What's the formula to calculate temp based on last seen, high resistance on the D2?
IPV D2 announced.
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What's the formula to calculate temp based on last seen, high resistance on the D2?
You'd need to know the TCR of the wire you were using, and of course, the base resistance.
Its not the fact that it shows Rmax. That is great for all the above reasons. But you need a solid press of the fire button to see the locked resistance. That is rubbish for two reasons
1. Its not intuitive at all
2. It means that you are probably applying a short pulse to the coil so the base/locked resistance is not, in theory, accessible.
The whole idea is just clumsy I guess and as @Croak said, a lot of confusion could have been easily avoided. I mean it had Mike Vapes fooled...
Base (locked) resistance
TCR of Ti = .0038
TCR of Ni = .006
So let's say you have a .2Ω Ti coil set to 450°F (232°C). Let's assume room temp is 68°F (20°C).
First you need to find out how much the temperature of a (room temp) coil changes when it hits your max temp. In this case:
232C-20C = 212°C
So, your coil will make a 212C change in temp to get you to 232°C (450°F).
Next, you take the base resistance and multiply it by the TCR for that wire:
0.2Ω * .0038 = .00076
This means for every 1°C increase in temp, the resistance will rise by .00076. Since we know that the temperature is supposed to change 212°, then we simply multiply it:
.00076 * 212 = .161Ω
This means that your .2 coil should in fact increase by .161Ω in order to hit 450F (232°C).
The last step is simple. Take your base resistance and add the change in resistance to it:
0.2Ω + 0.161Ω = .361
So, your coil should be .361Ω when firing it. If it reads significantly off of this value, then you know something is wrong somewhere.
Has anyone tried the new vertical coils on the subtank mini? I'm just about fed up with the damn rba deck for this thing and about to throw it out the window. How is the coil life on them. The original coils would only last me a few days?
there arent any TC (ie Ni200) bversions yet that I can find. Havent tried the kanthals..
Whats the problem with the RBA deck?? I have never had a problem with the v1 or the v2 versions! Can I help maybe??
I was just going by the spec sheets listed by some industrial sources like this. But that's probably for theoretically pure Ti. Even our CP Grade 1 isn't 100% pure, so its TCR might differ slightly.
The long, full blown, Spanish version of the mathematics behind the TC calculations.....
Sorry, I didn't have enough time for a translation, and Spanish is my first language, but I can cut to the chase, in short, directly translated:
If you got enough data about resistance or resistivity variation with temperature, you can plot those points or you can try to be close to the actual data with some mathematical approximation. The simplest one is a linear regression of the data. Even simpler, and often enough to get the work done, what mathematicians called a local aproximation based on first derivative, as linear function. Enough chit-chat, let's put it plain. You get close to the actual data with this:
Where R0 is the base resistance (the fixed one with the + and - buttons on YiHi boards, or recently read after confirming the 'new coil' question on Evolv boards). That one is measured at T0 temperature, which is postulated as 20 ºC (68 ºF). Of course, R is the actual resistance as it get higher because the temperature rises. B is the local slope of the representation in the rearranged formula:
which renders (or it should) a straight line which passes through the origin (0,0). That number, which has units of inverted temperature, is the famous TCR.
I read the former message about the process and I didn't get convinced about it. Something was off, but I could get mesmerized by the explanation. If you can work with this (relatively simple) equations, is not some big piece of cake. Some examples from my own numbers:
* With actual resistivity values found in the Net, my linear correlation of the above renders B=0,00575 1/ºC instead the 0,0060 or 0,0062 values often found, but the purity of nickel is of paramount importance to fine tuning this.
* This is how it appears in a plot, using just the four points relevant to our application (from 20 through 300 ºC):
* Once you get the gist of the above formulae, you might ask for the final useful one:
, which is just a new reordering of terms..... and with actual values:
with a base resistance of 0,081 Ω and a maximum temperature set (by user, in the mod) at 210 ºC, using that nickel TCR obtained as B=0,00575 1/ºC, the maximum resistance that the mod should show is about 0,17 Ω.
Bear in mind that we are getting values with not so many significant figures (just two, in fact, with the former numbers), that is, the truncation in calculations and error bars are pretty high, and that each TC controlled PCB has its own algorithms to push the brakes (that is, lowering the voltages applied) as the temperature approaches near the maximum value, so you do not get exact figures and nail the expected numbers. When a reviewer has got actual temperature values (with a thermocouple probe or another methods), like the ones that Phil Busardo and Dirk Oberhaus have recently done, usually you see how the mod approaches the target, but the final 20 - 30 degrees are not immediately obtained, to avoid to get beyond the target.
oW! I know it, I should look for atonement after this one........imagine the original, full blown one!....
Sorry, I didn't have enough time for a translation, and Spanish is my first language, but I can cut to the chase, in short, directly translated:
If you got enough data about resistance or resistivity variation with temperature, you can plot those points or you can try to be close to the actual data with some mathematical approximation. The simplest one is a linear regression of the data. Even simpler, and often enough to get the work done, what mathematicians called a local aproximation based on first derivative, as linear function. Enough chit-chat, let's put it plain. You get close to the actual data with this:
Where R0 is the base resistance (the fixed one with the + and - buttons on YiHi boards, or recently read after confirming the 'new coil' question on Evolv boards). That one is measured at T0 temperature, which is postulated as 20 ºC (68 ºF). Of course, R is the actual resistance as it get higher because the temperature rises. B is the local slope of the representation in the rearranged formula:
which renders (or it should) a straight line which passes through the origin (0,0). That number, which has units of inverted temperature, is the famous TCR.
I read the former message about the process and I didn't get convinced about it. Something was off, but I could get mesmerized by the explanation. If you can work with this (relatively simple) equations, is not some big piece of cake. Some examples from my own numbers:
* With actual resistivity values found in the Net, my linear correlation of the above renders B=0,00575 1/ºC instead the 0,0060 or 0,0062 values often found, but the purity of nickel is of paramount importance to fine tuning this.
* This is how it appears in a plot, using just the four points relevant to our application (from 20 through 300 ºC):
* Once you get the gist of the above formulae, you might ask for the final useful one:
with a base resistance of 0,081 Ω and a maximum temperature set (by user, in the mod) at 210 ºC, using that nickel TCR obtained as B=0,00575 1/ºC, the maximum resistance that the mod should show is about 0,17 Ω.
Bear in mind that we are getting values with not so many significant figures (just two, in fact, with the former numbers), that is, the truncation in calculations and error bars are pretty high, and that each TC controlled PCB has its own algorithms to push the brakes (that is, lowering the voltages applied) as the temperature approaches near the maximum value, so you do not get exact figures and nail the expected numbers. When a reviewer has got actual temperature values (with a thermocouple probe or another methods), like the ones that Phil Busardo and Dirk Oberhaus have recently done, usually you see how the mod approaches the target, but the final 20 - 30 degrees are not immediately obtained, to avoid to get beyond the target.
oW! I know it, I should look for atonement after this one........imagine the original, full blown one!....
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Good luck with that......
Performing just a comparison between grades 1 and 2, and it goes from 52 to 56 μΩ.cm......and that's just at 'room temperature', which, depending of the source, could be 15, 20 or 25 ºC......
Some old curves, easily found just googling them....
Courtesy of Google books....... I'll pick up the first table (we should start with something, shouldn't we?) and see what happens:
0,0047 in these numbers.....let's take the other ones!......
That's with grade 2...... 0,0038....
and I could be droning on and on for hours....just as many as raw data you get me!
The physical properties for these alloys are really tricky!
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Sorry, in my first reading I did not catch up all this properly. It's a step by step development of:
which, in the titanium example, would render:
and it's the same, of course, that example nails the correct answer. It's up to you to choose the easiest way....
Sorry, in my first reading I did not catch up all this properly. It's a step by step development of:
which, in the titanium example, would render:
and it's the same, of course, that example nails the correct answer. It's up to you to choose the easiest way....
My example was just something I came up with that worked for my brain.
Good luck with that......
Performing just a comparison between grades 1 and 2, and it goes from 52 to 56 μΩ.cm......and that's just at 'room temperature', which, depending of the source, could be 15, 20 or 25 ºC......
Some old curves, easily found just googling them....
Courtesy of Google books....... I'll pick up the first table (we should start with something, shouldn't we?) and see what happens:
0,0047 in these numbers.....let's take the other ones!......
That's with grade 2...... 0,0038....
and I could be droning on and on for hours....just as many as raw data you get me!
The physical properties for these alloys are really tricky!
Yes, quite a variance. I think what is going to have to happen is vendors of wire are going to have to do their own testing (with a thermocouple) and provide us with the proper TCR for their wire in the vaping range. It only needs to be accurate between 300-600°F.
Based on my very rudimentary testing, i am convinced my IPV D2 has its TCR for Ti set to .0038, which seems to make it read lower than it should. A TCR of .0047 would make it really far off the real temp. For the wire I am using (Unkamen), .0035 seems to be more in range of reality.
I've just recently started to use both Ni-200 and Ti-Gr.1 wires. And the second ones are from what someone could name as a not so reliable vendor (Fasttech). But.....
Wire diameter and wicking material have also something to add, in the form of heating inertias. When I use thinner wires, it seems to ask for lower cutoff temperatures (lower inertia to heating). That's even clearer if I wick over silica (the Kanger Aerotanks and Ni-200 work like a charm, but a lower temperature settings, and of course minimal "Joule" settings), which I presume is due to the inferior drain you get over fiber-glass wicks. Coupling both effects the rise of temperature overwhelms the algorithms of the chip and the final result is a lower temperature setting.
Anyway, comparing 0,40 mm Ni-200 and AWG28 (0,32 mm) Ti-Gr.1 (allegedly), my IPV D2 seems to ask for higher temperature settings in titanium. Not big ones, but here they are, about 20 ºC. Due to being the titanium wire slightly thinner, that's something (or just a not-so-grade-one titanium, too early to know for sure....).
It is a subjective impression, and I could be totally wrong for that matter......
Wire diameter and wicking material have also something to add, in the form of heating inertias. When I use thinner wires, it seems to ask for lower cutoff temperatures (lower inertia to heating). That's even clearer if I wick over silica (the Kanger Aerotanks and Ni-200 work like a charm, but a lower temperature settings, and of course minimal "Joule" settings), which I presume is due to the inferior drain you get over fiber-glass wicks. Coupling both effects the rise of temperature overwhelms the algorithms of the chip and the final result is a lower temperature setting.
Anyway, comparing 0,40 mm Ni-200 and AWG28 (0,32 mm) Ti-Gr.1 (allegedly), my IPV D2 seems to ask for higher temperature settings in titanium. Not big ones, but here they are, about 20 ºC. Due to being the titanium wire slightly thinner, that's something (or just a not-so-grade-one titanium, too early to know for sure....).
It is a subjective impression, and I could be totally wrong for that matter......
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I do like it. But I cant get past the c0ck ring for airflow adjustment. This did make it small and generous liquid capacity, but its pretty janky. I gotta go with the Cthulhu V2, it has all the options that I want. I ordered one a couple minutes ago from Smog Distro they have 9 left in stock.You looked at the Steamcrave Aromamizer V2, with the optional Velocity-style deck? Don't like the rubber airflow control ring, but I do like the direct airflow to the coils, RDA style, combined with the Velocity deck option.
Aromamizer OCC Tank 6ml,AROMAMIZER TANK,,steamcrave
I just tried to use temp mode on a kanthal build. I've put max temperature, locked the resistance and just started vaping on the same joules as watts that i use in power mode. I know that i won't have temp control with this but the weird thing is that i like more than power mode. It is a lot smoother and the taste is better.
Depending on your atomizer resistance and how you calibrate the cold/room temperature one, as if you were in TC mode, you'll set some sort of braking system for heating. Of course, non-calibrated (no idea about the real temperature of braking, as kanthal has an absolutely plain resistivity curve), but some broken brakes, after all.....
.... and, as a consequence of using prior hardware (SX130, with only step-up voltages in pure DC mode, but simulated step-down in PWM mode, and that was user selectable), now SX130 H uses the user selectable PWM mode coupled with the logics to sense and use the temperature (as resistance of the coil, or the voltage needed to maintain power) as a full-fledged temperature control.
Neat, huh? Ultimately, if you use "Joule Mode" you're using PWM output and simulated step-down, so with atomizers with less than 1,6 ohm, which suffer of the lack of real regulation for low wattages in 'Power Mode', you have some regulation (down to 10 W). If you try this with a 0,5 ohm coil, the difference would be like night and day. At 3,6 minimum voltage in 'Power Mode', you cannot run that coil at less than 25 W, despite the screen setting, but in 'Joule Mode' you can go down to 10 W. Oberhaus' measurements show that, as a matter of fact, it does not go at 3,6 V if you set a low wattage, instead it goes down at even about two and a half volts, unsteady output, a bit less, but....
I'd rather like to set the proper coil to get those low wattages. It's common sense and basic vaping recipe.....
What's better than an IPV D2?...two of them of course. Got my silver version today. It included a case this time (in white) - although I have a transparent one in transit but probably won't use either one of them very often. The buttons seem slightly easier to press compared to my black one but it's nearly unnoticeable.
I'm not sure if it's been discussed but the firmware has been upgraded to V3 (SX130H V3.0), and from what I've noticed so far the ohms no longer show real-time fluctuations...it stays at the locked-in resistance. I've been using it for only a couple of hours and haven't noticed any other changes at this time...same great vape.
So here's some vape porn...topped with my EHPro Lil Boy RDA:
I'm not sure if it's been discussed but the firmware has been upgraded to V3 (SX130H V3.0), and from what I've noticed so far the ohms no longer show real-time fluctuations...it stays at the locked-in resistance. I've been using it for only a couple of hours and haven't noticed any other changes at this time...same great vape.
So here's some vape porn...topped with my EHPro Lil Boy RDA:
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