Ohm/Amp/Watts

[HauntedMyst]

Does anyone have a reference of an Ohm/Watts scale? Is there one?

For example

Does a 1 ohm at 10 watts roughly equal to 2 ohms at 20 watts? Is there any sort of equivalency vapor wise or am I imagining one where it doesn't exist?

 

[Ablonz]

Here is a link to a calculator for finding out wattage. Ohm's Law Calculator if you enter in 2 of the variables, you will get the rest. I have tried what you were looking for and 1 ohm at 3.3 volts is 10.89 watts. Running a 2 ohm coil at the same voltage 3.3 would only give you 5.44 watts. Where as 4.65 volts on a 2 ohm coil will give about the same wattage as a 1 ohm coil with 3.3 volts. Hope this helps.

 

[Baditude]

A couple of years ago there was a Safe Vaping Power Chart that dealt with voltage/wattage/resistance (ohms), however it was fabricated with cartomizer use in mind. That chart may or may not apply in this day and age.

I don't own a device that uses variable wattage, only variable voltage. In the early days I used the Ohms Plus "2" Formula to set my device's voltage. You simply take the coil's resistance rating and add the number "2"; the sum will be a general startoff point to set the voltage. [2 ohms + 2 = 4 volts.]

 

[HauntedMyst]

Thanks guys!

 

[Katya]

Does anyone have a reference of an Ohm/Watts scale? Is there one?

For example

Does a 1 ohm at 10 watts roughly equal to 2 ohms at 20 watts? Is there any sort of equivalency vapor wise or am I imagining one where it doesn't exist?

1Ω coil on at 10 watts will give you the same power output as a 2Ω coils at 10 watts--your battery does the math for you. In other words, if you're in wattage mode and set your battery to 10 watts, you'll always get 10 watts, no matter what resistance coil you'll attach to said battery. It's a completely different situation if you're in voltage mod--you have to figure out the wattage you want.

Maybe this will help:

Disclaimer: This is the most simplistic explanation and is addressed to new vapers or vapers who are happy within the recommended "just right" power zone (4.5-8 watts) and use stock coils.

Ohm's Law as it pertains to vaping is really not that complicated--and it's very useful when you want to know what you're doing.

Voltage and wattage are often misunderstood by new vapers. Wattage is the power (heat, sweet spot) that your PV (battery and atomizer) generates. Wattage = Voltage (of your battery) squared divided by Resistance (Ω) of your atomizer [P=V[SUP]2[/SUP]/R]. If you're not good at math, don't worry, use this easy calculator:

Online Conversion - Ohm's Law Calculator

Of course, if you own a VW (variable wattage) device, you don't really need this calculator because your device will do the math for you.

The wattage you want, especially at the beginning of your vaping career, should be somewhere between 4.5 and 8.5 watts per coil. Anything lower than 4.5 watts may not vaporize your juice properly and will not produce enough warmth and vapor. Anything above 8.5 watts increases the risk of burning the filler in your cartomizers (if you're using them) or dry with your clearomizers.

There are, of course, other variables, like eliquid and JDD (juice delivery devices) that you're using on your batteries. Seven watts on a filler type cartomizer may feel different than the same 7 watts on a fillerless clearomizer or a dripping atomizer. The same is true for different eliquids; tobaccos, chocolate and coffees generally require more wattage (heat), while fruit and other delicate flavors do better with less heat. Everyone's sweet spot is different--those are just very general guidelines.

If you are using dual coil atomizers, things get a bit more confusing. Dual coil atties consist of two coils configured in parallel, which means that a 2.1Ω atty is really two 4.2Ω coils--so you have to calculate your wattage based on the 4.2Ω number--not 2.1Ω--roughly. Dual coil atties require more wattage than singles, but not quite twice as much. They produce more vapor due to increased surface. I usually increase the power (wattage) by ~50% when using dual coils; for example, if I like 6 watts with a single coil atty, I start at 8-9 watts with a dual coil atty. That's just my preference--YMMV. When in doubt--start low and adjust up as needed.

If you are interested in high wattage (and/or sub-ohm)vaping, that's a different conversation altogether--and not my area of expertise.

Experiment and you'll find your own bliss in no time!

The chart below is a good guide to safe vaping, even though some think it's a bit conservative.

 

[Katya]

I don't own a device that uses variable wattage, only variable voltage. In the early days I used the Ohms Plus "2" Formula to set my device's voltage. You simply take the coil's resistance rating and add the number "2"; the sum will be a general startoff point to set the voltage. [2 ohms + 2 = 4 volts.]

For some weird reason, this method always takes you to 8 watts.

Which may not be ideal--it may be too much oomph for low wattage, single stock coil users, and certainly not enough for people who use dual coil atties. I always use the online calculator.

Heya Bad! Nice to see you again.

 

[bwh79]

Amps = Volts/Ohms. This isn't just a good idea, it's the law.

Also:
Volts = Amps*Ohms
Ohms = Volts/Amps

These are just different ways of stating the same relationship. Volts, Ohms, and Amps are all related to each other in that if you change one of them, one or more of the rest has to change as well to balance it out. Power (wattage) is another related quantity, which can be calculated as:
Watts = Volts*Amps, or
Watts = Volts²/Ohms

Watts represent the amount of power that is being delivered to the atomizer. It's essentially how much "energy" is available to vaporize the juice. The vape experience is affected by this raw amount of power, but also by other factors like the length and thickness of the wire you use (which also, indirectly, affect the resistance.) You can get 25 watts from a 1-ohm coil at 5 volts, for example, or you can get the same 25 watts from a 0.5-ohm coil at 3.5 volts, but they won't vape the same, even though the power is the same.

 

[ignotus]

You can get 25 watts from a 1-ohm coil at 5 volts, for example, or you can get the same 25 watts from a 0.5-ohm coil at 3.5 volts, but they won't vape the same, even though the power is the same.

Very true. I've noticed an inverse relationship between resistance and wattage in my own vaping: as one goes down, the other goes up and vice versa. It's the voltage that remains stable at around 4.4.

 

[Ryedan]

Does anyone have a reference of an Ohm/Watts scale? Is there one?

For example

Does a 1 ohm at 10 watts roughly equal to 2 ohms at 20 watts? Is there any sort of equivalency vapor wise or am I imagining one where it doesn't exist?

Full disclosure: Katya said it first (but I was going to if she didn't

):

"1Ω coil on at 10 watts will give you the same power output as a 2Ω coils at 10 watts--your battery does the math for you. In other words, if you're in wattage mode and set your battery to 10 watts, you'll always get 10 watts, no matter what resistance coil you'll attach to said battery. It's a completely different situation if you're in voltage mod--you have to figure out the wattage you want."

So watts is power, or the amount of heat you put into the atty. This is what (no pun intended ) has a huge influence on your vape experience. Watts have no direct influence on vape temperature, that's much more influenced by coil surface area and atty air flow.

Consider a water kettle. If your kettle puts out 500 watts it will take a while to boil the water and then the water will not boil that much. Now consider a 2,000 watt kettle. That monster will boil the water fast and when it boils, well it will boil fast. The water temperature OTOH will stay at 212 deg F.

With single coil clearos and cartos, the old resistance in ohms plus 2 rule of thumb is a good start in volts to a reasonable setting. With dual coils in anything, or with rebuildable attys, that goes out the window. And don't forget, it's really the watts that rule here.

And even thinking watts, it all depends on the build you have with the hardware you have. I have RDA's that are overpowered at 13 watts and some that are underpowered at 25 watts no mater how I set them up.

Air flow, atty design, wicking, wire gauge and power applied all work together to make things work the way they do. The Steam Engine coil building calculator is a very good aid in getting this stuff right and I use that whenever I design a new atty build.

Works for me, but I'm a bit of a nerd and I like the techie side

 

[edyle]

Does anyone have a reference of an Ohm/Watts scale? Is there one?

For example

Does a 1 ohm at 10 watts roughly equal to 2 ohms at 20 watts? Is there any sort of equivalency vapor wise or am I imagining one where it doesn't exist?

You have to account for wire gauge.

But if you compare with the same gauge wire
a 1 ohm single coil at 10 watts should run at the same temperature as a 2 ohm single coil at 20 watts.

 

[Ryedan]

For some weird reason, this method always takes you to 8 watts.

Yes it does, as it is designed to do for single coil clearos

 

[Katya]

Yes it does, as it is designed to do for single coil clearos

Isn't that odd, though?

And FYI--I like 6.5-7 watts.

So sue me.

 

[TaketheRedPill]

Here's a down and dirty calculator. Enter any two values. To change values and play around, just x out the current value and type in a new one (you'll see what I mean when you tap=select a box)

Watts - volts - amps - ohms conversion calculator

 

[bwh79]

Isn't that odd, though?

Not really. It's just (x+2)²/x. It is merely a coincidence that we just happen to use resistances (values of x) that are right near where the function bottoms out at f(2)=8. Get very far from 2Ω though, in either direction, and the power stops being "right around 8 watts" pretty fast:

 

[Katya]

Not really. It's just (x+2)²/x. It is merely a coincidence that we just happen to use resistances (values of x) that are right near where the function bottoms out at f(2)=8. Get very far from 2Ω though, in either direction, and the power stops being "right around 8 watts" pretty fast:

I love math.

And yes, it's still odd (amusing, funny) that we just happen to use resistances that are right near where the function bottoms out at f(2)=8.

 

[edyle]

I love math.

And yes, it's still odd (amusing, funny) that we just happen to use resistances that are right near where the function bottoms out at f(2)=8.

it's a crude way of doing your own vw when all you have is a vv.

 

[soysos]

volts are a measure of electrical potential, or the amount of energy the cell is capable of discharging at a given time. ohms are a measure of electrical resistance, how much your coil will resist that energy. amps are a measure of current, is being discharged from the cell. watts are a measure of electrical power, the overall energy usage of the coil.

with all this in mind there really is no need to use a fancy calculator. amps=V/O watts=AxV