Don't forget about Watts Law
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They are already regulatedTo late
I am amazed there is not a petition to Ban Regulated mods at this point.
An outright ban is the next logical step.
Watts is not a variable in ohms law, I'm not sure how many times I have to clarify this, please point out where it references power.
Emits
Creates
Consumes
Temperature
Heat
Hot
Surface temp
All these words placed incorrectly change the entire meaning of the discussion.
All strongly related.
None synonymous or interchangeable in this context.
Pesky little .......s.
Tapatyped
Consider that not 1 yr ago, simply putting cells in series was KNOWN to IMMEDIATELY result in explosion, loss of face, fingers, life and house.sorry for the off topic.the heli remark wasnt meant at anyone.I love my 500 size it gets the most flying time
I mean no disrespecr to anyone but my comment just meant that we have a 7 page thread about watts on a 1 or 2 cell system.....again no disrespect meant but if we were dealing with a 12 cell series set up,this thread might never end
We're making SERIOUS progress.
Honestly
Tapatyped
Higher resistance requires more voltage to push the same amount of power. In the famous water analogy, Voltage is how much height of water is pressing down, Current is how much water moves. Both are needed to make power flow, to actually do anything.
Each of those coils produce the same heat. It's not just current. But see the next...
The biggest factor in making coils that are most comparable is getting the same surface area -- in this comparison it's the mod's job to feed them the same power despite the different resistance. To do this, the wire lengths can not be the same, vs. what you say you did. The lower resistance coil needs be both shorter and thicker wire and vice versa. This results in a difference that the lower resistance coil is heavier total, because the surface area increases with diameter linearly and the needed length reduces proportionately, but the cross sectional area increases at the square of diameter. Thus it heats up slower, with the 2 main parameters equal (power and surface area). Also, going so low resistance my iStick had to cut the voltage way down to get the same power caused it to run hotter, as predicted. Less efficient. On the other hand, a thick wire is more rugged mechanically than a thin one (which is NOT more likely to burn through, when actually comparable and not damaged), and the thick wired coil can be denser, less spread out.
The 2 ways to increase surface area, and therefore suitability for more power, are increased length, resulting in higher resistance, or thicker wire, which reduces resistance. Lacking other assumptions, resistance tells nothing about how big the coil is.
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I did a similar experiment and got fundamentally the same result. I did it with the same wire gauge in the same atties at the same power, the lower ohm using half the wire length of the 2 times higher resistance coils.
They vaped surprisingly similar but what set them apart was the higher ohm coils had noticeable heat up time compared to the lower as you would expect from the higher heat capacity. I expected the lower ohm build would vape noticeably hotter due to the higher heat flux from the lower coil surface area but the difference was minimal to me. Vapor production and flavor were quite similar, which means a bit different.
I really should have pursued this more at the time but I didn't feel the need as I really liked the vape I was experiencing and still do. It's hard to find any real incentive to spend time and energy on better understanding something that is working just fine
Just to be clear, since I probably was not in my original description, I wanted to make the two coils as close as possible, in terms of wire length and diameter. That was not terribly close
But much closer than if I had used the same gauge wire for both coils. The 0.5 ohm coil was 24ga, about 72mm length with about a 57mm cross sectional area (length * 1/2 circumference). The 1.5 ohm coil was 28ga, about 89mm length and about 45mm cross sectional area.
In practice, I had trouble distinguishing any difference when vaping at
14 and 20W, including ramp up time. I'm not saying the ramp up time was the same, I am just saying that for me, any differences in ramp up time were not noticeable. That perception is subjective, and someone else might come to a different conclusion with the same configuration or some other that accomplished the same basic resistance values, or different power levels.
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To summarize what what has become a filthy cesspit of a thread:
OP was peeved because people were (in his opinion) confusing Ohms law and Watts law. This is completely irrelevant to 99.99% of people who vape, ALL they need to know is the rules they need to follow so they don't over tax the amp limit of their batteries. It's as simple as that. The rest is semantics and perhaps an opportunity to show off real or imagined electrical engineering skills. You may as well argue what colour atoms are.
There are still a lot of people on ECF who do not know how to check the amp draw for a regulated mod, I was one until fairly recently. THIS is what needs to be rectified, because venting batteries is an experience no-one needs to have. If it makes OP happier, don't mention the names of either of the two dead guys, just impart the correct knowledge and point them towards steam-engine to model it for themselves.
For clarity's (or pity's or Pete's) sake:
The battery (input) side.
As the battery voltage falls, the amp draw will rise. Make sure your battery's CDR matches the lower of these two values. That's it.
The atomizer (output) side.
The whole point of a regulated mod is, you guessed it, it regulates. It delivers the power/watts to the coil that you request. What happens electrically on this side is separate from input/battery side and is irrelevant for the previously mentioned 99.99% of vapers. Arguing about what defines a watt, or what James Watts birthday was is not helping anyone.
Yes the actual mix of volts and amps that are multiplied together varies with the resistance of the coil, but happens internally on the chip, neither battery NOR the user cares or needs to know.
You can use any resistance coil you want. All that matters here is balancing the mass/surface area with the amount of power you choose to apply to it to get the heat-flux and vapor production that you want.
Variable Voltage
Regulated mods that offer a variable voltage mode/option are just giving the user a different interface value to look at. What happens electrically on both the input and output side is absolutely identical. It's there because Joe Bloggs knows roughly how hot 4 volts is, Johns Smith knows roughly how hot 50 watts is.
Model it in Battery drain and see for yourself.
OP was peeved because people were (in his opinion) confusing Ohms law and Watts law. This is completely irrelevant to 99.99% of people who vape, ALL they need to know is the rules they need to follow so they don't over tax the amp limit of their batteries. It's as simple as that. The rest is semantics and perhaps an opportunity to show off real or imagined electrical engineering skills. You may as well argue what colour atoms are.
There are still a lot of people on ECF who do not know how to check the amp draw for a regulated mod, I was one until fairly recently. THIS is what needs to be rectified, because venting batteries is an experience no-one needs to have. If it makes OP happier, don't mention the names of either of the two dead guys, just impart the correct knowledge and point them towards steam-engine to model it for themselves.
For clarity's (or pity's or Pete's) sake:
The battery (input) side.
As the battery voltage falls, the amp draw will rise. Make sure your battery's CDR matches the lower of these two values. That's it.
The atomizer (output) side.
The whole point of a regulated mod is, you guessed it, it regulates. It delivers the power/watts to the coil that you request. What happens electrically on this side is separate from input/battery side and is irrelevant for the previously mentioned 99.99% of vapers. Arguing about what defines a watt, or what James Watts birthday was is not helping anyone.
Yes the actual mix of volts and amps that are multiplied together varies with the resistance of the coil, but happens internally on the chip, neither battery NOR the user cares or needs to know.
You can use any resistance coil you want. All that matters here is balancing the mass/surface area with the amount of power you choose to apply to it to get the heat-flux and vapor production that you want.
Variable Voltage
Regulated mods that offer a variable voltage mode/option are just giving the user a different interface value to look at. What happens electrically on both the input and output side is absolutely identical. It's there because Joe Bloggs knows roughly how hot 4 volts is, Johns Smith knows roughly how hot 50 watts is.
Model it in Battery drain and see for yourself.
All I can say is that if I were a complete newb reading this thread I would be completely confused right now.
Rather than helping people to stay safe, it may well just confuse the issue. The partially blind leading the blind.
Sometimes a little knowledge is worse than none at all, especially when mixed with a whole load of assumptions.
Most people just want to be reassured that what they are doing is as safe as they can be.
do links to @Mooch battery tests that give accurate test results and Battery drain not cover this?
We don't need to know what formula to use, just how to fill in the box's with the appropriate information.
Maybe, just maybe we could also agree on a reasonable amount of headroom to increase the safety margin?
Rather than helping people to stay safe, it may well just confuse the issue. The partially blind leading the blind.
Sometimes a little knowledge is worse than none at all, especially when mixed with a whole load of assumptions.
Most people just want to be reassured that what they are doing is as safe as they can be.
do links to @Mooch battery tests that give accurate test results and Battery drain not cover this?
We don't need to know what formula to use, just how to fill in the box's with the appropriate information.
Maybe, just maybe we could also agree on a reasonable amount of headroom to increase the safety margin?
@beckdg the rc world has that too there are guys that swear charging a lipo at more than 1C is instant death and destruction,when 5C charging has been here for years
I'm going to make this simple...there are 2 laws we are concerned with here in this thread... you need to know that WATTS=volts x Amps or watts div by volts = amps if you cant get your head around that then DARWIN's law will be comming to see you soon
I'm going to make this simple...there are 2 laws we are concerned with here in this thread... you need to know that WATTS=volts x Amps or watts div by volts = amps if you cant get your head around that then DARWIN's law will be comming to see you soon
Yes, I'm aware.@beckdg the rc world has that too there are guys that swear charging a lipo at more than 1C is instant death and destruction,when 5C charging has been here for years
I'm going to make this simple...there are 2 laws we are concerned with here in this thread... you need to know that WATTS=volts x Amps or watts div by volts = amps if you cant get your head around that then DARWIN's law will be comming to see you soon
I'm 2genewb on RC forums... HP DPS 600PB How To Mod for charging power supply. - Electric Motors, ESCs, batteries, etc. @ URC Forums
And I charge my lipos @ 30 amps.
I also venture into the wild a bit...
Tapatyped
This has been very interesting-- like the way people rubber neck at auto accidents-- but I find I can't leave the heat issue alone. All expended energy, whether used to perform work or wasted in losses of one or another form, eventually becomes heat. If you view the universe as a closed space with a positive radius-- the Einstinian universe; the one humans directly percieve-- then all energy expended is never lost to the system (First Law of Thermodynamics, Conservation of Energy) but merely changes forms, eventually resulting in heat; following which this heat redistributes itself into isothermic form (Second Law of Thermodynamics, Entropy Always Increases).
This does not mean this heat is useful for vaping purposes, because thermodynamic distribution processes are neither instantaneous nor even particularly efficient. Further, vaping is itself antientropic; an attempt to reverse entropy, to impose order on a naturally chaotic (in the math sense) system. In vaping, we concentrate energy, by forcing electrons into batteries, then releasing them in specified current paths to fire a heat producing coil; this is, at best, temporary, until the Second Law takes over. Further, vaping can only occur between the sublimation and combustion temperatures (in oxygen atmosphere) of the ejuice. Temperatures expressed outside this regime do not result in vapor.
Still, it is improper to discuss what portion of expended energy emerges as heat; all of it does, every time. The question is rather efficiency: how much (or what percentage) of expended energy can be immediately used to produce vapor? What we're really talking about is the work:loss ratio.
This does not mean this heat is useful for vaping purposes, because thermodynamic distribution processes are neither instantaneous nor even particularly efficient. Further, vaping is itself antientropic; an attempt to reverse entropy, to impose order on a naturally chaotic (in the math sense) system. In vaping, we concentrate energy, by forcing electrons into batteries, then releasing them in specified current paths to fire a heat producing coil; this is, at best, temporary, until the Second Law takes over. Further, vaping can only occur between the sublimation and combustion temperatures (in oxygen atmosphere) of the ejuice. Temperatures expressed outside this regime do not result in vapor.
Still, it is improper to discuss what portion of expended energy emerges as heat; all of it does, every time. The question is rather efficiency: how much (or what percentage) of expended energy can be immediately used to produce vapor? What we're really talking about is the work:loss ratio.
VNeil: yes that would be a fairer comparison. Was still a good example to explain a point. If the coils are truly comparable, the differences should be subtle.
This is the example of coils that are actually different. However, Surface Area -- or simply how "big" the coil is -- is only one factor determining maximum power. Each factor is a limit, increasing one doesn't help without the other. In fact, everything being sort of matched results in the best vape.
I like a fairly low airflow -- even if I opened the atty's controller up wide, I wouldn't want to pull that much air through. Therefore, my power use is reduced and the coil can easily be larger than ideal. If that's the case, setting the power higher results in hot vapor output and burning on longer drags due to heat buildup. Setting it low results in slow warmup, the vapor still can get too hot during long drags due to increased coupling of the coil to the air, and flavor is reduced. There is no clear "sweet spot" on the settings.
I did a similar experiment and got fundamentally the same result. I did it with the same wire gauge in the same atties at the same power, the lower ohm using half the wire length of the 2 times higher resistance coils.
They vaped surprisingly similar but what set them apart was the higher ohm coils had noticeable heat up time compared to the lower as you would expect from the higher heat capacity. I expected the lower ohm build would vape noticeably hotter due to the higher heat flux from the lower coil surface area but the difference was minimal to me. Vapor production and flavor were quite similar, which means a bit different.
I really should have pursued this more at the time but I didn't feel the need as I really liked the vape I was experiencing and still do. It's hard to find any real incentive to spend time and energy on better understanding something that is working just fine
This is the example of coils that are actually different. However, Surface Area -- or simply how "big" the coil is -- is only one factor determining maximum power. Each factor is a limit, increasing one doesn't help without the other. In fact, everything being sort of matched results in the best vape.
I like a fairly low airflow -- even if I opened the atty's controller up wide, I wouldn't want to pull that much air through. Therefore, my power use is reduced and the coil can easily be larger than ideal. If that's the case, setting the power higher results in hot vapor output and burning on longer drags due to heat buildup. Setting it low results in slow warmup, the vapor still can get too hot during long drags due to increased coupling of the coil to the air, and flavor is reduced. There is no clear "sweet spot" on the settings.
I must urge you to go back and re-read my initial post again.
Everything you have been lecturing me on since, is all encompassed by a single sentence:
I chose my words carefully. Including 'instantly' and 'emitted'. None of which is at odds with any of your ensuing lectures. That is the source of my puzzlement.
"You can use any resistance coil you want"
Not necessarily. All regulated mods have a minimum and maximum possible output voltage, and a maximum output current (regardless of voltage, separate from max power). So anyone pushing the envelope of high power/low coil resistance can run into that. People doing modest builds at modest power levels probably would not.
Wow this thread is amazing me, it really is not as complicated as people are making it, if you put a wattmeter across a coil and set it to 50 watts you will read 50 watts, the coil is a fixed pure ohmic resistance, there is no magnetism involved or any other type of opposition to current flow, current will travel through the coil creating power that will be dissipated as heat, no questioning it. Energy can not be created or destroyed, you're using the energy from your battery and converting it to heat, it's really not that hard to understand. Any other type of energy loss would be negligible.
I mainly took issue with this: "Just as resistance tells next to nothing about how a coil performs - wattage applied to the coil is equally nondescript."
But I'm going to do this thread a favor and not get into a pissing match about it. If you want to believe wattage is meaningless, go for it. After all, for a typical coil you are hanging on what happens in the first half second or so to back up that declaration.
I know, it was just another bit of information that didn't need to be included, for the sake of clarity.
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