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dwcraig1

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Reply with quote  #16 
It looks to me as you are hitting the soft cell cut off, either battery, battery connection or both aren't cutting it. Sag under load looks excessive.
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dwcraig1

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Reply with quote  #17 
here's a screen of my vt133 firing @ 65 watts. cells is are about 4.1 volts unloaded, 3.69 volts loaded. They are Samsung 25r's
vt133.JPG 


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Evo1340

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Reply with quote  #18 
ok, I'm still waiting on the new batts to fully charge. Then I'll see how it goes with those. I have been using LG HE4's mostly but have some Samsung 25r's to try now. I'm not one who builds extreme low ohm coils so I don't often use my LG HB6's which are a true 30amp battery. I'll keep looking to see if there are any settings for voltage step down. Thanks
dwcraig1

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Reply with quote  #19 
I suspect your problem to be with the battery sled contacts, you will soon see. HE2, HE4, 25r's....all good
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Evo1340

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Reply with quote  #20 
Yah I just put the new 25r's in and it's much improved. A lot less sag so far. We'll see how it goes as they drain. I can't see anything going on with the contacts.
dwcraig1

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Reply with quote  #21 
Quote:
Originally Posted by Evo1340
Yah I just put the new 25r's in and it's much improved. A lot less sag so far. We'll see how it goes as they drain. I can't see anything going on with the contacts.
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VapingBad

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Reply with quote  #22 
You may to lower your soft cell cut off for 18650s to 2.75 V, it's the voltage under load so don't worry that it will over-discharge them it won't.
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Latest versions of EScribe: DNA 200/250DNA 75
Common problems
Evo1340

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Reply with quote  #23 
ok I'll check it out. I set it at a random 3.02 last night.
Asmodeus

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Reply with quote  #24 
I'm in the same boat.  I came from a v1.5 minikin that will fire just about anything so long as it's .08Ω or higher.  You can watch the battery meters sag horrendously when you are north of 100W and firing things that low.  But it WOULD fire without a change in the vape the whole way down until the batteries were down to about 3.2-3.3v IIRC.  

When I set up the DNA250/167.  I set the cut off around 3.2V and all was OK for a little while.  I noticed I was not able to run the batteries out as far and at times I would get a hesitation in power.  I thought perhaps it was just not reporting correctly and they were really low.  So I set the cut off to 3.5v.  It got worse.  When I put the batteries in the charger they were still showing 3.7v.  

Wait a damn second...

I then realized what a SOFT cut off was.  It wasn't a discharge limit.  And I was slamming into it when the batteries sag.  Mine sag just as hard.  I have 16ga silicone wires feeding the board and 14ga for the output.  I have LG's, Samsungs, and Sony's... and it makes no difference which ones are in there.  I have 12 brand new pairs and some older ones and again, there is absolutely no difference.  They all sag .6v. +/- .1v 


My question is where is my safety issue with voltage under load?  If I want to vape the batteries down to the built in discharge limit.  How low can I go?  The board, and battery sled are taped and epoxied into the case at this point.  It is, what it is, and I have lots of batteries.  

Is there a voltage under load threshold that I do not want to cross? 


The minikin v1.5 seemed to allow for the sag and just kept thumping away.  Those batteries compared to new ones, even after being used for months like that.  Honestly show no appreciable difference in life.  I have a lot, and they are mated sets, and I rotate through them evenly.  I am down to 2.7v in the soft cut limit and I still cannot empty a set of batteries before the DNA's voltage nanny steps in and annoys me to no end.  I have the watt/hrs set lower than the recommended capacity for the batteries that I am using to boot.  

I really want to drop it to 2.5v or lower. (Which I think was the original setting when I switched to 2 battery mode in escribe)  But I don't want to destroy batteries or blow myself up.  If my sag is about .6v then I need it that much lower than the resting discharge limit.  

Is there any danger? 
Evo1340

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Reply with quote  #25 
I have to admit I'm very limited in my understanding of battery capacity v load limits v discharge rates v soft cut off v why women think the way they do. My brain wants to shut down when it comes to math for some reason. I just don't quite understand why they put such a steep auto step down in the board.
dwcraig1

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Reply with quote  #26 
I guess I might as well through this in.
The DNA200 has a hard cell cut off of 2.85 volts unless that changed with firmware update, I don't know but doubt it.
Probably the 250 is the same in regards to cut off, again I don't know for sure.
The 200/250 was designed to operate with a LiPo pack not round cells (18650, ect.) hence the higher soft/hard cutoff.
18650's, ect have their mah capacity measured between 2.5 - 4.2 volts, a lipo shouldn't be drained down that low.
So when you use 18650's, ect. with a board designed for a LiPo pack so the capacity of the round cell between 2.5 and 2.85 volts is not usable.
I set my round cell powered 200's 12% lower than what the calculator comes up with.
A firmware update listing the round cells would be an option but for sure folks would be using it with a Lipo and that could end up being a safety issue. Call every thing here "just my opinion"

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Asmodeus

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Reply with quote  #27 
I'm kinda seeing it like this... 

1.  The minikin v1.5 for $60 can nearly do what a DNA 167 can do.  It's less BS, and has a better form factor.  It suffers only in that the temp control is jerky, and my 510 loosened and I had to tighten it.  

2.  Conversely the DNA's temp control is buttery smooth.  The initial battery setup and black sheeping of 18650 users leaves a lot to be desired.  In fact the discharge profiles, and single meter is inherently poor by today's standards.  The screen also leaves a lot on the table information/vs space wise.  It's level of configuration that balances it out.  

But even building it all myself I have north of $130 in it.  And these battery profiles and watt hours are inherently flawed in a device with replaceable batteries.  Give me an option to set the meter to resting battery voltage and avoid that tangled mess.  I have many different kinds of 18650 batteries.  Both in age and type.  I realize that the 18650 set up is an afterthought, but it exists.  The baby is in the crib so to speak.  So now that we are here, you gotta deal with it.  And the way it is being crippled with 3S LiPo settings sucks.  

Two %'s would work.  Stick the meter(s) to resting cell voltage.  Watching it sag wouldn't hurt my feelings.  And when I switch from 30Q's to VTC's I wouldn't need a friggin laptop... 

The DNA on 18650's is a Ferrari with a broken gas gauge.  I don't need 250W's.  But I would like my battery meter to work with whatever I pop in it... 

As of this very moment there are multiple threads about people hitting the soft cut limit on battery sag and not knowing what is causing the mod to not fire properly.  


How low can I go on the soft cut limit?
Evo1340

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Reply with quote  #28 
I guess for me the bottom line to a DNA mod is that it's a luxury item/toy to play with and doesn't have alot to do with keeping me off of tobacco anyway. I have 4 DNA mods but 1 is still new in the box which would be the Triade DNA 250. I still like them and I'll keep messing with them I reckon. But like you say, You can get a satisfying vape from a $40.00 - $60.00 mod just as easily.
VapingBad

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Reply with quote  #29 
You really don't "need" to set up the battery curve or capacity, they don't affect anything other than the battery metre.  It is one of those untrue truisms that pervades the vapesphere that these needs to be done, I have been using the default curve in my rolo for well over a year now.  Same goes for case analyser and mod resistance they are beneficial, but not essential and in an ideal world they would be set correctly by the manufacture.  Though if you are at ultra low res of very high power I do suggest you set your mod res.
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• I am not employed by nor do I represent Evolv Inc.  All opinions are my own, they are just opinion not fact and can be wrong •

Latest versions of EScribe: DNA 200/250DNA 75
Common problems
Asmodeus

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Reply with quote  #30 
Quote:
Originally Posted by VapingBad
You really don't "need" to set up the battery curve or capacity, they don't affect anything other than the battery metre.  


I don't "NEED" a gas gauge in my car either.  I can just do my best to feel when the tank is getting low from the way the car handles a good bend at speed.

But I deserve a functional one.  One that doesn't care if I fill up at Sunoco, BP, Exxon, or perhaps even spike the tank with toluene.   

Tying the meter to battery voltage solves the problem in the simplest way possible.  Set a simple voltage scale stretching between 4.2v and the discharge limit and let me select that instead.  Two little bars a few pixels wide would go a long way to nudge the DNA up to the standard that we should expect from a chip these days.  The chip alone costs more than a functional mod with these features.  


We shouldn't make excuses for mediocracy.  In their quest to make an ultra customizable battery meter for LiPo's the simple solution for 18650's was entirely neglected.     
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