Volts or watts?

[Zutankhamun]

I should know by now but I don't. I forget but if I build + 1 ohm I can fire 50 watts but still get 7.5 volts. If I was to build low on a regulated device it would take a lot more watts to get the same volts. The vape feels nearly the same. Are the volts the final variable on how hot my coils get? If it is not a mech, then watts don't matter so much. Only volts. Is that right?

 

[MMcQ]

You've got it backward. Watts are what matters. Lower ohm coils need more watts as they are typically composed of larger diameter wire and require more energy to heat up but a low ohm coil built with higher gauge wire would heat up faster with less voltage so lower watts. What really matters is wicking and surface area.

 

[edyle]

I should know by now but I don't. I forget but if I build + 1 ohm I can fire 50 watts but still get 7.5 volts. If I was to build low on a regulated device it would take a lot more watts to get the same volts. The vape feels nearly the same. Are the volts the final variable on how hot my coils get? If it is not a mech, then watts don't matter so much. Only volts. Is that right?

1: "Are the volts the final variable on how hot my coils get?"
No.
2: " If it is not a mech, then watts don't matter so much. Only volts. Is that right?"
No.

watts = volts x volts / ohms.

thicker wire needs more watts to get hot.

 

[Zutankhamun]

Okay thanks. So would I get more vapour on a high ohm or low ohm build with the same gauge wire? If in both cases the device was pushed to the limit with the same dripper? The thickness would be the same but I would need more heat for more metal in the higher build? Just trying to understand any benefit in running low builds on my regulated devices. Thanks

 

[suprtrkr]

Assuming the same coil, volts and watts are the opposite side of the same coin. Watts = Volts^2/Ohms, and Volts = Sqrt(Watts x Ohms). If the coil stays the same, you can't change one without changing the other.

 

[Zutankhamun]

Thanks but why ever build low if you are not using a mech? It takes longer to heat up so more battery use and also unnecessary strain on the battery. Are there any upshots?

 

[suprtrkr]

Thanks but why ever build low if you are not using a mech? It takes longer to heat up so more battery use and also unnecessary strain on the battery. Are there any upshots?

In general, the advantage of building low allows you to put more watts on the coil. It isn't low builds that call for high ramp time, but rather coil mass. They are usually the same in practice because low builds use thicker wires, but there are ways around it, primarily by increasing the surface area of the wire.

 

[MMcQ]

clouds bro! <sarcasm included>

 

[Flt Simulation]

What effects how much total heat a particular coil gives off .....

This may be a little oversimplified, but here is how I understand how much [total heat] any single coil will produce at a given time:

Heat Flux: Basically how hot the coil gets. As voltage is increased on a coil, Heat Flux obviously increases.

Coil Surface Area: Amount of the coil area that is being heated. Larger the area, the more the total heat.

Both Heat Flux and Coil Surface Area [in combination] will determine exactly how much total heat a particular coil will produce at any given time.

1. If you have 2 coils that have the same amount of Coil Surface Area, the coil that is powered up to the highest Heat Flux will give off the most amount of total heat.

2. If you have 2 coils that have the same amount of Heat Flux, the coil with the greatest amount of Coil Surface Area will obviously give off the most amount of total heat.

Now, lets say you have a coil with a Heat Flux of 100 mW/mm² and a Coil Surface Area of 100mm², it will give off the same amount of total heat that a coil that has a Heat Flux of 200, but only a Coil Surface Area of only 50mm²

Likewise, a coil with a Heat Flux of 200 would only need a Coil Surface Area of 50mm² to give off the same amount of total heat as a coil with a Heat Flux of 100, and a Coil Surface Area of 100mm²

The greatest amount of total heat produced by a coil would be a coil that not only has a large Coil Surface Area, but also one that has a high Heat Flux ... of course it takes a lot of power to attain a high Heat Flux on a large Coil Surface Area.

Really, it's pretty simple ... both Heat Flux and the Coil Surface Area work in combination to determine the total heat a coil produces.
________________________________

And here is where you can input your particular coil info and find out how much Heat Flux and Coil Surface Area you will have. Make sure you click the "Advanced" button to see your Coil Surface Area.

Also input the watts of power you are applying to your coil in order to get the correct Heat Flux. (the default is 10 watts, so just change it to whatever you want to apply to your coil)

Link: Coil wrapping

 

[WharfRat1976]

I should know by now but I don't. I forget but if I build + 1 ohm I can fire 50 watts but still get 7.5 volts. If I was to build low on a regulated device it would take a lot more watts to get the same volts. The vape feels nearly the same. Are the volts the final variable on how hot my coils get? If it is not a mech, then watts don't matter so much. Only volts. Is that right?

E=mc°

 

[Inni]

You've got it backward. Watts are what matters. Lower ohm coils need more watts as they are typically composed of larger diameter wire and require more energy to heat up but a low ohm coil built with higher gauge wire would heat up faster with less voltage so lower watts. What really matters is wicking and surface area.

LOL

I'm very impressed, and equally confused. I will never be able to build my own anything.

I am quite curious about the volts vs watts thing - so I will keep reading........

 

[MMcQ]

LOL

I'm very impressed, and equally confused. I will never be able to build my own anything.

I am quite curious about the volts vs watts thing - so I will keep reading........

Perhaps I should clarify this. With an unregulated mod the only way to increase your watts was to build a lower ohm coil as voltage is fixed. With a regulated mod the resistance of the coil is irrelevant in terms of figuring out your watts because the mod does that for you. Voltage is just a part of the wattage equation. You could manually just raise your volts in a regulated mod (if it offers the option) but the effect is that you are still raising your watts. That said, higher watts does not necessarily equal better vape.

 

[mcclintock]

Okay thanks. So would I get more vapour on a high ohm or low ohm build with the same gauge wire? If in both cases the device was pushed to the limit with the same dripper? The thickness would be the same but I would need more heat for more metal in the higher build? Just trying to understand any benefit in running low builds on my regulated devices. Thanks

If you wrap the same wire more times, the coil is bigger, that's simple. It is suitable for more power and vapor production. Contrary to the idea of low ohms is high power, it's also higher resistance. To make a lower resistance, larger coil would require thicker wire.

I carefully said it's "suitable" for more power and vapor production because that's limited by at least 3 factors: airflow, wicking, and coil area. If the coil isn't big enough there's no chance. If the wicking can't keep up, then the coil overheats anyway. If you don't want to pull a lot of air through it, even a large coil and wick will get too hot (at least too hot a vape, it might not burn the juice). The best vape will have these items in proportion, making one bigger will reduce the quality.

A longer, thinner wire has less mass for its surface area than a shorter, thicker one and will heat quicker. However, most cases of real slow heat up are underpowered coils. Thin wire is more delicate especially when wound into a long coil. There could even be issues of getting it to fit in the atty.

 

[edyle]

Okay thanks. So would I get more vapour on a high ohm or low ohm build with the same gauge wire? If in both cases the device was pushed to the limit with the same dripper? The thickness would be the same but I would need more heat for more metal in the higher build? Just trying to understand any benefit in running low builds on my regulated devices. Thanks

Yes, with the same gauge wire, the higher ohm single coil will need more voltage and watts and produce more vapour.

 

[edyle]

Thanks but why ever build low if you are not using a mech? It takes longer to heat up so more battery use and also unnecessary strain on the battery. Are there any upshots?

When you want more power you either add more coils or use thicker wire.
Either way makes your ohms drop fast.

When you use a regulated mod, you should check steam-engine.org and look under 'mod range', and check for the optimal ohm range for your mod. The optimal ohms is the value of ohms where the mod's full wattage range is available.

 

[WharfRat1976]

When you want more power you either add more coils or use thicker wire.
Either way makes your ohms drop fast.

When you use a regulated mod, you should check steam-engine.org and look under 'mod range', and check for the optimal ohm range for your mod. The optimal ohms is the value of ohms where the mod's full wattage range is available.