order (that I haven’t played with blown up yet) … but what I zapped was the BX20 laser module from the Vigotec engraver machine. Like you, I suspect the laser diode itself is probably still okay… and a component on the laser’s controller board is now bad. In fact, it still seems to operate – on/off and variable intensity – but simply has no real power.
I really do appreciate all the troubleshooting tips, Mike, and think you may well have pegged the problem (blown output stage). I may piddle with it some more later, when I’m in the mood and a bit more courageous… but, right now, I’m bummed about all the static electricity and afraid to touch anything. Same house, same recliner, same clothes, doing the same kind of stuff I’ve done for the last 50+ years… but, right now, sliding in and out of my recliner is charging me up big-time. We’ve had some strong storms, with lots of lightning, roll through the area over the past few days – in fact, a nearby lightning strike blew out my kids’ (next door and 100 yards up the hill) internet connection last Friday evening – so maybe that’s somehow got the atmospheric conditions just right for me to charge myself up so easily.
Anyway, I’m really jumpy right now and afraid to touch anything. This is all new to me and I’m struggling to think of things I can do alleviate the problem… changing shoes/slippers, clothes, shoot the dog, spray down the recliner with anti-static spray, etc. Maybe I need to get a good anti-static mat and set up a workstation before I go handling any more of my electronic stuff…
Recommendations? Ideas? I’m appreciative of any help thinking this through…
If you ground the X axis, and then just get in the habit of touching it before anything else when you walk up, it will discharge the static you build up while walking around the room.
I would not be so sure the static actually toasted the laser either. It could have, if where you shocked took a path through the non-ground parts of the laser to find ground. But that’s not the only explanation. FWIW, static isn’t a new problem and if someone sells a product that can so easily be destroyed, then they have at least some culpability. But early burn out from driving lasers too hot is a common complaint. That seems more likely to me.
But yeah, grounding the metal things, like the diode case, and the rails, would probably be enough to hit those first on the way to doing damage to any of the sensitive parts. That’s something that is common in real products that we skip in our sheds.
And if David didn’t lounge around in a cashmere smoking jacket and have wall-to-wall deep shag carpet for his lady friends to roll around and frolic in, he wouldn’t have such static issues…
You do have lady friends to roll around and frolic in your deep shag carpet, right?
In the electronics industry, static is a for-real problem. All lab workstations were set up with anti-static mats and wrist straps (which were mandated and religiously used), IC’s and sensitive components are shipped and stored in anti-static sleeves and packaging, and boards and components really can be damaged by static electricity. Even with all the precautions, static damage was not uncommon or unheard of…
The laser has a low-power switch on it to turn on the beam at very low power… for focusing and positioning the tool head. I was toggling that switch often at the time and I’m pretty sure I got zapped a few times reaching for it. There’s no doubt in my mind that I killed something on the laser’s controller board by touching it one time too many. I was also not driving the laser at full-power or for prolonged periods… I was engraving at ridiculously low % levels to try to get a handle on the feeds/speeds and power settings to get results similar to those I get with the 2.5W laser.
Ah, there’s the rub… I am a creature of habit and that hasn’t been one of my habits. However, much like a dog reacting to a shock collar, I am starting to get the point…
Also if you ground yourself through a big resistor, say 1M ohm, then it’s always painless whether you have a charge or not, and it’s easier to get in the habit, at least for me.
Lounging around… yes. Old flannel shirt (suspicious? but I’ve worn it for years with no problem) rather than cashmere… to keep the chill off my shoulders. No shag carpet… fake hardwood floors with a few small throw-rugs. Widower, after 44 years of difficult marriage, not real excited to get too entangled again. Not totally averse to the idea… but it would have to be a special lady and special relationship. Not likely… so, until then, I shall remain unkempt and quite grody.
Thing to remember with static is that it is YOU giving the equipment a shock…not the other way around. run a ground wire from your chair frame (it is metal isn’t it?) to an earth point…usually an earth pin on your mains plug…get the right pin :-))
I think I’ve got the static a bit more under control now. Did two things: 1) started a humidifier in the room, and 2) bought a can of Static-Guard and sprayed down my recliner. That did seem to help and I’m once again able to touch my machines without quite the anxiety I had… though, like the dog and shock collar, I’m now “semi-trained” to think a bit more, before reaching for something on the machine.
Look at my avatar (that really is me)… do I really look like the Ann Margaret type? When I interior decorate or accessorize, it’s this machine here… that machine there… dismantled machine parts in that corner… new machine assembly station right here. Oh, dang! Where am I gonna put my recliner and TV?
At the time of that photo (my only selfie BTW), I was living/sitting/soaking in my grandparents old farmhouse in mid-winter… built 1950-ish, in rural East Texas. The 5-room uninsulated pier-and-beam house had a single old Dearborn heater and I never lit it until it got into the 40’s… primarily just to keep things from freezing. Since I lived alone, I really didn’t mind bundling up, covering my bald head, piling on the blankets, and cutting off the water except for brief periods… even when the temperatures got down into the teens, or single digits, on rare occasions. Good times… camping indoors!
I guess the more power you push through the diode the more stress you put it under…still…it should have lasted longer than that…From NEJE website -
