Ive heard about it and all but I still don’t get it. Can anyone just break it down for me? I got the demon killer 48 pc 8in1 to go with my pulse rda kit with a 18650 battery. Using dual coils will cut the ohms in half. Single coil is as stated on the container? What coil/coils can I use? Are all safe to run single/dual?
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Newbie here. Ohms law
- Thread starter Suz_Toy
- Start date
therinrik
Member For 1 Year
Ok, so Ohm's law is just one equation. V = I * R. MAKE SURE TO USE THE CONTINUOUS DISCHARGE VALUE FOR AMPERAGE //NOT// PULSE
Here, V is your voltage, which is usually printed on your battery. That number is your voltage at a full charge. It's usually 4.2 V, but you should look up Mooch's battery reviews to be safe. I is your current in amperes. The manufacturer of your battery also posts amp tolerances online, which is just a measure of how much electricity can safely flow through the cell at once (gross oversimplification). R is your resistance in ohms.
So, all you have to do to know if your battery is safe is to take your two known values (peak voltage of the battery and resistance of the coil) and plug them into the equation. Solving for I in this situation gives you the amount of electricity drawn by the circuit from one end of the battery to the other. If I is lower than your tolerance, you're safe.
Example: My batteries have a peak voltage of 4.2 volts and an amp tolerance of 20 amps under continuous discharge. Given this, and two coils of .66 ohms each (for a combined resistance of .36 ohms), we can substitute these values into the equation like this
4.2 = I * 0.36
Solving for I gives I = 4.2 / 0.36
which equals out to I = 11.6667 amps, which is well within the safe range of my battery. In fact, you might say it's a little lacking in power.
To get your wattage, W = A * V (amps times volts). Using my mod as an example again, I would have 4.2V * 11.66667A = 49W
Reply to this saying whether you got it or not. I'd hate for someone to blow themselves up for fear of annoying people. Please be safe.
Here, V is your voltage, which is usually printed on your battery. That number is your voltage at a full charge. It's usually 4.2 V, but you should look up Mooch's battery reviews to be safe. I is your current in amperes. The manufacturer of your battery also posts amp tolerances online, which is just a measure of how much electricity can safely flow through the cell at once (gross oversimplification). R is your resistance in ohms.
So, all you have to do to know if your battery is safe is to take your two known values (peak voltage of the battery and resistance of the coil) and plug them into the equation. Solving for I in this situation gives you the amount of electricity drawn by the circuit from one end of the battery to the other. If I is lower than your tolerance, you're safe.
Example: My batteries have a peak voltage of 4.2 volts and an amp tolerance of 20 amps under continuous discharge. Given this, and two coils of .66 ohms each (for a combined resistance of .36 ohms), we can substitute these values into the equation like this
4.2 = I * 0.36
Solving for I gives I = 4.2 / 0.36
which equals out to I = 11.6667 amps, which is well within the safe range of my battery. In fact, you might say it's a little lacking in power.
To get your wattage, W = A * V (amps times volts). Using my mod as an example again, I would have 4.2V * 11.66667A = 49W
Reply to this saying whether you got it or not. I'd hate for someone to blow themselves up for fear of annoying people. Please be safe.
therinrik
Member For 1 Year
That seems to be the case if this (https://www.elementvape.com/demon-killer-8-in-1-coil-prebuilt-set) is what you meant by the demon killer 8 in 1 set.
https://www.e-cigarette-forum.com/t...s-accurately-rated-15a-looks-like-30q.749545/
The second link is Mooch's review of what I think is your battery. He rates the cell at pretty much what is stated, but you should note that the cell actually operates somewhat below the average temperature for this class of battery at 20 amps, but that after 25 amps, the temperature of the cell rises dramatically under continuous discharge. This means it would be wise to stay within the 20 amp range. If you're unsure about any numbers, just run your known values (Voltage and Resistance) through the Ohm's law equation so that you know how much current you're drawing (Amps). A cursory look at the resistances on the box in the picture in the first link tells me that you're perfectly safe though.
You're probably fine, but it is good that you're not some dude that thinks, "I'm not stupid, so nothing's going to happen." The fact that you took the time to ask and wait for an answer shows that you have at least a but of caution, so load up those coils and see how they do!
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KingPin!
In my defence, I was left unsupervised ^^
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Hiya Suz the Efset is a re-wrap as such always be careful trusting what’s on the sticker (assume it’s purple?)
However the 20A continuous discharge is really where you want to be keeping it.
To remain completely on the safe side use a battery at it’s theoretical max voltage (4.2V)
you know the resistance of your coil. You should be using an ohm reader at the very least...don’t build straight onto a mech and don’t just use the coil box as a guide....this is really important for ensuring you don’t have a short as well.
You can calculate the amp draw on a mech using
I (current) = Voltage (4.2v) <divide by> Resistance (ohms)
The aim is to keep the build within the continuous discharge rating not the pulse rating
Think of current as the flow (I always use a hosepipe analogy to explain it)....if you are asking for more current than the battery can give it heats up trying...too much and you damage the cell and other bad things happen...
Once you are competent building you can start to push it a little....for instance take into consideration voltage sag and internal resistance which lowers the max voltage.... but that is for another time get the basics right first
However the 20A continuous discharge is really where you want to be keeping it.
To remain completely on the safe side use a battery at it’s theoretical max voltage (4.2V)
you know the resistance of your coil. You should be using an ohm reader at the very least...don’t build straight onto a mech and don’t just use the coil box as a guide....this is really important for ensuring you don’t have a short as well.
You can calculate the amp draw on a mech using
I (current) = Voltage (4.2v) <divide by> Resistance (ohms)
The aim is to keep the build within the continuous discharge rating not the pulse rating
Think of current as the flow (I always use a hosepipe analogy to explain it)....if you are asking for more current than the battery can give it heats up trying...too much and you damage the cell and other bad things happen...
Once you are competent building you can start to push it a little....for instance take into consideration voltage sag and internal resistance which lowers the max voltage.... but that is for another time get the basics right first
therinrik
Member For 1 Year
Big +1 for mentioning an ohm reader! I shouldn't have assumed that OP had one. ThanksHiya Suz the Efset is a re-wrap as such always be careful trusting what’s on the sticker (assume it’s purple?)
However the 20A continuous discharge is really where you want to be keeping it.
To remain completely on the safe side use a battery at it’s theoretical max voltage (4.2V)
you know the resistance of your coil. You should be using an ohm reader at the very least...don’t build straight onto a mech and don’t just use the coil box as a guide....this is really important for ensuring you don’t have a short as well.
You can calculate the amp draw on a mech using
I (current) = Voltage (4.2v) <divide by> Resistance (ohms)
The aim is to keep the build within the continuous discharge rating not the pulse rating
Think of current as the flow (I always use a hosepipe analogy to explain it)....if you are asking for more current than the battery can give it heats up trying...too much and you damage the cell and other bad things happen...
Once you are competent building you can start to push it a little....for instance take into consideration voltage sag and internal resistance which lowers the max voltage.... but that is for another time get the basics right first
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KingPin!
In my defence, I was left unsupervised ^^
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Also see this thread Suz
http://vapingunderground.com/threads/moochs-video-library-and-battery-table-links.384867/
It has all the links and vids you’ll wanna invest some time in going through
http://vapingunderground.com/threads/moochs-video-library-and-battery-table-links.384867/
It has all the links and vids you’ll wanna invest some time in going through