DNA 75 battery life-PLESE HELP

[ryno250]

Hi I have bought a SBODY LEGEND DNA 75...I bought the IJOY 4200mah 26650 and an efest green 4200mah 26650...Any way the IJOY is meant to be the best 26650 out...And Im getting horrible batter life Im running a 0.54 ohm coil at 34watts and at about 60-70% of battery the battery icon starts to flash and it won't fire the full 34 watts.When I check the battery on my charger it shows it is still at around  3.9volts...It is driving me mad I have run battery analyser to no avail...And have tried a few things with escribe settings...Its only drawing like 8amps from the battery and The IJOY battery is rated for 30amps(by mooch) ands should  at least do 20amps..So how come it is dropping off the power so quick???

[retird]

Have you checked the battery sag while firing in Device Monitor?

[dwcraig1]

Probably more of not getting the power to the board than a problem with the battery not being able to supply it. You might try cleaning the battery cap threads with alcohol or such.

[ryno250]

Hi yes have checked for battery sag...and depending on the level of charge how far it drops, but when this prob starts happening sags to about 2.75 volts...Yes ill try cleaning the battery cap threads, however the mod is brand new, only 1 week old....Yes thats what i felt the power isn't getting to the board..

[dwcraig1]

Sorry but I don't know how they achieved the B- connection between the battery and board but it can be done in a few ways.
one way it the three mounting screws that mount the board into the case, screws might be loose.
Another way is by using the output ground to the 510 connector, the 510's ground wire would also provide ground for the board. So if the 510 housing it not well grounded to the case then the board won't be either.
A DNA 75 can be wired using only two wires, B+ and  Out (to 510), the three board screws to metal case can provide all grounds when all is solid.

[ryno250]

ok yes I ouldnt know where to start at pulling this apart there is only four screw I can see and they are those star type screw heads not alum,phillips or flat shaped like a star..two on top next 510..and two on bottom either side of battery cap...What sort of performance should I be expectring from a single 26650.....at 34watts at 0.54 ohms should I be able to go till the battery is flat as I'm only making it to 40% max......I had an evic mini and it performed better than this..Such a shame for such an expensive mod...

[dwcraig1]

I can only guess but here it is:
At 34 watts I would think you should be able to drain the cell down to 3.2 - 3.3 standing voltage before you start hitting the 2.75 volt cell soft cutoff, maybe even lower.

[ryno250]

yes standing voltage is only 3.9volts...I thought it was weird and very high compare o what ive experienced with my other mods....Don't know what to do??

[dwcraig1]

If possible return to where you got it. I understand that that may not be all that easy.

[giz_60]

There have been issues with other devices that utilize the same type of battery setup as yours, screw on cap on the bottom, where the ground is transferred to the board via the device case & loose board mount screws are causing problems...


 

[ryno250]

So basically I have to get the screws tightened on the board some how...Is it hard to get one of this star tools..Just at my local hard ware s tore or something???

[dwcraig1]

The name is Torx, make sure if a set it goes small enough.
Just an example:
http://www.harborfreight.com/32-piece-screwdriver-set-with-tweezers-97517.html
 

[ryno250]

ok thank you ill chase sum up n see what I can find out..DO you know about what size tore i need ,,I've been looking them up i can get a set of T3 to T6 will T3 be small enough or do i need a T1 or T2...thanks

[ryno250]

I orderd a torx set today should be here by the end of the week got one with sizes T2-T15 so hope T2 is small enough ..

[ryno250]

Ok got the set today ,pulled it apart and tightened al the screws the were a lil loose, and so were the body screws, and the screws that hold down the positive contact were also loose,It might be me but it seems to be hitting much harder now,I was set a 26watts but seem to be getting about the same at 20 watts ,is that possible..

[giz_60]

You betcha...better connectivity, better performance....

[dwcraig1]

Device Monitor in Escribe will show you the answer.....tell us too.

[ryno250]

What specifically  should i be looking for in device monitor...???

[giz_60]

Improvements over the last time you ran Device Monitor...less battery sag, etc...

[ryno250]

ok cool,I was thinking battery sag,I will have a look today when i get a chance

[ryno250]

yes went into device monitor,voltage isn't dropping as far as it was at a full bater it dropping to 3.89 insead of like 3.7 so bit beter