Joyetech Evic VT 60 Watt

[USMCotaku]

My experience with the vt it DOES do it well, on a stable build. Those other chips may appear to be doing it well because you don't see the fluctuations once locked, but that may be false security. If the coil ohms are "wandering" due to bad contacts for example, just because you don't see it once locked, doesn't mean that the vape won't be effected. Could be some placebo effect going on there.... Don't know the changes are going on, don't notice the temp differences, see the changes and omg look how much the temp changes.
Sent with one hand, the other is busy vaping.

 

[AnsonJames]

My experience with the vt it DOES do it well, on a stable build. Those other chips may appear to be doing it well because you don't see the fluctuations once locked, but that may be false security. If the coil ohms are "wandering" due to bad contacts for example, just because you don't see it once locked, doesn't mean that the vape won't be effected. Could be some placebo effect going on there.... Don't know the changes are going on, don't notice the temp differences, see the changes and omg look how much the temp changes.
Sent with one hand, the other is busy vaping.

I think some VT's are doing it well, mine doesn't appear to be.
I've been using temp control for a long time now - so I'm adept enough at building stable Nickel coils.

 

[cigatron]

My experience with the vt it DOES do it well, on a stable build. Those other chips may appear to be doing it well because you don't see the fluctuations once locked, but that may be false security. If the coil ohms are "wandering" due to bad contacts for example, just because you don't see it once locked, doesn't mean that the vape won't be effected. Could be some placebo effect going on there.... Don't know the changes are going on, don't notice the temp differences, see the changes and omg look how much the temp changes.
Sent with one hand, the other is busy vaping.

Couldn't agree with this more.....and I wouldn't spend a dollar more for a yihi or dna chip. My VT is just as stable as the build and device attached to it.

 

[BNEAT]

My experience with the vt it DOES do it well, on a stable build. Those other chips may appear to be doing it well because you don't see the fluctuations once locked, but that may be false security. If the coil ohms are "wandering" due to bad contacts for example, just because you don't see it once locked, doesn't mean that the vape won't be effected. Could be some placebo effect going on there.... Don't know the changes are going on, don't notice the temp differences, see the changes and omg look how much the temp changes.
Sent with one hand, the other is busy vaping.

would you like to trade your eVic for mine?

100° change in temp is the placebo effect? Besides, my DNA40 doesn't have Atty Lock. (And doesn't need it)

 

[JeremyR]

Ok you guys that have done tc for a while can ignore this if you feel.

But dropping .02 in resistance doesn't seem to indicate a flaw. It indicates that the build wasn't fully cold when you put it on or selected new coil. It will readjust if it the coil lowers when fully cooled.

Look at page 5 of the manual and read the vt directions closely.

EvicVTmanual.pdf - Google Drive


Very interesting bikenstien, that it can take up to 20min to fully cool a coil. One single pulse can jump the ohms and it will take a while to cool back to ambient. When it does it will refine to the correct ambient res.

 

[Bikenstein]

Personally, I think the VT, from what I'm reading here, is doing a good job of temp control regardless of what you see on the screen. I think the new istick 40w TC will too. I know that the coil ohms wander or change as the coil heats up even though I can't see it on my SX and VaporShark. That doesn't bother me because that's how the chip determines the temp based on the changes in res. I still like the performance of the Yihi better than the DNA 40 but not much. I have a VT ordered and am lookin forward to it. @atroph The temperature coefficient of resistance of Ti is .0035.

 

[Bikenstein]

Ok you guys that have done tc for a while can ignore this if you feel.

But dropping .02 in resistance doesn't seem to indicate a flaw. It indicates that the build wasn't fully cold when you put it on or selected new coil. It will readjust if it the coil lowers when fully cooled.

Look at page 5 of the manual and read the vt directions closely.

EvicVTmanual.pdf - Google Drive


Very interesting bikenstien, that it can take up to 20min to fully cool a coil. One single pulse can jump the ohms and it will take a while to cool back to ambient. When it does it will refine to the correct ambient res.

If the VT only reads to hundreths of an ohm, which I think it does, it won't be as noticeable (to the eye). But with the Yihi chip reading to thousandths of an ohm you can see it takes a remarkably long time to return to normal temp.

 

[foggybottom]

Correct. What does a 0.5 ohm ti coil at vape temperature ohm out to? I am guessing it is close to if not above 1 ohm thus when you remove and replace the hot head it flips to vw mode. Just a guess.

I can figure the math if anyone knows the ti coefficient off the top of their head.

Actually, I raised this possibility earlier when the flipping out of temp to power issue hit the fan, but found it unlikely because of the numbers. I think it goes like this:
Change in Temp (C)= (Final resistance - Starting resistance)/(coefficient of resistance x starting resistance). Thanks to TheBloke for this. Using the Ti coefficient of 0.0038, my ambient coil resistance of 0.41, the resistance of the heated coil screwed back on of 0.54 I get the following:
Temp of the coil when I screw it back on = 194 F
Change in Temp required to take Ti ohms up from 0.54 to 1.0 = 435 F
Final temp of coil = 629 F
Is this possible with a brief tap of the fire button? I guess so. For what it's worth, I tried replicating it but I can do it only if I set my temp to 600 F in Temp ti mode so yeah, that may be what is happening.

 

[Carnage9270]

It has nothing to do with the device "changing psychical properties" of the coil - the electronics and software are supposed to deal with heat
effecting the resistance change by keeping the power level the same based on the original "locked" reading - but it's not staying locked.


The Yihi temp control chips can do it, as can the later versions of the DNA 40 - the VT can't do it very well - apparently.

Doesn't matter what "lock" is supposed to mean. They aren't really locking anything. They are adjusting wattage and voltage to achieve a fake resistance lock. People say it works well...none of them do. I own them all and they all do something different to achieve the same result. Your resistance changes regardless and there's nothing they can do to stop it other than give you a different reading on the lcd screen than what is actually there. But to say it is locking your resistance is very misleading. It's all calculations based on the difference between your baseline "locked" resistance and the current resistance it is reading and applies what it thinks is going to give you the same vape so you don't notice it. My Evic does this very well as long as the resistance doesn't vary too much. A quality topper is mandatory with the Evic, but in my opinion it works fantastically for the price tag and 10 times better than the early DNA 40's.

 

[JeremyR]

Actually, I raised this possibility earlier when the flipping out of temp to power issue hit the fan, but found it unlikely because of the numbers. I think it goes like this:

Change in Temp (C)= (Final resistance - Starting resistance)/(coefficient of resistance x starting resistance). Thanks to TheBloke for this. Using the Ti coefficient of 0.0038, my ambient coil resistance of 0.41, the resistance of the heated coil screwed back on of 0.54 I get the following:
Temp of the coil when I screw it back on = 194 F
Change in Temp required to take Ti ohms up from 0.54 to 1.0 = 435 F
Final temp of coil = 629 F
Is this possible with a brief tap of the fire button? I guess so. For what it's worth, I tried replicating it but I can do it only if I set my temp to 600 F in Temp ti mode so yeah, that may be what is happening.

Yeah when I fooled it to think the coil was over .1 ohms higher. It put an emense amount of power into the coil. Due to the .1+ difference when calculating the voltage for wattage requested. So I noticed instant super hot. Instead of 50w it calculated an actual 67w with the real resistance.


The manual says if it goes over 1 ohm it will automatically change to vw. So obviously something happened that it read 1 ohm as the base res and flipped. You can set to to ti mode but when you fire it automatically changes to vw.

 

[AnsonJames]

I have 2 VT's, one of them works perfect but the other has a variety of different issues. Seems like they just have poor quality control.

What issues are you having with your dodgy unit?

 

[BNEAT]

Hey BNEAT, maybe you should contact the seller about warranty? Looks like yours doesn't work as it should. Mine did drop .01 today, but thats after almost a week of using the same coil, and abusing my setup big time.

Oh, it's definitely going back. Even though I'm sure mine is just a defect of some sort, I'm going to wait until there's a for-sure firm ware update. I'm hoping they update the Ti coefficient, too.

What resistance/material coil were you using when it dropped .01? (My ADV tank does the same thing in my DNA40 after a week or so of gunk build up)

 

[janne303]

Going back? According to Joyetech its no faults with Vt?hehe

Skickat från min D6503 via Tapatalk

 

[cdrice15]

Just got the evic VT as a back up to my sx mini. Got my stm with a nickel build I've been running for 3 days on the sx. Ran the sx at 400f but had to go 450f on the evic for the same vape. Gonna try it for a few days to see how it does.

 

[BNEAT]

Just got the evic VT as a back up to my sx mini. Got my stm with a nickel build I've been running for 3 days on the sx. Ran the sx at 400f but had to go 450f on the evic for the same vape. Gonna try it for a few days to see how it does.

That's interesting: my nickel builds vape at the same temp on my devices. (Ti is where things get really interesting)

 

[JeremyR]

Just got the evic VT as a back up to my sx mini. Got my stm with a nickel build I've been running for 3 days on the sx. Ran the sx at 400f but had to go 450f on the evic for the same vape. Gonna try it for a few days to see how it does.

Did both register the same resistance. Maybe the sx was locked at ~.01, .02 higher than on the vt after vt refined it.

That would cause a difference in temp setting, no?

 

[BNEAT]

Did both register the same resistance. Maybe the sx was locked at ~.01, .02 higher than on the vt after vt refined it.

That would cause a difference in temp setting, no?

I assumed he meant at the same resistance...and you know what they say about aśś-u-me

 

[Bikenstein]

Doesn't matter what "lock" is supposed to mean. They aren't really locking anything. They are adjusting wattage and voltage to achieve a fake resistance lock. People say it works well...none of them do. I own them all and they all do something different to achieve the same result. Your resistance changes regardless and there's nothing they can do to stop it other than give you a different reading on the lcd screen than what is actually there. But to say it is locking your resistance is very misleading. It's all calculations based on the difference between your baseline "locked" resistance and the current resistance it is reading and applies what it thinks is going to give you the same vape so you don't notice it. My Evic does this very well as long as the resistance doesn't vary too much. A quality topper is mandatory with the Evic, but in my opinion it works fantastically for the price tag and 10 times better than the early DNA 40's.

So none of them work well but the Evic works fantastically? I'm usin a GD Air on y SX and DNA 40 so I don't think a "quality topper is necessarily mandatory. It may be for the Evic, but I'll try it when mine comes in from China. I'm not sure what's goin on with the locking of the base res. I fooled my SX into a .01ohm higher base res and it still vapes the same.

 

[Carnage9270]

So none of them work well but the Evic works fantastically?

It's amazing the inflection one gets with words when they exclude the next four words after "fantastically".

 

[dr3d]

This is a gigantic point of confusion. The Evic VT does not have a "Resistance Lock." The Evic VT does have an "Atomizer Lock." Many of us are confused because of cross-device differences which we are mistakenly perceiving as similarities.

The Evic VT does not ever try to lock a resistance. Rather, it constantly refines the base resistance regardless of whether or not an atomizer has been locked.

So, what is this atomizer lock? It is simply a tool the Evic VT uses to avoid losing refinement ground when an atomizer that is in use is pulled and then replaced. This is useful when I do something like filling a tank that I have been actively vaping. If I have the atomizer locked, I am able to avoid starting a new refinement process with a warm coil and in-theory, I should enjoy the same experience I had before draining the tank.

I believe my understanding is correct. That said, I would prefer a mod with an actual resistance lock. The Evic VT simply does not lock resistances. Coil temperatures are calculated based on the difference between current measured resistance and the base reference resistance. We do not control the base reference resistance.