Can ohms be too high?

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Eddie.Willers

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When you do, please clue me in. I just can't grasp that technical stuff. ;)

Try not to get too hung up on the whole ohms vs. volts thing - they are just the measurements we need to calculate what matters, WATTS.

'Watts' is a measure of energy conversion - in our case from electrical (battery) to heat (atomizer/cartomizer coil).
Put simply, the more watts your heating coil consumes to do its job, the less time the battery charge will last.

Watts are calculated by multiplying the voltage (at the coil by itself) (squaring) and dividing by the coil resistance.

So, Provari set to 4.5 volts with a Boge 2 ohm carto - 10 watts of power being used. (4.5x4.5 = 20.25 volts then 20.25/2 = 10.1 watts)
4.2 volts with a 1.7 ohm carto = 10.4 watts
5 volts with a 1.7 ohm carto = 14.7 watts etc.

For practical purposes, this means that a VV device will be able to use a wide range of carto resistances but still keep the watts (the rate of heat output) close to what you prefer.
:vapor:
 

BuzzKill

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ohms/volts/current are mutually relative !! Ya I KNOW ,

OK increase the OHMS = lower Current and power at the same voltage , reduce the ohms and ??? yep the opposite happens

OK increase the voltage = Increase current and power , reduce and! !!

OK Increase the current = Increase power and voltage ( or reduce resistance ! )

We deal with Variable voltage so the current and power are varied by the voltage ( the res. is normally fixed ) so increase Volts and increase current and power.
when you change res. this changes both the parts.

Or just use this and shoot for a certain POWER Ohm's Law Calculator

Enter the resistance and voltage to get the power ! ( I use 4.5 volts as a base line )

EDDIE got it right !
 

BuzzKill

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Thanks Eddie and buzzkill. I still don't quite understand it all but that's ok ;-)

Why do some shy away from a PV that has stacked batteries? It seems to me 2 3.7v batteries stand a better chance if producing stable watts then one 3.7v battery?

It has to do with the controller design , we use what is called a BUCK regulator/controller , these REDUCE the voltage from a higher voltage ( they convert voltage into current ) , they tend to be the MOST efficient design to conserve current ( a battery stores current ) .

A BOOST regulator takes a lower voltage ( like 3.7 v ) and BOOSTS it up to the higher voltage , a boost reg. convert current into voltage so they require a large high capacity battery to operate like a 18650 High Drain battery.

I hope this helps some ?
 

caged

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Some also think the coils higher resistance attys have more surface area that turns juice in to vapor.

Yes thanks, that makes perfect sense. I guess I'm just stating the obvious when saying 2 3.7v batteries in series should have a better chance of maintaining constant volts/amps/watts than one 3.7v battery. Thus my question "Why do some shy away from a PV that has stacked batteries?"

It's the latest fad. Some think dual batteries are more dangerous because there have been a few incidents of second rate batteries exploding in second rate mods with no protection circuitry. The reality is I have seen more single battery mods have issues with batteries, including single IMR batteries in a Provari. The people who are worried about stacked batteries ignore the fact that the lighters they used to carry in their pockets with no problem when they smoked are more dangerous.

You gotta love the media.
 
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