Tag Archives: tcr

Curves Are In Baby !!

escribe downloads

Escribe Battery Curves, TFR / TCR Curves and Mod Thermals Downloads

Curves are in baby!!

That’s right. Our awesome downloads section just got even more awesome.

We’ve created three brand new sections which are going to be fantastically useful. You’ll now find dedicated areas for TCR/ TFR Curves, Mod Thermals and Battery Discharge Curve CSVs. All in one easy to navigate place.

We want people to have the best possible experience when using our wire. By doing this we’re giving you the tools to achieve the best results when using a DNA mod in temperature control.

So what exactly are these mystical curvy things? 

Read on and we shall explain below.

TFR/ TCR Curves.

A TCR Curve (Temperature Co-efficient of Resistance) is a plotted chart depicting mathematical rises in a material’s resistance coefficient of the material’s temperature. For example, a Ni200 coil when heated will rise in resistance quite markedly. This rise can be predicted at a given temperature using whizzy maths, and a temperature controlled capable board will be able to use this information to maintain a temperature at the coil and prevent dry hits. It is the basis of all temperature control vaping. Props to Evolv for coming up with that sorcery.

A TFR (Temperature Factor of Resistance) is similar to TCR, but is based on actual observed measurements rather than pure mathematics. We built a complicated and probably quite dangerous rig and measured the TFR of our wire, giving us accurate real-life TFR data. Lars from Steam Engine (a genius and a gentleman) then used this data and translated it into downloadable CSV format to be used with DNA devices. We want people to have the best possible experience when using our wire. By doing this we’re giving you the tools to achieve the best results.

All our TFR/ TCR files can be found int the “Wire TFR Files” section of the downloads page here.

If you want to find out how we got our results, read our blog post on it here

Mod thermals

In order for Temperature Control and Replay to perform as accurately, efficiently and effectively as possible, the board needs to know the parameters in which it is calculating. The marvellous mind of the DNA constantly analyses, calibrates and controls a multitude of variables, and in doing so needs to understand it’s operating environment. The temperature sensor is situated on the board, so the DNA uses data collected from case analysis to accurately predict room temperature and the starting temperature of the coil. It does this by a real room temperature measurement being entered at the beginning of case analysis and then monitors board temperature during charging to understand how the internal mod temperature relates to the actual room temperature. Put simply, the board more accurately determines the starting temperature of the coil with this information.The information from TFR/ TCR curves can then be applied, using the case analysis data as the starting temperature point. This allows for greater accuracy in temperature.control and gives you the best vaping experience possible.

In this section of the Downloads facility we present you with Mod Case Thermal data for our devices. Feel free to download and use them according to your will.

Battery Discharge Curves.

 

Escribe has a function called “Battery Analyser” which allows you to run a cell discharge cycle according to cell cut-offs and various output wattages (the most common being 40 watts). The analyser carefully plots the voltage decrease as the cell is drained and generates data that can be outputted in .csv format. These curves can then be uploaded to your device to ensure the board is monitoring and reading the current state of your cell correctly whilst you are using it. Whilst this won’t magically add another 10,000 mAh to your battery, it will calibrate the monitoring and information display accurately according to the cells you are using. This way both you and the mod will know exactly the state of your cell and avoid any erroneous readings. 40% remaining  will be 40% usable charge and you won’t get diddled thinking it’s higher. 

We have a wide selection of curves available for many popularly used cells. We have csv data for single cells, 2S and 3S configurations. We shall add many more as they become available. Special thanks goes to Michael Schmidt for providing us with much data taken from his site dna200.de. We also offer up many curves generated by us using a resistor bank made up of two 200w 0.1ohm power resistors in series ,mounted onto an aluminium heatsink to disburse heat  We are running more tests and will be updating the site with curves regularly.

 

So where can we get these sexy curves?

Easy!

 In the Downloads section here.

 At Stealthvape we like to keep it simple, and are on a mission to make mod making as easy as possible. As well as providing you with the best, highest quality mod parts and materials, we believe in giving you more. We will be constantly updating the site with useful new info. Be sure to follow us on social media  for more upcoming handy new features.  Please like, share and comment on our posts and let us know what you’d like to see on the site.

If you have any files you’d like to share here, please get in touch and we’ll be happy to share them amongst the community.

 

 

TFR CSV Files For Our Wires

 

What is TFR or Temperature Factor of Resistance?

Some materials may not follow a linear TCR completely accurately, so a TFR is based on observed resistance changes at a series of set temperatures that often follow a slight curve instead.

Here’s an exaggerated image showing the difference.

You can see the difference between a linear TCR and a TFR curve.

So why are you telling us this?

Well, being boffins, we created individual precise TFR’s for our Stealthvape wires that are suitable for use in temperature control. We built a very accurate PID controlled hotplate and monitored resistance changes in various coils suspended in a bath of silicone oil.

We used a platinum PT100 temperature sensor and also 2 k-type themocouples and recorded temperatures from -17c to 0c and from 25c to 300c in 25c increments.

Lars from the mighty Steam Engine helped us use that information to create unique CSV’s for Evolv DNA boards which can be uploaded to devices using Escribe . These CSV’s for temperature control are available below.

You can find the following wire profiles in our download section

316L

NiFe30

Ni200

If using a mod that doesn’t accept TFR’s, you can often enter the TCR manually. Different mods sometimes expect a slightly different format.

Sometimes Ni200, for example, is usually 6000 but needs to be entered as 600, or 0006.

Based on the TFR test results, we’d suggest using the following values depending on the format the mod is expecting:

NifFe30 : 4920 or 492

316L : 883 or 88

Ni200 : 6230 or 623

Wires like Kanthal A1 and Nichrome 80 / Ni80 have a very low TCR, so don’t work in temperature control mode. Evolv DNA250C boards are able to use the Replay feature with Nichrome coils (with varying degree of sucess) by activating the “Allow on Dubious Coils” setting in Escribe. We won’t however be including Nichrome or Kanthal wires in our TFR measurements.