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vapealone

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  1. BTW, I have made my mini monster (38mm x 50mm x 85mm) from scratches but you can buy (or will be able to buy soon) small, professionally designed 3 x 18650 mod for yourself if you wish e.g. the Wismec Reuleaux with dimensions not much different from the Lavabox (Reuleaux : 40mm x 50mm x 84mm vs Lavabox: 28.15mm x 46.19mm x 94.87mm)
  2. For I don't do high power I figured that multiple Li-Ions and their extended capacity would suit me better even with its significant voltage drops And with this mod, my whole thing about the cutoff is really just a bonus feature. One day I forgot to charge it during the night and when it took me home on the next day after work it annoyed the hell out of me with the power limitation and still had plenty of charge when I have put it on the charger I don't want to limit myself vaping I want the board to simply cut it off and doesn't allow me annoying myself
  3. I agree Mad but I am talking about Li-Ion that is significantly different AFAIK
  4. I am happy that you think my proposed approach would be a bit more convenient than the present one. However, I don't completely agree with your point regarding to the 3.5V resting threshold for I think that it depends on the load and the batts IR and it can easily be more than just a handful of puffs. E.g.: my batts have ~15% left around 3.5 restV when rest cutoff is set to ~3.25-3.3V (should check the recorded csv and probably will later) this 15% means 28.4Wh x 0.15= 4.26Wh=255.6Wm=15,336Ws=15,336Ws/(25W mean power x 2s mean puff) = 306 puffs for me (if my maths holds And I wouldn't call it insignificant for it is more than 40% of the overall capacity of Evolv's 900mAh reference mod Of course, for Li-Ion it can indeed be a lot smaller should I set my Wattage higher. And that is why I would like to have a bulletproof battery management system that looking after me regardless of my power settings and doesn't cost me precious Whs and/or neither ruins my last Whs if not necessary.
  5. @bmclaurin Thanks to your answers but I really don't get your point even though I happened to hit the record button and checked the result including how the soft cutoff works. Again, it is not for maximize puffs it is for optimize the discharge. Let me give you an example. Example #1 Let the target idle/rest voltage is 3.3V for the sake of battery longevity. Voltage under load is not a real issue as long as it stays above min 2.7V and the battery can recover to 3.3V Let the voltage drop 0.1V for every 50W load (means 0.4 for 200w) just for the sake of the argument. It means that I should set my soft cutoff to 3.2V for 50W, 3.1 for 100W, 3.0 for 150W etc. And if I do it AND stop vaping when I hit the weak battery warning I will get the nice and safe 3.3V rest/idle And that is my point. That I would need different cutoff values for different target drains and would need to stop vaping when hitting the weak battery otherwise I would drain my batteries below target. Or: I set my cutoff to 3.3V and completely ruin my own vape in the 3.4-3.7 idle/rest V range (depending on the power setting) by the soft cutoff regulation. Meanwhile with two values I can set my idle/rest and under load separately fully covering all the wattage (voltage drops) range AND fully eliminate any accidental over drain AND fully eliminate any unnecessary output reduction because the board thinks (wrongly) that my battery is weak: Example #2 Target idle/rest voltage: 3.3V Target min under load voltage: 3.0V Desired operation: If target idle/rest voltage <3.3V no firing at all but low battery warning only If target voltage>3.3V firing as per now protected and limited if needed by the soft cutoff Working in the low volts: As long as I don't hit any of the thresholds the mod would fire as per normal. In this example, below 3.4V idle/rest and above 150W setting I would get weak battery warning and power reduction for the last few puffs which is acceptable. (or if not, I would reduce soft cutoff to 2.9V ) Worst case scenario: V rest/idle: 3.30..01V, power setting 200W and firing. The mod would fire indeed and depending on the batteries even up to 200W more likely below though. Either way, after this very last puff it would cut off nicely and the voltage would recover pretty close to 3.3V Bottom line: Trying to obtain given target rest voltage for Li-Ion with a single under load value (soft cutoff) is not optimal IMO. P.S.: Again, it is not crucial at all. You can save your batteries with the present setting options too. It is all about the quality of the vape when you are getting low on charge without getting the soft cutoff engages unnecessarily.
  6. I don't want to squeeze everithing out. On the contrary. I want to optimize the draw. What this curve is doesn't show is the idle voltage it goes back. You might want to Google a pulse discharge curve. You will find a few. What is interesting in the chart you attached is how it starts. The higher the draw the bigger the initial drop. But if you cut the drain the difference between the idle voltage will be way smaller than the difference between the voltage under load. And that is the point.E.g. in this chart initial drop goes up to cca 0.4V down to 3.8. But if you cut the load after a few sec it would go back above 4 probably pretty close to 4.2.In other word it doesn't mean that you drained your battery to 3.8V. Besides, if you check my battery analyzer settings you would find that my amp draw was around 5A which is not outrageous for a good Li-Ion
  7. I have built and use a 3 x 18650 mod as an ADV and would welcome a Li-Ion Battery option in the battery drop down with 2 different cutoff voltage settings: Cell Soft Cutoff: as it is now, for voltage value under loadCell Hard or Idle Cutoff: for a higher, idle (voltage w/o load) value My understanding is that: Li-Ion has a significant and drain dependent voltage drop (due to its internal resistance?) Under load voltage can go as low as 2.7V as long as the idle voltage goes back to 3V or above. For safety and longevity point of view I would like the board eliminating firing when idle voltage couldn't go back to or above 3.2-3.3V but I wouldn't mind if it goes down to 2.9-3V under load. ATM I can't really do this. If I set the soft cutoff to 3.2 I got weak battery warning (and reduced output) relatively early. If I set the soft cutoff to 3 or 2.9 the board won't prevent me to discharge my batts close to this numbers, would give the weak battery warning though. I admit that it is not some super crucial issue, especially with the 3 x LG HG2 I am using. I get an insane 28.4Wh out of them even if I play it super safe (w/ high soft cutoff settings). But with two values the Li-Ion discharge could be controlled pretty well regardless of the drain and the actual internal resistance without getting the annoying weak battery warning and power reduction unnecessarily. BTW, here is my discharge curve for 3 x LG HG2 3000 mAh batteries @ 50W w 3.09V soft cutoff. LGHG2-3cell@50W 3090mV SCutoff.txt (in txt format for csv is not supported by the page FYI: I have an external quick blow glass fuse in the circuit with unknown resistance therefore my curve is more likely a bit steeper than it should be.
  8. I hope that in the meantime you have found the ideal solution. BTW, I was thinking a simple n channel fet solution with gate attached to the last (first? anyway the one is connected to B-) battery only. Source would be the (-) of this battery and drain would be B- on the board. If I read it right VGS would be + only (and circuit closed there) if the polarity is right and the dV is 3* V bat or there is no dv at all between B- and B+. It sounded promising but I was a bit worried about the extra load attached to 1 cell only and any unbalance it might result. Besides, it would cut off only the main circuit and I don't know if any unwanted potential difference on the charging tab would do any harm even with main ground cut or not. Not to mention that I didn't bother to look into the charging at all Therefore I went for a simple external quick blow fuse and hope for the best
  9. Well, on my wavelength your board didn't read atomizer resistance w/o battery power plug connected and, strictly on this wavelength, kinda think that you couldn't continuously fire the mod up even on 1W settings when only charging cables attached Of course, it is possible that it works if you connect (-) for ground but don't connect (+) (modelling a blown fuse) I might try it one day. I want to hook up an external fuse anyway, so I can check when the replacement board is here (and find room for the extra fuse)
  10. Well, like I have said, my hunting is over. I couldn't get any closer. If Evolv will check/it flex it when they get it back, so be it. But if it wasn't over, I would start from the other side The only thing I can tell for sure that AA can work. So I would look at this function first checking how it can possibly be powered up, which circuit(s) must be closed etc. Than check all the possible bridging ways/spots that can close it w/o fuse) Than check the circuits powered by USB close enough for some mechanical shorting if forced.... etc
  11. I hear you, don't fully agree though I agree that there are too many blown fuses around and I haven't see rock solid evidences on modder failure or on anything else. It could be this or that or whatever. And that is exactly why I pushing on the option that the USB can short out some circuit if forced. It was a very 'lucky' find* and hard to mimic it for testing. I have already stopped experimenting with it as I don't want to deliberately damage neither the board board my cables. But it was a real, live short. The possible outcomes of this short or the actual location of it (on the board or in the male/female socket itself) is still unknown and no one really knowledgeable bothers to look at it. (John just explained normal conditions above that doesn't hold if you short out the designed way) I have actually planned to pushing on until someone checks on all the options, but getting tired. If this is the hidden booby trap (a specific male plug+applied force+preheat power) I know how to avoid it in the future and I will. *For how hard and lucky it was: My mod was opened up, tethered and some atomizer on. As I posted somewhere it was tilted supported by the USB cable and I actually checked the temperature on the board when I accidentally pressed the whole lot and the Atomizer Analyser came to life. At first I thought that I had some contact problem on the back, slowly circling toward the usb But I still don't know if it is actually the USB or not. That is the closest I could get.
  12. It is rmaed. But I still want to know what happened and why to avoid it in the future if possible
  13. Lol You eally get me run hard for my money I like it Helps thinking. In our case it is the potential difference that counts. So lets do a bit of a maths For the sake of simplicity let DC/DC conversion efficiency 100% and there is no voltage drop in the system. Let: Ppp(preheat power)=200W R(load, i.e atomizer)=0.2ohms Then Vload(atty)=sqrt(200W*0.2ohms)=6.32455 Iload(atty)=sqrt(Ppp/R)=31.623A and Vout(from DC/DC converter)=V(load)=sqrt(200W*0.2ohms)=6.32455 Iout=Ppp/Vout (from DC/DC converter)=I(load)=sqrt(Ppp/R)=31.623A Vin(battery)= 11.1V Iin(battery)= depends as per below Now the scenarios. 1., Normal usage: Ppp=Vload*iload=Vout*Iout=Vin*Iin=200W -> Iin(battery drain)=200/11.1=18.02A So far so good, we are safe) 2., USB shorted out and the shorting current is working against batteries due to the potential difference Let Vusb=4.77545V<5V (for the sake of simplicity) Now, to get the required potential difference on the load you will need higher Voltage: DV=Vload=Vout-Vusb=6.32455V -> Vout=6.32455+4.77545V=11.1V Iload=Iout=31.623A* Now Ppp=200W<Pout=Vout*Iout=Vin*Iin=351.0153W And Iout=Iin=31.623A (battery drain)* And Kaboom So, it looks feasible *for the sake of simplicity. Probably different, depending on the additional resistance in the system that I don't know, but I beleive that in general, the maths holds
  14. Thanks for that Don't flex the cable/pry the socket then! Because that is what I have feared that it shouldn't. And I still can get it work which is a bad news because it means I can short something out. OMG
  15. I am applying T=F x l rotating torque on the socket using the plug as a lever as I described above This unfortunate move can be described as flexing or rotating or moving upward or prying or whatever. But this is it: To rule out the option that an upward torque of given magnitude applied on the socket causes the problem we got a very simple solution: Please confirm that a fully functional board tethered via a fully functional USB can and always should read resistance via Atomizer Analyzer when the fuse is blown. If this is the case, than it is my cable(s). If not, it is the socket. There are no more options.
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