# I don't understand how 30Q's can do 100+ watts



## aktorsyl

As the subject says - I studied up but this part still confuses me.

Unless I'm mistaken, in the average regulated mod (taking my Predator228 as an example), the batteries are in series. This means double the voltage, but still the same current - and therefore, the same max discharge rate amperage as for a single cell. For a 30Q, that's still 20A total (well, 15A total according to them).

So, how can a mod with two 30Q's fitted do more than 100W? At 60W on 0.26ohm I'm already pulling 15A. According to my calculations, I'd be well past the battery safety limit if I go for 80W already.

But people are doing it and it works, hence my statement that I'm missing something obvious here  Care to help me out?

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## Christos

aktorsyl said:


> As the subject says - I studied up but this part still confuses me.
> 
> Unless I'm mistaken, in the average regulated mod (taking my Predator228 as an example), the batteries are in series. This means double the voltage, but still the same current - and therefore, the same max discharge rate amperage as for a single cell. For a 30Q, that's still 20A total (well, 15A total according to them).
> 
> So, how can a mod with two 30Q's fitted do more than 100W? At 60W on 0.26ohm I'm already pulling 15A. According to my calculations, I'd be well past the battery safety limit if I go for 80W already.
> 
> But people are doing it and it works, hence my statement that I'm missing something obvious here  Care to help me out?


At 100w the voltage would be 5.1v used by the regulated mod leaving the amps at about 20A.
http://www.steam-engine.org/ohm.asp


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## BubiSparks

Because at your given settings, the mod is only pushing around 4volts (V=P/I), whereas it has over 8 volts available assuming fully charged cells. The theoretical maximum (excluding losses due to the mod's efficiency) is around 160W (P=VxI)


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## Christos

Just to add at 150w the mod is pulling 25A. Thus is not safe as I suspect your question is all about.
There is a thread about this and how most people are under the illusion that a regulated mod will safety protect you but it's not true.


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## Christos

https://www.ecigssa.co.za/battery-safety-even-in-regulated-mods.t35829/


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## BubiSparks

@Christos Please fix your typo (1p0w)... I know the p and 0 keys are close to each other, but you're really gonna confuse the guy.....

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## Christos

BubiSparks said:


> @Christos Please fix your typo (1p0w)... I know the p and 0 keys are close to each other, but you're really gonna confuse the guy.....


Well spotted sir!


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## gertvanjoe

Something to add. Regulated mods pulse at a high frequency which allows it to limit the current as opposed to a mech which drains directly from the battery. So yes, higher current drains on regulateds are safer as the calculated level assumes mechanical connection, but only within parameters that are not easily available ( frequency ). So best treat your own calculations as purely mech and stay safe. 

Source : Electrician with switchmode device ( IGBT's and thyristors ) background.


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## gertvanjoe

Here's a nice write-up for the deeper workings : https://en.wikipedia.org/wiki/Boost_converter.

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## BioHAZarD

gertvanjoe said:


> Here's a nice write-up for the deeper workings : https://en.wikipedia.org/wiki/Boost_converter.


That math is too complicated so early in the morning

Reactions: Funny 2


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## gertvanjoe

BioHAZarD said:


> That math is too complicated so early in the morning



True, but just read the working principle for now then

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## Feliks Karp

gertvanjoe said:


> Here's a nice write-up for the deeper workings : https://en.wikipedia.org/wiki/Boost_converter.



Is there a need to boost in 2 + battery mods though, always thought it would buck the voltage, or do they use the same electronics?


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## zadiac

I think you guys scared the OP away...lol

Reactions: Agree 1


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## BioHAZarD

zadiac said:


> I think you guys scared the OP away...lol


Its that math  

Sent from my Note 4


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## gertvanjoe

Feliks Karp said:


> Is there a need to boost in 2 + battery mods though, always thought it would buck the voltage, or do they use the same electronics?



Same electronics switched differently.

Reactions: Like 1


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## BubiSparks

Agree @zadiac  That's why I didn't go there. Keep it simple and ignore the tricks of the trade regarding PWM especially for noobs.


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## gertvanjoe

You don't know that which you do not know. Inspiring people with a snippet of information can sometimes open up a whole new world to them. The vary same technique is used in MLM's  Only there they just don't tell you to first get you in the rabbit hole and as a paying customer with carrots you feel obliged to go deeper ( what makes you think I don't like em  )

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## aktorsyl

BubiSparks said:


> @Christos Please fix your typo (1p0w)... I know the p and 0 keys are close to each other, but you're really gonna confuse the guy.....


Haha thanks - but I figured it out


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## aktorsyl

Thanks for all the info so far! Let me explain why I'm asking:

I have two mods - a Predator228 and a Pico Dual. My main 2 atty's are the OBS Engine Nano (running at 35W @ 0.23 ohm) and the Sapor V2 (running at 60W @ 0.26 ohm dual-coil). On the Sapor, I'm pushing 15A currently with that 60W.

Yesterday I had to order more batteries and couldn't find my usual HG2's - only the 30Q's. Eventhough people say the 30Q's are fine at 20W, Samsung prefers to call them 15A batteries. If the output limit really was 15A, then I'd be living close to the edge if I use them with the Sapor V2, especially if I go to 70W which would exceed 15A.

An option is to only use HG2's on the RDA (65w), and the 30Q's on the RTA (35w). Just a bit of a schlep though.


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## Feliks Karp

aktorsyl said:


> Thanks for all the info so far! Let me explain why I'm asking:
> 
> I have two mods - a Predator228 and a Pico Dual. My main 2 atty's are the OBS Engine Nano (running at 35W @ 0.23 ohm) and the Sapor V2 (running at 60W @ 0.26 ohm dual-coil). On the Sapor, I'm pushing 15A currently with that 60W.
> 
> Yesterday I had to order more batteries and couldn't find my usual HG2's - only the 30Q's. Eventhough people say the 30Q's are fine at 20W, Samsung prefers to call them 15A batteries. If the output limit really was 15A, then I'd be living close to the edge if I use them with the Sapor V2, especially if I go to 70W which would exceed 15A.
> 
> An option is to only use HG2's on the RDA (65w), and the 30Q's on the RTA (35w). Just a bit of a schlep though.



You are only pulling 9.4 A with 60 w.

TLDR; On a regulated mod amp draw = ((wattage/number of batteries)/minimum volt capacity) - (so 60/2)/3.2) = 9.4A

* the coil forms its own circuit with the chip, and the chip delivers volts based on the coil resistance and selected wattage. Those are the volts on screen, if you screen is displaying amps, it is also out put amps, the amps coming off of the chip, not the amp draw off the battery.

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## aktorsyl

Feliks Karp said:


> You are only pulling 9.4 A with 60 w.
> 
> TLDR; On a regulated mod amp draw = ((wattage/number of batteries)/minimum volt capacity) - (so 60/2)/3.2) = 9.4A
> 
> * the coil forms its own circuit with the chip, and the chip delivers volts based on the coil resistance and selected wattage. Those are the volts on screen, if you screen is displaying amps, it is also out put amps, the amps coming off of the chip, not the amp draw off the battery.


Ohh. So long question short: if I pull 80W off a Samsung 30Q battery (15A max, some say 20A max), it should actually result in:

Coil: single
Batteries: 2 (series)
Watts: 80W
Ohms: 0.26
Volts: 4.5V
Amp requirement: 17.5A
Amps from chip: wattage / batteries / volts = 80 / 2 / 4.5 = 8.8A
True amps from battery: 8.8A
Headroom: 15A - 8.8A = 6.2A


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## Feliks Karp

aktorsyl said:


> Ohh. So long question short: if I pull 80W off a Samsung 30Q battery (15A max, some say 20A max), it should actually result in:
> 
> Coil: single
> Batteries: 2 (series)
> Watts: 80W
> Ohms: 0.26
> Volts: 4.5V
> Amp requirement: 17.5A
> Amps from chip: wattage / batteries / volts = 80 / 2 / 4.5 = 8.8A
> True amps from battery: 8.8A
> Headroom: 15A - 8.8A = 6.2A


-

If the batteries are fully charged yes you will use 4.5 V BUT you use the lowest to factor in safety so that you know that you are safe all the way down the battery's charge.

So 40 watts / 3.2 v = 12 amp draw off battery but yes if your batteries were charged and have 4.5 V you would be pulling 8.8 A.

Reactions: Can relate 1


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## aktorsyl

Feliks Karp said:


> -
> 
> If the batteries are fully charged yes you will use 4.5 V BUT you use the lowest to factor in safety so that you know that you are safe all the way down the battery's charge.
> 
> So 40 watts / 3.2 v = 12 amp draw off battery but yes if your batteries were charged and have 4.5 V you would be pulling 8.8 A.


Oh right, so you always work on 3.2V as that's the point where the mod cuts out due to low batt.


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## Feliks Karp

aktorsyl said:


> Oh right, so you always work on 3.2V as that's the point where the mod cuts out due to low batt.



Mods generally do cut out at increments of 3.2 v but you use the lowest when calculating amp draw in a regulated mod because that's when the load on the battery will be the highest. 

Say you want 120 W , even at 4 V the amp draw is still safe at 14 A but as you get to 3.2 V it will go up to 18.8 A , so you are starting to redline the battery, now most of mods don't show the battery charge passed a graphical representation, so as it gets lower you are starting to get to the "danger zone" and you may not realise it, so you use the lowest charge to protect yourself.

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## aktorsyl

Feliks Karp said:


> Mods generally do cut out at increments of 3.2 v but you use the lowest when calculating amp draw in a regulated mod because that's when the load on the battery will be the highest.
> 
> Say you want 120 W , even at 4 V the amp draw is still safe at 14 A but as you get to 3.2 V it will go up to 18.8 A , so you are starting to redline the battery, now most of mods don't show the battery charge passed a graphical representation, so as it gets lower you are starting to get to the "danger zone" and you may not realise it, so you use the lowest charge to protect yourself.


Right, got it. So using this formula, I determined that the mod's amp display reaches 19A at the same time the formula reaches 14A. Wish one could change it so that the mod shows true amps from the batteries.


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## stevie g

The MOD will keep you safe. 

It monitors volts and amps and when you're over working your batteries the MOD will sense an error state and show you a LOW BATTERY or CHECK BATTERY warning.

Basically if your battery is not up to the task you'll get an error message versus a MECH MOD that has no monitoring of the battery and will allow all sorts of stupid mistakes which I'm guilty of several times over.

To the guy who said we think we're safe on REGULATED MODS but we aren't... No we really are safe especially compared to MECH users. 

I enjoy my mech but it does require a lot more attention than digital devices.

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## Feliks Karp

Sprint said:


> The MOD will keep you safe.
> 
> It monitors volts and amps and when you're over working your batteries the MOD will sense an error state and show you a LOW BATTERY or CHECK BATTERY warning.
> 
> Basically if your battery is not up to the task you'll get an error message versus a MECH MOD that has no monitoring of the battery and will allow all sorts of stupid mistakes which I'm guilty of several times over.
> 
> To the guy who said we think we're safe on REGULATED MODS but we aren't... No we really are safe especially compared to MECH users.
> 
> I enjoy my mech but it does require a lot more attention than digital devices.




I think @Christos just meant that it's good to exercise caution and safety understanding, I mean like a microwave is pretty safe but I bet I make one do some exciting stuff.

Reactions: Agree 1 | Funny 2


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## aktorsyl

Sprint said:


> The MOD will keep you safe.
> 
> It monitors volts and amps and when you're over working your batteries the MOD will sense an error state and show you a LOW BATTERY or CHECK BATTERY warning.
> 
> Basically if your battery is not up to the task you'll get an error message versus a MECH MOD that has no monitoring of the battery and will allow all sorts of stupid mistakes which I'm guilty of several times over.
> 
> To the guy who said we think we're safe on REGULATED MODS but we aren't... No we really are safe especially compared to MECH users.
> 
> I enjoy my mech but it does require a lot more attention than digital devices.


I was hoping you'd say that  How does the mod know what the maximum discharge rate (in amps) are for the batteries, though?

I know the mod regulates most of the safety features and electricity for you, but I like to understand exactly how. I don't mind things being automatic, as long as I know what's happening behind the scenes. And in that I agree with @Christos - I like to exercise sound/good practice, even if it's not nececssary.


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## Christos

@Sprint what Uncle @Feliks Karp said.

Excercising cauting is always a good idea.


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## stevie g

aktorsyl said:


> I was hoping you'd say that  How does the mod know what the maximum discharge rate (in amps) are for the batteries, though?
> 
> I know the mod regulates most of the safety features and electricity for you, but I like to understand exactly how. I don't mind things being automatic, as long as I know what's happening behind the scenes. And in that I agree with @Christos - I like to exercise sound/good practice, even if it's not nececssary.



Best practices are great and I'm glad they are applied across the forum.

Your MOD will monitor battery sag and trip to an error code if voltage drops below the programmed threshold. 

In my rudimentary understanding anyway!!!


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## clinton.spaceship

The beauty of the computer chip, with all its safety features!
Also get the Vape tool - from playstore will help calculate ohms law, build coils and mix some juice!






Sent from my GT-I9195I using Tapatalk

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