DNA40 Wrong Resistance = No Temp Control?

[Caterpiller]

I recently bought a Vapor Flask (authentic) with DNA40.

The temp control gives both F and C options, but I notice that it has very poor ohms reading.

Having tried four atty"s which I had verified for ohms, it has proven to read all of them low.

All my atty's are between 1 - 1.8 ohms.

VF DNA40 reads them between 0.4 - 1.3 ohms lower than they actually are. Most of the time it's out by 0.8 ohms.

This is no real problem for me due to my preference for high ohm builds and ability to verify the correct ohms reading using other devices, meters, etc...

But I wouldn't trust it with a temp control build. Surely if it doesn't get the ohms correct this would massively effect the calculations for temp control?

Being an optimist, I wonder if they have calibrated the DNA40 internal ohms meter to only be very accurate for sub-ohms builds - where temp control would come into effect, or only accurate for Nikel wire?

 

[edyle]

I think it more likely you overtightened the 510 connection, depressing the centerpin, causeing a partial short.

Happens a lot with regulated mods.

 

[Caterpiller]

I think it more likely you overtightened the 510 connection, depressing the centerpin, causeing a partial short.

Happens a lot with regulated mods.

It would be great if that was it. I'll have a look when I get home - I'm at work with another setup.

Are you saying I could be pushing too hard on the spring loaded 510 pin built into the VF, by screwing the atty's on too tight?

 

[edyle]

It would be great if that was it. I'll have a look when I get home - I'm at work with another setup.

Are you saying I could be pushing too hard on the spring loaded 510 pin built into the VF, by screwing the atty's on too tight?

If it's got a spring loaded centerpin then your shouldn't have the overtightening problem.

 

[dr g]

The DNA system boards are extremely accurate resistance measuring devices and if you are comparing to a typical cheap vaping ohm checker, that is the far less accurate device.
Also, in temperature mode, the displayed resistance is a normalized reference value, not a live resistance reading.

 

[Caterpiller]

The DNA system boards are extremely accurate resistance measuring devices and if you are comparing to a typical cheap vaping ohm checker, that is the far less accurate device.

Also, in temperature mode, the displayed resistance is a normalized reference value, not a live resistance reading.

I've never put my VF DNA40 in temp mode, but in VW mode it is far from accurate, normally about 0.8 ohms under as mentioned above.

I have verified this by carefully measuring lenghts of wire and putting them on a top end volt meter before making the coil, reffering to steam engine to confirm the reading matches expectation. Building the coils, then back on the volt meter, placing in the deck then back on volt meter, double checked on cheap vaping meter, triple checked on alternative mods.

I've done this for my own builds and OCC's, and the only readings that don't correspond are coming from the FV DNA40.

So I strongly suspect, my one at least, has a very poor meter reader.

 

[dr g]

Something is wrong, as stated DNAs are extremely accurate (current sensing). Could be between the board and the atty as well.

 

[Pocha]

If I were you I'd join the Vapor Flask owners page on Facebook and PM Preston Kight. He'll be able to help you out. Ive never heard of a Flask having this problem but I guess there's a first time for everything,

 

[Caterpiller]

If I were you I'd join the Vapor Flask owners page on Facebook and PM Preston Kight. He'll be able to help you out. Ive never heard of a Flask having this problem but I guess there's a first time for everything,

Thanks Pocha, if it becomes a problem I'll try that. Although I've gone this far without joining Facebook and hope I never have to.

To be honest I bought the VF because I love the form factor, and I'm still very happy with it.

I wasn't really planning on using the temp control. I've heard Nickel coils are a huge pain to work with, and I'm just getting used to building Kanthal.

It would have been nice to have the option later though.

Before I can say for 100% sure the VF temp control is not working for me, I'd have to give it a try.

But for now I'll stick with my VW Kanthal builds.

Just noticed something else this evening. I built a new 1.82 Ohm coil (read 1.72 on my VF), and went to dry pulse the coil on the deck, just to check the coil before wicking, and Temperature Protection kicked in.

This even in VW mode with TC turned off.

Bit of a pain. The coil looked good cold, so I wicked it without adjustment and it's vaping fine.

Still it would be nice to be able to run the coil through a few pulses to check it, without having to stick the deck on another mod.

 

[dr g]

Ok so if you are getting temp control messages, you do not have it off.

 

[Caterpiller]

Ok so if you are getting temp control messages, you do not have it off.

It was a Temperature Protection lock, and not a Temperature Control function.

I'm not entirely sure how related these two are?

I was fairly confident that I'd turned TC off, as I've only been building with Kanthal, and the screen is only showing Watts, Volts, Ohms (no temp), and I remember turning TC off.

Have you managed to dry burn a coil on a DNA40?

 

[dr g]

There is no lock associated with temperature protection/control, it's just either on or off. To turn it off, increase set temperature above the maximum.

 

[TheotherSteveS]

Have you managed to dry burn a coil on a DNA40?

well if you set the temp to 500F it will burn on most setups, so yeah!

 

[dr g]

well if you set the temp to 500F it will burn on most setups, so yeah!

No it won't.

 

[TheotherSteveS]

No it won't.

wot? ok 550F then..to be clear I assume he means dry cotton!!

 

[dr g]

I think he means no cotton

 

[TheotherSteveS]

I think he means no cotton

ok! missed that!

 

[Caterpiller]

Yes dry burn without cotton.

I put the VF in temp control mode, then 1 click up from either 300c or 600f reads OFF.

So I'm assuming the temp control is then off.

But when I went to dry burn the VF powered off and said Temperature Protection on the screen.

 

[dr g]

hmm, try going to F first then shutting it off.