Temp Control Masters!!!! Please Help!!! NiFe52 Question

[xlolzix]

First of all, I just want to say thank you to everyone here for helping out and creating this humongous base of knowledge. this is my first post, but I am glad to be a part of the Evolv community =] My question is for all the TC Guru's out there. I am wondering how to calculate the Temperature coefficient to just the number such as "0.0004" for example, I received some NiFe52 and loaded 2 .CSV profiles from WireWizard. The wire MFG that made this NiFe52 wire provides the below information for the Temperature Coefficient. I googled all over, but can not figure out how to turn that equation into the Temperature Coefficient number. I find using the Coefficient a more satisfying vape and I would absolutely love to have the NiFe52 vape using that. If anybody knows how to find out what the Coefficient is, I would love you! I posted a link for the wire as well if there is any more info needed but this should be all of it. Thanks in advance!



Technical Specification:

Ohms/m - 2.19

Chemical composition
Name Main Composition (%)
Fe - 45-47 
Si - <0.5 
Ni - 52-53
Mn - <0.05 

Temp. Coeff. Of Resistance ( a X10-6/°C) 20 °C - 3400

http://www.wireandstuff.co.uk/products/0.5mm--500-Micron---24-AWG-----NiFe52-Wire----416.html#SID=109

[VapingBad]

It is found by measuring or looking up the value, I don't think it can be predicted by chemical composition and the easiest way is to use a value that someone else has had success with. 

SteamEngine have NiFe52 as 0.004036, but the CSV would be even better http://www.steam-engine.org/wirewiz.asp#


But you can measure it:

Evolv have posted that you can get really accurate results putting a section of the wire you want to test in a pan of synthetic oil, heating it with a good thermometer and measuring the resistance.  You would need all the wire to be in the oil, so solder thick kanthal legs between it and your ohm metre and be careful you stay below the oil's flame point.   You could also start with an educated guess and do a cotton scorch test over a range of temps, say 400 F - 600 F in 20 F steps, keeping a consistent fire time, 10 seconds is good and you can trigger that with device monitor or the serial terminal. You will get a graduated set of brown strips on the cotton and if you do the same with a similar size coil using Ni200 it is easy to line them up and see if you need to go higher or lower with your TCR.

The TCR is the proportion (0-1) of how the resistance cahnges with one degree Kelvin or Celsius in temperature.

[dwcraig1]

The suggested 3400 would be 0.0034

[xlolzix]

So for "( a X10-6/°C) 20 °C - 3400" that equates to adding 0.0034 into Escribe for the NiFe52 material?? Thanks either way!!!!

[VapingBad]

x10-6 means move the decimal place 6 times to the left so 3400 -> 0.003400, normally the -6 would be superscript/small text level with the top of the main text, electronic calculators often use E-6 fro the same thing.

[xlolzix]

Thank you guys so much.  Case closed =]

I have already messed around with the Steam Engine .CSV for my wire, but want to try just the coefficient. I will try 0.003400 as the MFG suggests, and then I will try the 0.004036 as SteamEngine suggests for NiFe52.

Thanks again guys, appreciate the help.

[dwcraig1]

I have NiFe 48 from here: https://www.zivipf.com/epages/63862298.sf/en_GB/?ObjectPath=/Shops/63862298/Products/NiFe48-0.50/SubProducts/NF48-0.50-10m
They list TCR as 400, also it's 52% Ni but they call it "48". Crazy wire has both 48 and 52, I'm "interested" with your results.

[Spector NS5 RD]

i have a spool of 24 and 26 awg nife48 from zivipf.com as well. i like it because you can glow your coils and not have to worry about nasty oxides like Ti produce when heATED.