Don't forget about Watts Law
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Just so. Resistance is fixed (ignoring thermal flux and TCR in the conductors) in the circuits on both sides of the board, but they are usually not equal. Nor do they have to be.
Threads like this makes me wonder why manufacturers can't simply put a decent guesstimate of amp draw on the display of your average VV/VW/TC mod. Would make things one hell of a lot easier for the end user.
They come here and ask what batts to buy.
Which, I, personally consider just as well if they're going to stick to regulated devices.
I wouldn't expect you to become a mechanic to drive your vehicle. And let's be honest, an overworked, massive, exploding battery in your face could very easily be the least of your worries.
Tapatyped
The battery doesn't see 2 fixed resistances and a variable voltage regulator. The battery sees a circuit with 1 resistance that changes according to user setting and battery output voltage.
That's what I was referring to.
Tapatyped
Yup. And I was trying to say the resistance in the upstream or battery circuit is not directly connected to the downstream or coil circuit, and therefore neither is relevant to the other.
Sadly, this is probably the tenth(at least) thread with these same discussions that I have read, that pretty much leaves every non electrical engineer going 
There are literally millions of things people can devote their lives to that do not require a Degree in electronics.......................and they never get it.
Yet, as the thread progresses, it becomes more and more a - let my prove my knowledge -argument, and so confusing to some that they bail out, Understanding Less than when they started reading.
My question for the Experts - not clearly addressed in the opening post.
Rather than Watts Law vs. Ohms Law
Why precisely is Watts Law so important to the Average Vaper?
okay, Fight!
There are literally millions of things people can devote their lives to that do not require a Degree in electronics.......................and they never get it.
Yet, as the thread progresses, it becomes more and more a - let my prove my knowledge -argument, and so confusing to some that they bail out, Understanding Less than when they started reading.
My question for the Experts - not clearly addressed in the opening post.
Rather than Watts Law vs. Ohms Law
Why precisely is Watts Law so important to the Average Vaper?
okay, Fight!
Im not good at the qoutes thing yet,I will figure it out but I am at work right now(auto repair shop....lol and Im also a luthier)
but "batteries cant say no"
actually they can,its called venting and pretty much what all this is trying to avoid
"who cares about all the mathmatics and formulas?"
the guy that puts an 18650 designed for flashlights rated at 4 amps into a 75 watt evic mini...see above statement about venting
as Ive said before its not the quadratic equation or quantum physics its a 5th grade division problem...... watts divided by volts equals amps..........and it goes a long way to keeping you from burning yourself
but "batteries cant say no"
actually they can,its called venting and pretty much what all this is trying to avoid
"who cares about all the mathmatics and formulas?"
the guy that puts an 18650 designed for flashlights rated at 4 amps into a 75 watt evic mini...see above statement about venting
as Ive said before its not the quadratic equation or quantum physics its a 5th grade division problem...... watts divided by volts equals amps..........and it goes a long way to keeping you from burning yourself
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Exactly, that's why you need to use watts law to determine your amps. Your batteries are supplying a set wattage, and the current is what flows through them to supply that wattage, the board itself does the adjustments to ensure you get that power to your coil, you only need to worry that your batteries can safely deliver your set wattage to the board, and in order to know that you use watts law to determine the current draw, because as you said, batteries are rated in amps
Getting old. Gotten forgetful.
No shame in using aids:
Voltage to Wattage Chart
At one point in my life, Math was my love. I even maintained an inventory(very well) of over 15K parts and kept up with things in my head. Just one small part of my business. Those days are long gone due to life Stresses and health Issues.
Still, I manage to keep safe.
No shame in using aids:
Voltage to Wattage Chart
At one point in my life, Math was my love. I even maintained an inventory(very well) of over 15K parts and kept up with things in my head. Just one small part of my business. Those days are long gone due to life Stresses and health Issues.
Still, I manage to keep safe.
I did think about putting that in my original reply, but really, the battery is still trying to do what is being asked...but "batteries cant say no"
Actually they can, its called venting and pretty much what all this is trying to avoid
It just dies in the process. Spectacularly and dramatically.
Because if you don't at least do the checks, the following formula may come into effect:
overstressed battery x pain and burns = big medical bills + scars
That was my point about muddying the waters. It's a good thing there is steam-engine because that makes it easy and requires no maths, which is nice. Having said that, watts divided by volts isn't exactly rocket science is it?Sadly, this is probably the tenth(at least) thread with these same discussions that I have read, that pretty much leaves every non electrical engineer going
Oh, and to remember
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Just want to see if I understand.
On a variable wattage mod, to calculate the amp load from the battery(at a basic level):
Watts / battery voltage / number of batteries (not accounting for board inefficiency)
So if you have a 50 watt mod that uses a single 18650
at full charge it's 50/4.2/1 = 11.9 amp
at low voltage(more important) it's 50/3.2/1 = 15.6 amp
Is that right?
On a variable wattage mod, to calculate the amp load from the battery(at a basic level):
Watts / battery voltage / number of batteries (not accounting for board inefficiency)
So if you have a 50 watt mod that uses a single 18650
at full charge it's 50/4.2/1 = 11.9 amp
at low voltage(more important) it's 50/3.2/1 = 15.6 amp
Is that right?
Using a regulated power device as battery voltage decreases, amp drain/demand from the battery increases.
50w / 4.2v = 11.90a (1 battery)
50w / 3.2v = 15.62a ( 1 battery )
Neither take device inefficiency into account.
Some folks sure try hard to make schtuf seem more complicated than it is.
50w / 4.2v = 11.90a (1 battery)
50w / 3.2v = 15.62a ( 1 battery )
Neither take device inefficiency into account.
Some folks sure try hard to make schtuf seem more complicated than it is.
Totally agree. I am almost entirely unable to do math, beyond simple arithmetic, so I depend on the Steam Engine calculator to figure all this stuff for me. But one thing I do know very well: the higher resistance the coil is, the longer the battery will last. So yeah, it's very important to know the coil's resistance -- without that piece of info, you can't even use the Steam Engine calculator to know what the amp draw will be. The higher the resistance, the lower the amp draw = longer battery life.
Andria
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