Measured 18650 voltage

[dywersant]

Hello everyone.
I got my Finder 167 Dna250 mod a week ago. Right after my charger (Xtar vc2) finished charging my batts i put them into Finder and started peeking around device monitor. So right off the bat i saw that my cells voltage at 4,25/4,27 Volts. So either my charger is overcharging, or the dna is wrong. Another possibility is, that theres something assembled incorrectly inside the mod.
If anyone else can comment on their findings, since this issue is buggering me?

I did some further testing, i have a vt133 and a multimeter laying around. Here is what i could measure, using different sets of cells:

	Finder167	Vt133	Multimeter
Straight out of charger	4,25/4,27	4,22/4,23	4,18/4,19
	3,45/3,43	3,41/3,39	3,37/3,35
	4,17/4,17	4,14/4,13	4,08/4,09
	3,67/3,67	3,64/3,64	3,60/3,60

[retird]

You might take the batteries that are 3.45 volts or below and charge them in the Finder and the VT and see what they charge up to with the on board chargers. That may help determine if the xtar is overcharging.... note that meters are never 100% accurate....  

[MM22]

@dywersant

Hi, this is my first post here, I was going to open a support ticket for your same problem.

I have a Lost Vape Triade DNA 250 Box Mod.

After charging my Samsung 25R5 (green ones, I love them, I use them for everything) I double checked them with professional equipment, not 20$ multimeters, 'cause I'm lucky to have a whole team of Avionic Technicians ready to help me with my stupid requests, such as testing cells voltage or checking resistance values. And as you can easily imagine, they have all those fancy instruments capable of doing whatever you want, so I don't think that my DNA 250 board (which I absolutely love, but there are obvious differences between a 80$ board made for vaping, and super-professional instruments) is reading correct while those instruments are overcharging my cells or not reading correct.

 

So I am 10000% certain that my cells are @4.20V Â± 0.1mV

 

But my board is reading 4.25/4.27V everytime I put 3 charged cells in.

It is reading this:

-in the device monitor;

-in the on-screen voltage reader, cause I like to see my 3 individual cell voltage meters everywhere, instead of seeing my locked ohms or my puffs counter or whatever, cause I love to see the Voltage drop when I take a puff


Another thing I noticed is that the first time i put full batteries in the board is reading all three cells above 4.25 but always different and strictly increasing values between them, for example:

Cell 1 @4.25
Cell 2 @4.26
Cell 3 @4.27

If I take out my cells and swap them, so the third one for example becomes the first one or the second one, the voltage reading decreases, I don't know why, ALWAYS @4.22V for all of the three cells, so after swapping them the board is reading:

Cell 1 @4.22
Cell 2 @4.22
Cell 3 @4.22

I'm probably going to open a ticket if I don't find any answer here in the forum and let you know what they tell me.

I know very well that meters are never 100% accurate, but 0.05V is unacceptable: if the board isn't reading correct, it means that it's not able to charge my cells properly, and I want my mod to charge my cells properly 'cause the famous 2A and other fancy things charge on the DNA 250 is one of the most advertised things about it.

Another issue that i HATE. The room temperature sensor... it's always reading AT LEAST 5°C more than the real value. It's not my hand that is warm and it's heating the case, cause I always leave my mod overnight in a room set at exactly 19°C, and when I check the room temperature reading (I also tried to check it without touching the mod, leaving the USB cord attached just to the mod before going to bed, ready to connect to eScribe) it's ALWAYS reading something between 26°C to 29°C.

They could just give us the opportunity to calibrate our board sensors, in my opinion.


Oh, I never tried charging my cells inside my MOD, I always use external chargers. I hope this is a firmware-related issue.

[Spector NS5 RD]

MM22 said:

@dywersant

Hi, this is my first post here, I was going to open a support ticket for your same problem.

I have a Lost Vape Triade DNA 250 Box Mod.

After charging my Samsung 25R5 (green ones, I love them, I use them for everything) I double checked them with professional equipment, not 20$ multimeters, 'cause I'm lucky to have a whole team of Avionic Technicians ready to help me with my stupid requests, such as testing cells voltage or checking resistance values. And as you can easily imagine, they have all those fancy instruments capable of doing whatever you want, so I don't think that my DNA 250 board (which I absolutely love, but there are obvious differences between a 80$ board made for vaping, and super-professional instruments) is reading correct while those instruments are overcharging my cells or not reading correct.

 

So I am 10000% certain that my cells are @4.20V Â± 0.1mV

 

But my board is reading 4.25/4.27V everytime I put 3 charged cells in.

It is reading this:

-in the device monitor;

-in the on-screen voltage reader, cause I like to see my 3 individual cell voltage meters everywhere, instead of seeing my locked ohms or my puffs counter or whatever, cause I love to see the Voltage drop when I take a puff


Another thing I noticed is that the first time i put full batteries in the board is reading all three cells above 4.25 but always different and strictly increasing values between them, for example:

Cell 1 @4.25
Cell 2 @4.26
Cell 3 @4.27

If I take out my cells and swap them, so the third one for example becomes the first one or the second one, the voltage reading decreases, I don't know why, ALWAYS @4.22V for all of the three cells, so after swapping them the board is reading:

Cell 1 @4.22
Cell 2 @4.22
Cell 3 @4.22

I'm probably going to open a ticket if I don't find any answer here in the forum and let you know what they tell me.

I know very well that meters are never 100% accurate, but 0.05V is unacceptable: if the board isn't reading correct, it means that it's not able to charge my cells properly, and I want my mod to charge my cells properly 'cause the famous 2A and other fancy things charge on the DNA 250 is one of the most advertised things about it.

Another issue that i HATE. The room temperature sensor... it's always reading AT LEAST 5°C more than the real value. It's not my hand that is warm and it's heating the case, cause I always leave my mod overnight in a room set at exactly 19°C, and when I check the room temperature reading (I also tried to check it without touching the mod, leaving the USB cord attached just to the mod before going to bed, ready to connect to eScribe) it's ALWAYS reading something between 26°C to 29°C.

They could just give us the opportunity to calibrate our board sensors, in my opinion.


Oh, I never tried charging my cells inside my MOD, I always use external chargers. I hope this is a firmware-related issue.

can't really comment on the high cell readings. just one question about it tho, if you charge the cells INSIDE the mod what are read values for each of the 3 cells, 4.20v? if so, i'd be happy with that. 

as for ambient temp sensors on the board not being calibrated, that's Lost Vapes job to run case analyzer. case analyzer will account for added heat during the charge/normal operation of the board. those results are factored into the room temp reading. the room temp will NEVER be dead on. kind of close but never exact. don't forget, the sensor is located on the PCB, which is inside of a metal/plastic/wood case. it's essentially cut off/isolated from measuring the actual room temp. it has to make a prediction based off of case analyzers results. it's close enough for a vape board. i will say this, i would of rather seen the field labeled as "ambient board temp" rather than "room temp" for just this reason.

if your mod working fine, i wouldn't sweat the small stuff.

[dywersant]

MM22 said:

@MM22
Thanks, good to see someone else has also found this to be inaccurate.
It seems, that dna250 is reading voltages about 0,6V higher that its supposed to, and the same behavior can be replicated on different boxes.
The good thing is that it wont overcharge your cells.
Iam going to fill a report bug form today.
@ChunkyButt200
Ill charge my cells, measure them and will let You know.

[MM22]

@ChunkyButt200

Thank you so much for the answer!!

My mod isn't working fine, my mod is just working PERFECT. I love it and I still don't know how could I vape before getting my first DNA.

I knew that the ambient temp issue could be related to the case analyzer, but when I leave the whole mod overnight in a room with an exact temp, WITHOUT any cells inserted (so no current flowing) shouldn't the whole mod (and the whole PCB inside) stabilize at around the 19 °C in the room?

However, next week I'm going to have a little bit of spare time to play with the case analyzer, I'll let you know.

I have to do some funny things also, such as measuring my mod resistivity.

 

As for voltage readings... later I will charge my cells inside the mod and let you know... however I'm 99.9999% sure they'll stop charging exactly when the board reads 4.20V... but the real question is:

given that REAL 4.20V are read as 4.25/4.27 by the mod... will the 4.20V charging cutoff be @4.20V or lower?

So I'll even check my cells REAL voltage after charging and let you know!

I've never tried charging cells inside the mod... so which USB Adapter is better?

I have:
-5V@1.0 A
-5V@2.0 A
-5V@2.1 A

I know my DNA 250 can charge @2Amps, but should I give it 100mA more to run properly and charge effectively @2Amp? (NOTE: Any external charger that has a total maximum output of 2Amp, always needs at least 90-100mA of activation current, so the required input for 2Amp charging will be AT LEAST 2.1Amps... for example XTAR VC4)... So I'll probably go for the 5V@2.1A USB adapter... am I right?

Thank you!!

[VapingBad]

Yes, IMO some headroom is the USB Power supply is beneficial, so from your choices probably the 2.1 A, but you will see some voltage drop between the supply and the DNA the best I get is just over 9.5 W.  The cable makes a lot of difference and generally shorter is better, have USB power as a charging field to pick the best PSU + cable, also not charge rate will reduce if the board get hot and charge rate is limited to 1 C.

[MM22]

VapingBad said:

Yes, IMO some headroom is the USB Power supply is beneficial, so from your choices probably the 2.1 A, but you will see some voltage drop between the supply and the DNA the best I get is just over 9.5 W.  The cable makes a lot of difference and generally shorter is better, have USB power as a charging field to pick the best PSU + cable, also not charge rate will reduce if the board get hot and charge rate is limited to 1 C.

Thank you! I know that, I always use max. 10cm long cables to charge, and longer cables just for data (I set the max. USB current at 0 when I have to work with settings).