voltage drop explained?

[beazy]

I dont know if I'm doing this right or not..
Using an aw imr 18650

Battery: 4.04v

Nemclone shows 4.04v (no drop)
Richman Atty with .8 ohm coil
Volts under load: 3.20

Looks pretty huge...

Divide 4.04 by .8 to show 5.05 amps then multiply by .8 which takes me back to 4.04.. Multiply by 5.05 to give 20.4 watts.

Did I do this right? And does this mean I have no drop in this mod? Please forgive my bay county education. I am confus.

 

[Kemosabe]

just use an ohms law calculator. there are website and app versions. the app is called Ohms Law- its handy to have on your phone/tablet. another one which also includes some handy DIY and rba stuff is called iVape. both are free.

for the computer, try this: Ohm's Law Calculator

and to answer your question, yes you have 0.00v drop without load, which is quite common these days. your voltage under load was determined by you to be 3.2

 

[beazy]

just use an ohms law calculator. there are website and app versions. the app is called Ohms Law- its handy to have on your phone/tablet. another one which also includes some handy DIY and rba stuff is called iVape. both are free.

for the computer, try this: Ohm's Law Calculator

and to answer your question, yes you have 0.00v drop without load, which is quite common these days. your voltage under load was determined by you to be 3.2

Ok so I'm haveing trouble understanding how to calculate the 3.2 under load for the drop

 

[beazy]

I feel like this is a topic that has to have been delved into thoroughly by this point..If anyone can point to that discussion iI'll gladly ungunk the boards of this post

 

[CloudZ]

For the "volts under load", are you measuring voltage parallel to the atty posts? If so, your voltage drop is 0.84 V, which is quite high for 0.8 ohms. Make sure everything is clean and well connected and try again.

 

[Thrasher]

usually V drop depends on the battery VS resistance VS the atty itself. with something this high i would do some testing.

I would test the atty center pin.from top to 510, then just the coil at the screws. then test the coil/atty at the 510 connector, then test couple parts of the atty with no coils attached then again while screwed on the mod. something is not right somewhere as like stated .8 is huge.

and make sure the 510 threads on the atty and mod are good and clean

 

[DaveP]

The voltage drop is there because the battery can't continuously produce its rated capacity under that kind of load. Internal resistance plays into the result you get when you stress a battery or any power source.

You see the same type of result when the wiring for a 120v outlet is loaded beyond the capacity of wiring that is too small to carry the load. The result is an increase in internal heat dissipated by the delivery device whether it's wiring or in the chemistry of the battery. Electrons can't flow fast enough to satisfy the load.

 

[beazy]

i pulled the atty apart and cleaned everything, it went up to 3.52

 

[John_]

Energy is lost when current travels across anything that has a resistance, most often you will notice this as heat (wires will heat up given enough time/power). This is what we call "voltage drop." Most high end mech mods have extremely low resistances so you will see a very little voltage drop (almost unnoticeable). With an atomizer that has coils, you're introducing a significant resistance so the energy you're getting will drop a more noticeable amount.

 

[st0nedpenguin]

The voltage drop is there because the battery can't continuously produce its rated capacity under that kind of load. Internal resistance plays into the result you get when you stress a battery or any power source.

You see the same type of result when the wiring for a 120v outlet is loaded beyond the capacity of wiring that is too small to carry the load. The result is an increase in internal heat dissipated by the delivery device whether it's wiring or in the chemistry of the battery. Electrons can't flow fast enough to satisfy the load.

While true, a loaded voltage of 3.2v with a .8ohm coil is pretty low.

Are you using the 1600 or 2000 AWs beazy? And how old are they?

 

[Rule62]

A pretty good primer about voltage drop. It was posted on Atmizoo's site about a year ago.
Voltage Drop - Where and Why | atmizoo vaping modware

 

[DaveP]

While true, a loaded voltage of 3.2v with a .8ohm coil is pretty low.

Are you using the 1600 or 2000 AWs beazy? And how old are they?

Could be an old battery or just a buildup of resistive tolerances in the chain of components. You are right that .8 ohms isn't a heavy load and shouldn't drop that much on a fully charged battery. Right now, I have a Kanger PT 1.2 ohm coil on my Provari. Right off the charger, my year and a half old AW 18650 2000mah lMRs read 4.2v then immediately drop to 4.0v when I do the internal loaded voltage test. His shouldn't be dropping like they are.

I'm betting on fatigued batts.

 

[CloudZ]

i pulled the atty apart and cleaned everything, it went up to 3.52

That's a nice improvement. The rest of the drop beyond -0.3 V could be from the age of the battery, any residual oxidation or oils/juice residue on the connections including the body threads, coil connections, or measuring equipment. I wouldn't worry about it too much unless you really want to reduce the drop as much as possible, especially if the vape is good now.

 

[DaveP]

Batteries charged and measured right off the charger will drop almost immediately to 4.0 and then 3.9 with the first puff or two. They'll stay in the range of 3.6 to 3.8 for quite a while before an accelerated drop toward the 3.2 to 3.5 levels. Testing under load vs just measuring with a voltmeter and no load will produce different numbers, FWIW.

Noalox or Ox-Guard on the battery tube threads will give you measurable performance improvements over dry threads that may be slightly oxidized. Those compounds also reduce thread wear and extend the life of the mod.

Once you cure the resistive components of the chain of conduction, then you can look at battery age and its ability to maintain loads during discharge. Comparing to a new battery might reveal where the problem lies. 3.5v on a new battery under load once circuit resistance has been verified still indicates a weak cell. I generally charge at 3.5v after vaping all day on the battery.

 

[Bunnykiller]

Ok so I'm haveing trouble understanding how to calculate the 3.2 under load for the drop

no load V = 4.4 with load = 3.2 4.4/.8 = 5.ish 3.2VX5.ishA = Watts eg 15.ish watts just a ruff estimate my calculator batteries died last nite.

 

[beazy]

They are 2000mah. They are about 3 months old and get charged once a day at least. I cycle through 3 a day sometimes just 2 if I'm busy