Dampmaskin

I think you need an infrared thermometer, a thermocouple or a resistance thermometer for that. If the "Mod resistance" value in EScribe is correctly set, and the coil material that you're using is according to specifications, I believe the temperature reading of the DNA 200 should be accurate.

Maybe at least get rid of [b]---F[/b] when using Kanhtal. Every time the DNA200 tells me ---F, for a tiny moment i am compelled to think*. It clutters up the screen, while adding little of value (nothing that I can see). IMHO, it would be equally informative to keep that part of the screen blank when not in TC mode. That is, unless the "one screen setup per profile" feature requested by StirCwazy is implemented. If it is, this post will be moot. *) The fact that I normally adjust my temperatures in °C probably doesn't help.

A numerical input would be sweet, so that we could set the max voltage to whatever we wanted. Of course either limited to sane values, or with warnings if you go too high or unreasonably low.

1) Are you using the TCR calculator (defaults to generating 7 point curves) or the Wire Wizard (defaults to generating 8 point curves)? AFAIU, the DNA200 can support 8x8 temperature points, in other words you should be able to use all 8 profiles with 8 temperature points in each profile. Are you running the newest software and firmware? See this thread for the newest versions. 2) I believe that may be a limitation in EScribe that should and probably will be fixed at some point. But I'm not sure if that you can get a decent temperature reading with a TCR that low anyway. 3) Sounds like your temperature curve or TCR value may be off. Or maybe your mod has some significant resistance. Have you measured it and entered it into EScribe? See this thread.

The a new calculator that makes it easier to get TCR profiles for mixed builds hos been "officially" released. I think it may be time to add the link to the link page between EScribe and Steam Engine. https://my.evolvapor.com/info/materials The old calculator will still be available, so removing that link is entirely optional.

I've had a perhaps related issue. When building a TC coil with a lower TCR than Ni200, and boosting the preheat to 200W and "Hard", the DNA 200 seemed to pop out of temp control. The temperature curve disappeared from Device Monitor, but I could still see the resistance increase as usual during the puff. I couldn't regain temperature control - and the temperature curve in Device Monitor - until I lowered the preheat. The wire was 30ga Kanthal A1 twisted with 30ga Ni200. Something like this: [CODE]"Temperature (degF)","Electrical Resistivity" -94,0.6509078891945742 68,1 212,1.3261584754547935 572,2.4572348525753145 662,2.7121364826264474 752,2.938747849424949 842,3.160562053313862 932,3.375997699618637 [/CODE]

I'm thinking there must be something wrong with either the wiring or the board. Three different batteries don't just fail in the exact same way by chance.

Aha. That explains everything. I changed it to 200W and uploaded, so hopefully I'll be able to fire Kanthal builds at whatever power I want to from now on. I find it a bit strange that the DNA still showed 130W when it limited the power to 100W, and to be honest the limit seems maybe a little bit arbitrary, but at least now I know the explanation. Thank you! (I think you're right about the tank BTW.)

I was at a vape meet, and tried a tank that was supposed to be good at 130 W. So I set the mod to my Kanthal profile, adjusted the watts to 130, and had a vape. The DNA flashed "Kanthal max power" at me. The wattage in the display still said 130W, so there was no indication that it was throttled in any way. The vape was fine, but the owner of the tank said it felt more like 100W. I tried googling DNA 200 "Kanthal max power" but no luck. I checked out the datasheet, but there was no description of the error codes. So my question is: What exactly does "Kanthal max power" mean? Is there a list of the error codes and their meanings somewhere? My battery was a little less than half full. I don't remember the resistance of the tank, but I think it was less than 0.4 Ohm - although I wouldn't swear on it at this point.

Yeah giving people the ability to go bananas was a big part of why I decided to make it that way. But a fair warning; When you reach three or more levels of wires-within-wires, accuracy is probably not going to be stellar. I suspect that errors will accumulate and multiply, and what have you. That is correct. Wire length doesn't do much useful right now, except give you the resistance. I will add a coil wrap counter at some point, or give the user the option to select inner diameter and wrap count, and have the wire length calculated from that.

After a year of pondering, a month or two of planning and gathering gumption, and a few days (weeks?) of sweating and cursing over a computer keyboard, I have finally come up with another coil calculator (or rather, a wire calculator this time). This is for TC coils, and also for all the fancy schmancy coil freaks out there. With some luck and some time, it can grow into a calculator for most coil winding needs. Who knows? I haven't linked to it from the Steam Engine navigation menu yet, because I don't want everyone and their grandmother using it right now. It is not a finished product. But it has reached a point where I feel it's time for some feedback, lest I go astray and turn it into a steaming (vaping) heap of garbage, so here is the sooper sekrit link for you: Wire Wizard Feel free to check it out, take everything with a grain of salt, and if you don't understand the first thing click "How it works". Then enjoy whatever works, try to enjoy whatever doesn't, and also feel free to say exactly what you think below.

I agree, this would be an awesome feature to have. Separate screen setups per profile would also allow the user to set up two profiles for the same coil, with different displays, if they wanted that.

I'm guessing this is why. What I would like to see, was a percentage instead of a fixed preheat wattage. So e.g. with a setting of 300%, when you're vaping at 10W, the preheat is at 30W, and when you're vaping at 50W, the preheat is 150W.

I've recently learned about a new Chinese mod that claims to do TC with Kanthal. Of course it's probably not real TC, and it's not achieved by reading the changes in resistance. There are several "theories" floating about the net, about how this is achieved. One theory is that it uses PWM, and that it measures changes in reactance as the Kanthal heats up.Another theory is that it does not do TC at all with Kanthal, but some sort of dry coil detection: When the juice dries out, the resistance of the coil/wick system increases, because the juice itself has some conductivity.This got me pondering, and now to my questions: Does the DNA 200 have enough memory and CPU power to implement completely and radically new features and modes in future firmware versions? (I'm guessing yes plenty.)Is measuring juice saturation even doable in any reliable way?If a good reason to use PWM appears somewhere along the road, will the DNA 200 hardware support it at all, and if so, how well, and what kind of switching frequencies are we talking?As the title suggests, I only ask this out of curiosity, and I don't expect much precision in the answers. It's more about what the DNA 200 in principle can do, or not. I've come to understand that it's designed to be flexible, and firmware upgradability opens up a whole new world of forward compatibility, but just how far can the hardware be stretched?

Yes, once again Microsoft Internet Explorer decides to behave differently from all the other browsers out there. I have updated the "How it works" text with a warning, the workaround, and some links to read more. I may be able to find a way to do it in MSIE some time in the future, but it's not my top priority right now. In the meantime, use a better browser (any other browser), or use the workaround.

Which browser and operating system are you using? As a workaround, you can manually make a cvs file on your computer, copy the content of the "DNA 200 output" field to the clipboard, and paste it into the file.

I think some mods do it dynamically, which I like. So something like this would be nice: <15 W: 0.1 W increments. 15-30 W: 0.5 W increments. 30-60 W: 1 W increments. 60-120 W: 2 W increments. >120 W: 5 W increments.

Yes, as long as you use no more than one single coil material, the TCR curve for that material will always be the same, regardless of how you clapton, twist or wrap it, and regardless of the resistance of the coil.

If the resistances differ by a lot, you can get away with using only the lower resistance. Using both will always be more accurate. You can find a tutorial about it here if you're interested in learning more.

For now you will have to go to the coil calculator, select the material and gauge, guess a resistance, and look at the resulting resistance wire length. If too high/low, adjust the resistance accordingly, and check again. Repeat until you're "close enough". I'm planning a brand new calculator that will make all this a whole lot easier, but it's an ambitious project that will take some time.

For the best accuracy, you should enter all wires used. For claptons you can approximate the length of the outer wire by doing the following: (radius of center wire + diameter of outer wire) * pi * 2 * length of inner wire / diameter of outer wire. (I haven't tested this formula, so double check it before you trust it 100%) But it if it correct, you can then use the coil calculator to jog the resistance around until you hit the length of each wire. Enter these resistances in the TCR calculator for both coil materials, and you should get a pretty decent temp curve. Twisted is simpler: Just find the resistance of both wires (again you can use the coil calculator for this, as long as you know the lengths), and enter both resistances in the TCR calc.

[Outdated info in grey:] Oh, right. The reason for this is that when you query a temperature below the lowest temperature in the curve stored with the coil material in Steam Engine, it returns the factor for the lowest available temperature (in other words, a flat curve). The same thing happens if you query a temperature above the highest temp. I'll update the curves for 316L and 317L with some additional temp points. Maybe implement some extrapolation as well, in order to return better factors for out-of-bounds temperatures. In the mean time, lowering the lowest temp factor(s), and/or increasing the highest one(s) by a tiny amount should do the trick, as you've discovered. Alternatively, you can just remove the out-of-bounds temperature point(s) from the first box in the TCR calculator altogether. This is probably the cleanest solution, and the easiest one as well. Edit to add: I have improved the TFR curve for 316L and added one for Ti1. I could not find a good curve for 317L, so that one is still using a linear TCR. I also added extrapolation for edge cases, though I don't believe it will be used much from now on.

Monoxxide, you're exactly right. If you twist a 0.1 ohm Ni200 wire and a 1 ohm Kanthal wire of the same length, you can select both materials in the calculator, and change the resistance for the Ni200 one to 0.1 ohm. The calculator will then give you the temperature to resistance curve for that combination of wires, plus a "sensitivity" percentage value that will give you a hint about how accurate your temp control will be with this particular coil.