Joyetech Evic VT 60 Watt

Status
Not open for further replies.

aldenf

Ultra Member
ECF Veteran
Verified Member
Jun 26, 2014
2,558
10,293
NYC, NJ, USA
Ok, I wasn't clear. If the vt is locked at a specific res it appears to ignore the "actual" res of the atty. So if your atty res drops or rises the vt applies voltage as if the res didn't change. So if your atty res drops your actual wattage will be greater; if your atty res rises your actual wattage will be less. At least that's what appears to be happening.

That can't be right, Cig. Locking the resistance is simply for determining temperature for limiting. Locking is to take place when the mod and atty are at the same temperature simply to give the chipset a baseline for guessing the temp. The device still has to know the current resistance of the atty at every point of use in order to supply the correct voltage to achieve the set wattage.
 

JeremyR

Vaping Master
ECF Veteran
Dec 29, 2012
6,611
14,052
48
Oregon, IL
Actually, the SX Mini or the IPV4 is a good test bed to check the resistance of the coil on since with the Yihi chip you can force a new reading on the coil. So I took the Subtank Mini with the nickel OCC and put it on the SX Mini and pressed both the up and down buttons. It had been sitting there unused for probably 15 minutes to half an hour. The resistance came up as 0.201 ohms. Pressed both again and the resistance dropped to 0.192 ohms. Vaped it once at 40 joules and 450 degrees. Let it sit for 5 minutes. Checked the resistance again and it read as 0.143 ohms. Vaped it once again and let it sit for 5 minutes and then checked the resistance and it read as 0.128 ohms. Let it sit for a few minutes and checked resistance again and it read as 0.134 ohms. Checked it again and it read as 0.129 ohms. So basically with the coil I have in the Subtank Mini right now, that initial resistance reading is about 0.07 ohms high, but then over time it settles down to be roughly around 0.13 ohms.

This is the same result that I am getting with both the rDNA40 and the evic-VT. It starts out high, and then it settles down and stays constant at 0.13 ohms.

With the Yihi chip, since you have to manually set the resistance by "registering" it, the lock works because once you set it, the resistance never changes. With the rDNA40 and the evic-VT, it appears that the mod is always validating the resistance and it will change, even if the lock is activated.

I also took the Atlantis v2 with the nickel coil that I was using on the SX Mini and put it on the evic-VT. It registered at 0.14 ohms and stayed constant at 0.14 ohms.

So based on my total unscientific testing, it appears that the OCC coils are much more subject to these resistance jumps than the Atlantis coils. I'm much more confident that the issue lies with the coils and not with the mod.

So basically like I thought its normal operation.. You can't totally lock it because it would still fire with a short! Coils can and DO fluctuate. Ohm Readings to the hundredth are going to show a picture many, like myself, have never seen before.

The joyetech boards do seem to sample resistance different than most other mods.. It seems more live and active on the istick 50w too.

This is a very sofisticated device that is very sensitive. A good coil and connection is essential.

If your coil fluctuates how is that the vts problem.
 
Last edited:

cigatron

Vaping Master
ECF Veteran
May 14, 2014
3,213
13,374
clinton ar
That can't be right, Cig. Locking the resistance is simply for determining temperature for limiting. Locking is to take place when the mod and atty are at the same temperature simply to give the chipset a baseline for guessing the temp. The device still has to know the current resistance of the atty at every point of use in order to supply the correct voltage to achieve the set wattage.

I thought we were talking about the preheat wattage only. That the problem was varying heatup times as atty res fluctuates. Still, the baseline res is moot if it changes. My bad.
 
  • Like
Reactions: aldenf

atroph

Super Member
ECF Veteran
Verified Member
Jun 23, 2014
830
1,656
Chesapeake, VA
Locked at .15 and hitting at .12 is plausible as it depends on what the conditions were when the coil was locked. The resistance always varies depending on what the temperature of the coil is.

If the atty is hot the coil will have higher resistance. The mod has no clue if the atty is hot or not, it just compares the resistance when locked to the ambient temperature. So at .15 ohms at 70F ambient air it believes that the atty is at 70F too. That is what locking does (in theory).

If my math is correct a 0.02 difference in ohms nets about a 10F degree difference in temperature.

Given:
Atty locked at 70F or 21C
Resistance is 0.15ohms
coefficient 0.006 (ni200)

Resistance changed to 0.12ohms

Solve for temp:
Temp of atty is now 60F or 16C

What are you changing your temp to in order to restore your previous vape experience? 10, 20, 30 F?

Ideally a mechanical connection is much much better like screws holding down the wire vice the pin/grommet method of the kanger coils. Maybe it would be a good idea to wiggle the pin or give it a twist to "hopefully" secure the metal to metal contact a little better.... I believe the aspire coils actually crimp the coil wire at the top of the head, and have a pin at the bottom just like the kanger.

Also what is the big hangup with watts? Why care about the watts? The way the device is designed the amount of watts delivered at any point is a moving target since the temperature is all over the place until it reaches it desired temp. Airflow and wick saturation control the heat dissipation of the coil and the mod compensates with more power. Lessen the juice or air and down the power goes. You could have it deliver 1.21 Giga-watts at the press of the button, but it would limit down to something much lower once the temp is up to what you want. Is there that much "preheat" difference between 30W and 50W? Why not just set it at 50W and your desired temp and vape away? IMO watts are irrelevant with this and any TC mod...but like I said earlier I don't have mine yet.
 
Last edited:

workman70

Senior Member
ECF Veteran
Verified Member
Nov 21, 2014
161
194
Knoxville, TN
Locked at .15 and hitting at .12 is plausible as it depends on what the conditions were when the coil was locked. The resistance always varies depending on what the temperature of the coil is.

If the atty is hot the coil will have higher resistance. The mod has no clue if the atty is hot or not, it just compares the resistance when locked to the ambient temperature. So at .15 ohms at 70F ambient air it believes that the atty is at 70F too. That is what locking does (in theory).

If my math is correct a 0.02 difference in ohms nets about a 10F degree difference in temperature.

Given:
Atty locked at 70F or 21C
Resistance is 0.15ohms
coefficient 0.006 (ni200)

Resistance changed to 0.12ohms

Solve for temp:
Temp of atty is now 60F or 16C

What are you changing your temp to in order to restore your previous vape experience? 10, 20, 30 F?

Ideally a mechanical connection is much much better like screws holding down the wire vice the pin/grommet method of the kanger coils. Maybe it would be a good idea to wiggle the pin or give it a twist to "hopefully" secure the metal to metal contact a little better.... I believe the aspire coils actually crimp the coil wire at the top of the head, and have a pin at the bottom just like the kanger.

Also what is the big hangup with watts? Why care about the watts? The way the device is designed the amount of watts delivered at any point is a moving target since the temperature is all over the place until it reaches it desired temp. Airflow and wick saturation control the heat dissipation of the coil and the mod compensates with more power. Lessen the juice or air and down the power goes. You could have it deliver 1.21 Giga-watts at the press of the button, but it would limit down to something much lower once the temp is up to what you want. Is there that much "preheat" difference between 30W and 50W? Why not just set it at 50W and your desired temp and vape away? IMO watts are irrelevant with this and any TC mod...but like I said earlier I don't have mine yet.

The difference is the temp protection. If it set to a gigawatt, the coil will immediately hit temp protection and not fire at all. The key is to set the wattage so that you approach temp protection but not slam into it. If wattage is too high it will cycle in temp protection more frequently than a wattage that may put you just over your desired temp.
 
  • Like
Reactions: atroph

vincom

Ultra Member
ECF Veteran
Jun 19, 2014
1,151
1,948
Philippines
watts and temp never made sense to me.
if i set it at a certain temp why would i need to change or use watts/joules(power).
if watts is for ramp up time who wouldnt want fast ramp up time and just set power to max. its going to reach my set temp faster.
reviewers arent helping when they dont differentiate the power and temp settings or dont dwell/talk about it that much. some have actually stated that they dont get it either.
i guess until i get one i wont know
 

cigatron

Vaping Master
ECF Veteran
May 14, 2014
3,213
13,374
clinton ar
Locked at .15 and hitting at .12 is plausible as it depends on what the conditions were when the coil was locked. The resistance always varies depending on what the temperature of the coil is.

If the atty is hot the coil will have higher resistance. The mod has no clue if the atty is hot or not, it just compares the resistance when locked to the ambient temperature. So at .15 ohms at 70F ambient air it believes that the atty is at 70F too. That is what locking does (in theory).

If my math is correct a 0.02 difference in ohms nets about a 10F degree difference in temperature.

Given:
Atty locked at 70F or 21C
Resistance is 0.15ohms
coefficient 0.006 (ni200)

Resistance changed to 0.12ohms

Solve for temp:
Temp of atty is now 60F or 16C

What are you changing your temp to in order to restore your previous vape experience? 10, 20, 30 F?

Ideally a mechanical connection is much much better like screws holding down the wire vice the pin/grommet method of the kanger coils. Maybe it would be a good idea to wiggle the pin or give it a twist to "hopefully" secure the metal to metal contact a little better.... I believe the aspire coils actually crimp the coil wire at the top of the head, and have a pin at the bottom just like the kanger.

Also what is the big hangup with watts? Why care about the watts? The way the device is designed the amount of watts delivered at any point is a moving target since the temperature is all over the place until it reaches it desired temp. Airflow and wick saturation control the heat dissipation of the coil and the mod compensates with more power. Lessen the juice or air and down the power goes. You could have it deliver 1.21 Giga-watts at the press of the button, but it would limit down to something much lower once the temp is up to what you want. Is there that much "preheat" difference between 30W and 50W? Why not just set it at 50W and your desired temp and vape away? IMO watts are irrelevant with this and any TC mod...but like I said earlier I don't have mine yet.


Well put, exactly how I see it except for your take on preheat. If you set your preheat higher than the wattage you'll be TPing at others have noted that the vape isn't as smooth. Like it's temporally shuting off the voltage until it cools enough to fall below TP. I don't know, don't have a VT. Just about to pull the trigger though!
 

workman70

Senior Member
ECF Veteran
Verified Member
Nov 21, 2014
161
194
Knoxville, TN
It's really kind of a dance. You can set it high and try it that way. With the watts set there, it briefly cuts out and adjusts down to try to reach set temp, but the high wattage is the baseline it wants to get back to, so it backs down the wattage, but still want to increase to get back to baseline, but the programming steps on it. It makes it work too hard in my opinion.

The temp also affects this. So, there's lots of variables. It takes tinkering, but once you find your spot, you're all good. If you want to vape any juice at 500*, regardless of resistance, you will have to adjust the wattage or joules, depending on what TP device you are using. I think people try to slam the wattage so they can set it and forget. And maybe I'm wrong as to exactly how it works, but that is how it appears to function in my experience.
 
  • Like
Reactions: aldenf

aldenf

Ultra Member
ECF Veteran
Verified Member
Jun 26, 2014
2,558
10,293
NYC, NJ, USA
Locked at .15 and hitting at .12 is plausible as it depends on what the conditions were when the coil was locked. The resistance always varies depending on what the temperature of the coil is.

If the atty is hot the coil will have higher resistance. The mod has no clue if the atty is hot or not, it just compares the resistance when locked to the ambient temperature. So at .15 ohms at 70F ambient air it believes that the atty is at 70F too. That is what locking does (in theory).

If my math is correct a 0.02 difference in ohms nets about a 10F degree difference in temperature.

Given:
Atty locked at 70F or 21C
Resistance is 0.15ohms
coefficient 0.006 (ni200)

Resistance changed to 0.12ohms

Solve for temp:
Temp of atty is now 60F or 16C

What are you changing your temp to in order to restore your previous vape experience? 10, 20, 30 F?

Ideally a mechanical connection is much much better like screws holding down the wire vice the pin/grommet method of the kanger coils. Maybe it would be a good idea to wiggle the pin or give it a twist to "hopefully" secure the metal to metal contact a little better.... I believe the aspire coils actually crimp the coil wire at the top of the head, and have a pin at the bottom just like the kanger.

Also what is the big hangup with watts? Why care about the watts? The way the device is designed the amount of watts delivered at any point is a moving target since the temperature is all over the place until it reaches it desired temp. Airflow and wick saturation control the heat dissipation of the coil and the mod compensates with more power. Lessen the juice or air and down the power goes. You could have it deliver 1.21 Giga-watts at the press of the button, but it would limit down to something much lower once the temp is up to what you want. Is there that much "preheat" difference between 30W and 50W? Why not just set it at 50W and your desired temp and vape away? IMO watts are irrelevant with this and any TC mod...but like I said earlier I don't have mine yet.

Agreed. Ideally, we wouldn't need control of the watts at all, just the temp. The chipset would magically do the rest. I think this exact/finite technology is unable to accurately regulate in this environment, given all the variables. Like many have said, it is reasonably guess-timating the temp of the coil. Taking a bit of control of the process by setting wattage close to what is necessary to maintain our desired temperature, simply smooths and enhances the vaping experience. These are the limitations of this technology or, at least, its current implementation. We need to adjust our expectations. I believe, at this moment in time, what we have is temperature limiting, not temperature control. To use an automotive analogy, what we have is adjustable governing not cruise control. Who knows what next month will bring us? Just my :2c:
 

vincom

Ultra Member
ECF Veteran
Jun 19, 2014
1,151
1,948
Philippines
right, who knows what next month will bring us.
innokin is already talking about releasing temp control/limit mod using any wire, even kanthal.
how, no one knows yet as it was thought impossible to do any temp limit using kanthal.
hence im still on the fence using my antiquated 30 vw/vv device.......and luvin it, dead simple to use.
 

workman70

Senior Member
ECF Veteran
Verified Member
Nov 21, 2014
161
194
Knoxville, TN
Agreed. Ideally, we wouldn't need control of the watts at all, just the temp. The chipset would magically do the rest. I think this exact/finite technology is unable to accurately regulate in this environment, given all the variables. Like many have said, it is reasonably guess-timating the temp of the coil. Taking a bit of control of the process by setting wattage close to what is necessary to maintain our desired temperature, simply smooths and enhances the vaping experience. These are the limitations of this technology or, at least, its current implementation. We need to adjust our expectations. I believe, at this moment in time, what we have is temperature limiting, not temperature control. To use an automotive analogy, what we have is adjustable governing not cruise control. Who knows what next month will bring us? Just my :2c:

I would agree. There are smarter people out there that will figure out something better, but with so many variable, including draw, it will be a significant challenge. It is a funny thing, as two people vaping TP at *500 can and likely will have completely different settings based on draw, but still have the same experience.
 
  • Like
Reactions: cigatron

USMCotaku

ECF Guru
ECF Veteran
Apr 25, 2014
11,877
45,735
California
right, who knows what next month will bring us.
innokin is already talking about releasing temp control/limit mod using any wire, even kanthal.
how, no one knows yet as it was thought impossible to do any temp limit using kanthal.
hence im still on the fence using my antiquated 30 vw/vv device.......and luvin it, dead simple to use.
They are using an in tank sensor, which is why as of now only their isub TC tank will work with kanthal
 
  • Like
Reactions: aldenf

workman70

Senior Member
ECF Veteran
Verified Member
Nov 21, 2014
161
194
Knoxville, TN
right, who knows what next month will bring us.
innokin is already talking about releasing temp control/limit mod using any wire, even kanthal.
how, no one knows yet as it was thought impossible to do any temp limit using kanthal.
hence im still on the fence using my antiquated 30 vw/vv device.......and luvin it, dead simple to use.

The Smok M80plus, already does...it's just wattage bucking
 

refuzeandrezizt

Senior Member
ECF Veteran
Verified Member
Feb 6, 2015
118
134
48
Western, KY
Sure does

So they are for sure spring loaded now? Seems the early versions were not, and some people thought they would implement it in the final release. Seems there was also a revision on the software too. I just wonder if all the early shipped units have all these "updates".
 
Status
Not open for further replies.

Users who are viewing this thread