Wattage benefit on DNA

[FnZ]

Hi all,

I recently buy my first dna device (dna75) and I'm joking a little bit with escribe.

Nice tool and lots of stuff on it to enjoy

I have a question regarding wire materials and their sense to be charged on DNA: 

Some wires cannot be used in TC mode so I don't understand the reason why they can be uploaded on board.

For example kanthal or ni80 can be imported as material on the box chip but cannot be used in TC mode. 

The question : what are the benefit usign a dna chip in wattage mode using the appropriate profile in which select the right material?

 

[Wayneo]

5 hours ago, FnZ said:

The question : what are the benefit usign a dna chip in wattage mode using the appropriate profile in which select the right material?

Original wire profiles from steam-engine .......... none officially, but you can set and see that 'word' as one of your small display options.

[FnZ]

4 ore fa, Wayneo ha scritto:

Original wire profiles from steam-engine .......... none officially, but you can set and see that 'word' as one of your small display options.

mmmmm tnks for the replay  

do u mean it's just steam engine and not evolve to pubblish them?

[giz_60]

Kanthal & Ni80 wire is NOT a TC compatible wire...therefore, they cannot be used in TC mode...

[FnZ]

12 ore fa, giz_60 ha scritto:

Kanthal & Ni80 wire is NOT a TC compatible wire...therefore, they cannot be used in TC mode...

HI @giz_60 , you are right of course and this is the reason why I don't understand the meaning and utility to have wire tcr curve for that to charge on escribe.Does it mean that using in wattage have some benefit having the right wire charged on box?

[awsum140]

I think the right question would be why load a non-TC mode wire profile on a TC device in the first place?  Power mode, non-TC, is the same no matter what wire is used and the only adjustment available is the power level.  Temperature, and therefor a TCR, are not factors and can't be controlled.

[FnZ]

Hi @awsum140 , thanks for reply. I agree but the dubt start using steam-engine and reading instruction on "wire wizard page" :

TCR

If you want to download the TCR profile as a CSV file to your DNA 200, click the DNA200 tab. This function is only available if all your selected materials have an associated TFR/TCR profile. Materials that lack a TFR/TCR profile are marked with an asterisk in the dropdown menu.     

                                                                       

      Looking on the wire drop down menù I saw that kanthal and ni80 have a tcr profile....          

 

So, it make no sense starting from consolidated point KA1 and Ni80 cannot be used in TC mode....It makes me a little be confused 

 

 

Edited September 5, 2017 by FnZ

[giz_60]

Most any wire you apply an electrical current to is going to warm up, therefore most DO have a TCR value applied to them. However, doesn't mean that they will work in TC mode. Because the TCR value of Kanthal & Ni80 is so low, they will not work in TC mode.

[Wayneo]

@FnZ According to Evolv, their chips need a material with minimum coefficient of 0.0008 in order to control it in TC. See that second value in the blue box (TC Precision) with a value of 5 .......... that means it's almost impossible (higher values are better).

If your question is more related to steam-engine wording you might pose that question to them

[FnZ]

4 minuti fa, Wayneo ha scritto:

@FnZ According to Evolv, their chips need a material with minimum coefficient of 0.0008 in order to control it in TC. See that second value in the blue box (TC Precision) with a value of 5 .......... that means it's almost impossible (higher values are better).

If your question is more related to steam-engine wording you might pose that question to them

many thanks for your reply. it makes me clearness  

[James]

In EScribe, the "Temperature Coefficient of Resistance (approximate)" option has a minimum TCR that it allows to be specified. This is essentially an editorial decision on my part -- below a certain level, it's just not going to work well. The firmware of DNAs has no such restrictions, so you are welcome to upload any monotonic curve, and it will happily *attempt* to control to it. It will try.

 

As an aside, here are a few reasons that controlling very low TCR can't work well:

The smaller the resistance change, the more other parts of the system will distort the accuracy of the result. For example, some stainless steel atomizers have nickel legs. Suppose the nickel legs heat 20F. If the legs are a tenth of the resistance, stainless has 1/6th the TCR of nickel, so that's going to measure as if the stainless steel has increased 20F*(6/10)=12F. So as the legs heat up, your vape gets 12F colder, even though the coil is staying the same. Suppose the material you chose has 1/60th the TCR of nickel. That's going to be a 120F distortion. As the TCR gets smaller, this kind of problem gets bigger. Even copper wiring has a TCR.

Sometimes screwing in an atomizer slightly differently can shift its resistance some fraction of a percent. If (say) 400F is 1%, how can you hope to get the vape consistent?

There's an electrical noise problem at a certain point. Suppose you have a 1 Ohm atomizer and can read to 1 mV / 1 mA. At 25 watts, it's 5V, 5A. If (say) 400F is 1%, 1.01 Ohms is 5.025V, 4.975A. You've got 25 values between 70F and 400F, so a single bit of electrical noise on either voltage or current will be 13 degrees. That's going to be a rather bouncy vape.

etc.

[FnZ]

@James many thanks for your reply and sorry for the delay but I was out for long time (vacancy)