Wrapping my head around Sub-ohm Vaping.

[JujiKabane]

Hi guys, I'm relatively new to vaping in general, and have been doing a lot of studying on this subject recently. That said, I'm not sure if I'm confusing myself or just failing to grasp certain aspects of this, but for safety I'd like to clear things up if possible.

For starters, I'm using a Kangertech Kbox mini 50W vw mod running a MXJO 18650 2500Mah 35a battery. After doing some research it seems the CDA is somewhere around 20A safely on this battery. I've also found the safe operating range is between 3.3v and 4.2v (Please correct any of this if I'm wrong).

I've just picked up a Kanger OCC 0.5 ohm coil, and I want to make sure that I'm using this thing safely before I put it in and blow up my house. After checking my battery on my multimeter it's currently reading 3.9v and to be safe, counting +/-.2 ohms on the coil at .3ohm the amps should total out to 13a. Fully charged at 4.2v = 14a.

Now this is where I get confused; does this mean running the mod at it's maximum output of 50w is reasonably safe on the battery (Albeit, I'd imagine terrible for the cotton and taste), and is there any danger in lowering the wattage below a certain point? Or put more simply, is there a low end output I should be avoiding as well as the high end? Are there any recommended wattage ranges to run this thing at to not burn my coil out too quickly?

If my understanding is correct, I'm in the clear, but I'd rather be safe than sorry, so please let me know if my math is off, or I need to be worried. Thanks!

 

[Adan]

It would not be dangerous to start at 7 watts.
I would start 15-20 on the .5 coils and adjust up as needed.
The device can be used at 50w, but I would not recommend using any device at its limits.
Use the same precautions as you would with any electronic device. If it begins to generate heat, discontinue use.
Same goes for the batteries, if they get hot while charging or using, or show signs of physical damage, discontinue use.
I would recommend an external battery charger as the small usb plug can wear out or become damaged.
Store and transport batteries the same way you would other batteries to prevent damage and electrical shorts.

 

[djsvapour]

I've also found the safe operating range is between 3.3v and 4.2v (Please correct any of this if I'm wrong).

You could be wrong, you could be right. I vote 'right' in general given your explanation. The Volts alone don't tell the whole story. I don't run anything on less than 5.0v usually, as I never drop under 1.2ohms on factory coils. If I was to use a 0.5ohm coil with a good quality battery (min 20a) then I might not top 4 volts.
If your coil is reading 0.3ohms use a calculator or trust your mod to keep on the safe path. You don't need to account for the exact voltage of the battery i.m.o. It make no difference, this is what the chip in the mods do (in a way).

If the mod doesn't give you the amps, some do, not all; then take the ohm reading and the watts, enter them into a calculator and see what comes back.

For example, if I put a 0.5ohm coil on my mod it might read 0.5 or 0.6 or even 0.62 depending on the decimal point of the mod. Let's say it reads 0.62 and I have set it to 24.8 watts. The calculator tells me I'm running it at just under 4.0v and just over 6.0 amps. ( 3.9v / 6.3a )

If I keep pushing the power, at some point the mod will 'tell me'. It will also stop working if the battery is too depleted.

The idea that you should account for an atomizer being 0.2 +/- is also not worth thinking about too long. The mod will tell you the resistance and adjust accordingly.

Is 50w usable? Sure it is. There are tanks/coils that can do 50w. A 0.3ohm coil will get up to 50w no trouble and the amps will be well short of danger zone of the amps IF you have a genuine battery with PROVEN specification.
I think most would agree, leave a good few amps in the locker for safety.

 

[Adan]

Ok, anyone?
Now, should I tell the OP how much flat out abuse I have put mine through?

 

[JujiKabane]

Thanks for the tips guys. Everything seems to be working fine, well within amp range. Unfortunately, I just learned the hard way 18mg liquid on a sub ohm coil is like injecting nicotine into your eyeballs. Gonna have to run out and buy some tamer juice. X)

 

[Adan]

Thanks for the tips guys. Everything seems to be working fine, well within amp range. Unfortunately, I just learned the hard way 18mg liquid on a sub ohm coil is like injecting nicotine into your eyeballs. Gonna have to run out and buy some tamer juice. X)

Maybe buy some 0mg of the same, and mix down?

 

[wheelie]

You are running a regulated mod. With the battery you have, you can run any factory coil you please and turn the power up or down where you please. Regulated mods have safety's in place that protect you. No need to worry about the mod unless perhaps you battery wrapper gets ripped or something like that. You are worrying to much about nothing. Get into mechanical mods with no protection and run strait off the battery according to the coil then that worry you have would come into effect. CHEERS!

 

[Frenchfry1942]

I don't use mine at their max wattages just for the safety. I just don't trust companies when they say things in advertising. I never max out batteries either.

 

[sofarsogood]

Worrying is good if it gets you learning the fundamentals and understanding the risks however minimal they might be. I want to brag about how I get a satisfying vape with less powwer instead the reverse. Higher ohm coils turn more of the power into heat than low ohm coils. With watts control and temp control I don't seem the point of running low ohm coils. But I only do single coils, don't care about clouds, and want good battery endurance.

 

[suprtrkr]

You have the general idea right. Using a regulated mod like your Kbox, the amp draw is calculated by set watts divided by the minimum battery voltage (the point at which the mod stops working because the battery is too low). In most mods that last is around 3.2 volts. Thus 50 / 3.2 = 15.63 amps. For safety sake and best accuracy, you also have to account for efficiency losses on the board. In most mods these run in the 5-10% range. Guessing 5%, then 15.63 x 1.05 = 16.41 amps. This should be safe on a 20 amp battery; you will be loading it to about 80% of its capacity. The amp draw will be lower if the battery is more charged than 3.2V or the watts set below 50.

And yes, by all means, get some tamer juice. Get some 0 nic in the same flavor and mix it down by volume if you like; a bottle of 18 plus a bottle of 0 equals two bottles of 9, and so forth. If you want to mix smaller quantities, get some cheap plastic syringes and mix by milliliter.

 

[edyle]

Hi guys, I'm relatively new to vaping in general, and have been doing a lot of studying on this subject recently. That said, I'm not sure if I'm confusing myself or just failing to grasp certain aspects of this, but for safety I'd like to clear things up if possible.

For starters, I'm using a Kangertech Kbox mini 50W vw mod running a MXJO 18650 2500Mah 35a battery. After doing some research it seems the CDA is somewhere around 20A safely on this battery. I've also found the safe operating range is between 3.3v and 4.2v (Please correct any of this if I'm wrong).

I've just picked up a Kanger OCC 0.5 ohm coil, and I want to make sure that I'm using this thing safely before I put it in and blow up my house. After checking my battery on my multimeter it's currently reading 3.9v and to be safe, counting +/-.2 ohms on the coil at .3ohm the amps should total out to 13a. Fully charged at 4.2v = 14a.

Now this is where I get confused; does this mean running the mod at it's maximum output of 50w is reasonably safe on the battery (Albeit, I'd imagine terrible for the cotton and taste), and is there any danger in lowering the wattage below a certain point? Or put more simply, is there a low end output I should be avoiding as well as the high end? Are there any recommended wattage ranges to run this thing at to not burn my coil out too quickly?

If my understanding is correct, I'm in the clear, but I'd rather be safe than sorry, so please let me know if my math is off, or I need to be worried. Thanks!

1: "safe operating range is between 3.3v and 4.2v"
Your fully charged lithium battery is 4.2 volts.
As the battery gets used the voltage drops.
When the voltage drops down to about 3.3, your kbox will stop using the battery; the battery is considered discharged.

2: at 50 watts, if the battery is down to 3.3 volts, the amp draw is 50/3.3 = 15 amps.

3: there is no danger is lowering the wattage.

 

[Ryedan]

For starters, I'm using a Kangertech Kbox mini 50W vw mod running a MXJO 18650 2500Mah 35a battery. After doing some research it seems the CDA is somewhere around 20A safely on this battery. I've also found the safe operating range is between 3.3v and 4.2v (Please correct any of this if I'm wrong).

Welcome to ECF JujiKabane

You've got some great answers already. The part about safe voltage operating range relates to battery voltage not mod output voltage. Your batteries will be very close to 4.2V when fully charged and that will drop slowly as they discharge. The mod will shut you down when they reach about 3.3V no-load. The voltage the mod applies to your atty is irrelevant to battery safety. That is all about the watts you set on a VW mod. This is not true with VV or mech mods.

With a single 20A battery you're not going over 20A at 50 watts so you have no restrictions. Vape it at any power setting you want

 

[bwh79]

I've also found the safe operating range is between 3.3v and 4.2v (Please correct any of this if I'm wrong).

Note that that's referring to the charge state of the battery itself, not the output setting of your device. There is no lower safety limit on the power output, just an upper one. You would be perfectly safe setting your device for 1 volt and firing it, if it went that low. It probably wouldn't work very well, but it'd be perfectly safe. When the battery itself dips down to 3.2v or under, though, then it's time for a recharge (you can actually probably get away with a bit lower than that, but it never hurts to recharge early, either, as these lithium-based batteries don't have the "memory" issues of your granddad's nickel-based rechargeables.)

 

[daviedog]

When your battery icon shows half, 3.6 volts or so change them. Not a safty issue but they will last longer.
Don't use those batts to sub ohm in a mech..