E-Cigarette Forum Discussion Thread

[renstyle]

'Eh, I don't CALL him a sissy about not wanting to climb a ladder, I just think it. I only CALL him a sissy when he's running away and flailing wildly at a bumblebee.

EDIT: but I promise to never think mean things about ladders ever again thanks to this thread

(and no, he's not allergic to bees, just deathly terrified)

I've been told by the better half that I cannot be on a ladder either. I'd prolly end up killing myself, so it's good she's around.

 

[phonedude]

Okay, that's it. You've pushed me right over the edge. I absolutely do NOT want to think about bugs living in my eyelashes! 8-o

ETA: WHY did I click on that link...

Oh great. Now when I wake up and my eyes are all matted and sticky I will think of those little eyelash bugs.

Well, at least I won't attribute it to vaping. Now I know.

 

[renstyle]

Yeah, it's big. I prefer the Sapphire for normal use but the Vision is nice for road trips. My old one had an early death, others have reported getting a month or more of use out of them.

The VV Ego is very nice, I have the VV passthru and I like it alot. They'll have more stock in a week or so.

Are you able to run that PT off "mere mortal" sub 2A USB ports at all? Since it never gets past 4.2, wasn't sure if it needed more current to operate, or was similar to the regular eGo PT (can work with a 1A USB supply with no issues).

 

[Randyrtx]

I honestly don't know Renstyle, I never use PC USB ports to power my passthrus unless they contain an in-line battery. This one doesn't have a battery. I don't know much about Ego passthrus other than that some are just a regular battery with a USB port on the end; those use about 450mA so would work on (almost) any USB port.

I've used it sucessfully on a 2A AC to USB wart, 2A 12VDC Car Adapter, 1.5A 5VDC Kensington Battery, and USB ports built into my Dell monitors. It should also work fine on a self-powered USB Hub with a 1.5A or better supply.

 

[LibertariaNate]

I honestly don't know Renstyle, I never use PC USB ports to power my passthrus unless they contain an in-line battery. This one doesn't have a battery. I don't know much about Ego passthrus other than that some are just a regular battery with a USB port on the end; those use about 450mA so would work on (almost) any USB port.

I've used it sucessfully on a 2A AC to USB wart, 2A 12VDC Car Adapter, 1.5A 5VDC Kensington Battery, and USB ports built into my Dell monitors. It should also work fine on a self-powered USB Hub with a 1.5A or better supply.

Personally I wouldn't use a PT on anything less than 3 amps, but that's just me being (perhaps) overly cautious. Let's say you're running the PT at 4.2V with a 2ohm atomizer/cartomizer...

Ohm's law calculations

volts / resistance = amps
4.2 / 2 = 2.1

Now I'm sure a 2 amp power supply can handle that extra tenth of an amp, but we all know that atomizers tend to degrade. Nevermind your wall wart might be of "questionable" quality. IME, the resistance of an atty tends to become lower over time. I have a few attys that started at 2.5ohms, but over their lifetime have dropped below 1.5 ohms.

4.2 / 1.5 = 2.8

Even if you drop the voltage to 3.3 you're still pulling over 2 amps.

3.3 / 1.5 = 2.2

Obviously if you're using cartos/attys with a higher resistance than 2 ohms this is probably a non-issue, but for people like me that regularly vape at 8-10 watts it's something we need to pay attention to.

I'm rambling... I'll show myself to the door.

 

[Randyrtx]

Personally I wouldn't use a PT on anything less than 3 amps, but that's just me being (perhaps) overly cautious. Let's say you're running the PT at 4.2V with a 2ohm atomizer/cartomizer...

Ohm's law calculations

volts / resistance = amps
4.2 / 2 = 2.1

Now I'm sure a 2 amp power supply can handle that extra tenth of an amp, but we all know that atomizers tend to degrade. Nevermind your wall wart might be of "questionable" quality. IME, the resistance of an atty tends to become lower over time. I have a few attys that started at 2.5ohms, but over their lifetime have dropped below 1.5 ohms.

4.2 / 1.5 = 2.8

Even if you drop the voltage to 3.3 you're still pulling over 2 amps.

3.3 / 1.5 = 2.2

Obviously if you're using cartos/attys with a higher resistance than 2 ohms this is probably a non-issue, but for people like me that regularly vape at 8-10 watts it's something we need to pay attention to.

I'm rambling... I'll show myself to the door.

You just had to make me get out my calculator, didn't you

The low resistance stuff was really intended for mods, not the "off-the-shelf" type batteries and passthrus. The stuff I use is all 2.5Ω or higher, but for the sake of nitpicking:

The VV Ego "Piper" PT uses PWM (pulse width modulation) to generate it's output, so you have to base the input current draw on 5V, not the output voltage, or better yet, the wattage.

4.2V / 2Ω = 2.1A ~ 8.82W -> @5V, I = P/E = 8.82W/5V = 1.76A

4.2V / 1.5Ω = 2.8A ~ 11.76W -> @5V, 11.76W/5V = 2.35A

3.3V / 1.5Ω = 2.2A ~ 7.26W -> @5V, 7.26W/5V = 1.45A

Note that these figures don't account for the efficiency of the converter, which is probably 90% or better, and can be as high as 98% with modern hardware. (I'm lazy or I'd do a spreadsheet that accounts for it)

Given worst case at 4.2V with a 2A USB supply (10W ~ 9.5W assuming 95% efficiency), the lowest resistance you could safely use would be (in theory):

R = E^2/P = 4.2V^2/9.5W = 1.86Ω

 

[LibertariaNate]

The VV Ego "Piper" PT uses PWM (pulse width modulation) to generate it's output, so you have to base the input current draw on 5V, not the output voltage, or better yet, the wattage.

Interesting for sure. I wasn't aware the PT you speak of uses PWM. For that matter, I didn't realize anything on the market used PWM. I've only heard/seen it being used in mods people build for themselves.

I'm not terribly familiar with the "technology", but the numbers look off. So you're saying that on a mod using PWM with a power source of 5v set to output 4.2v the resistance of the atty isn't really 2Ω, but closer to 2.8Ω? Or for calculating it just appears that way? It's a serious question.

I'm confused and my brain hurts...

 

[LibertariaNate]

To be honest, I was already deeply confused. My head has been pounding for the past couple of days too.

That's not your post's fault.

 

[Randyrtx]

Actually, your Darwin (and the Provari) uses PWM (also called DC-DC converter) technology if I'm not mistaken.

In conventional linear regulation, a variable control element acts as a resistance that drops a portion of the input voltage to generate a lower output voltage.

With PWM, a low resistance switch is used to "pulse" the input source between 0 volts and the full value of the input voltage at a high frequency. The equivalent output voltage is determined by averaging the "high" time of the pulse. By varying the pulse width, any voltage up to the power input level can be generated. In actual DC-DC power supplies, a capacitor is used on the output to "smooth" the pulse train to a steady DC value. Since we're really concerned only with generating a specific power level, the capacitor isn't needed.

Note that this descibes a "buck" converter circuit, where the output voltage is less than the input. For "boost" applications, where the output voltage is higher than the input, a storage element such as an inductor is used to "boost" the output of the converter pulse to a higher voltage. Combination buck/boost converters can generate an output voltage that is higher, lower, or equal to the input voltage.

Does this make more sense?

 

[LibertariaNate]

Yes. Thank you.

 

[DC2]

Does this make more sense?

I'd have to run it through some translation software before I could answer that question.
But I don't know what language it was written in?

 

[Randyrtx]

Thanks for asking... my brain enjoyed the engineering stimulation!

I've been giving thought to designing something, either as a box mod or a control box with an attached "passthru". At a minimum it would have a small display, USB for charging/programming, etc.

 

[Randyrtx]

I'd have to run it through some translation software before I could answer that question.
But I don't know what language it was written in?

Hardware geek-speak, of course!

 

[DC2]

Hardware geek-speak, of course!

Yeah, I'm not finding any translation websites for that.

 

[LibertariaNate]

Thanks for asking... my brain enjoyed the engineering stimulation!

I've been giving thought to designing something, either as a box mod or a control box with an attached "passthru". At a minimum it would have a small display, USB for charging/programming, etc.

I made a little control box for a PT. Works well, but a bit of a pain to adjust voltage. Not a big enough PITA to make me want to work on it some more though. It just stays on my desk and I have a little screw driver nearby should the need arise.

 

[renstyle]

You just had to make me get out my calculator, didn't you

The low resistance stuff was really intended for mods, not the "off-the-shelf" type batteries and passthrus. The stuff I use is all 2.5Ω or higher, but for the sake of nitpicking:

The VV Ego "Piper" PT uses PWM (pulse width modulation) to generate it's output, so you have to base the input current draw on 5V, not the output voltage, or better yet, the wattage.

4.2V / 2Ω = 2.1A ~ 8.82W -> @5V, I = P/E = 8.82W/5V = 1.76A

4.2V / 1.5Ω = 2.8A ~ 11.76W -> @5V, 11.76W/5V = 2.35A

3.3V / 1.5Ω = 2.2A ~ 7.26W -> @5V, 7.26W/5V = 1.45A

Note that these figures don't account for the efficiency of the converter, which is probably 90% or better, and can be as high as 98% with modern hardware. (I'm lazy or I'd do a spreadsheet that accounts for it)

Given worst case at 4.2V with a 2A USB supply (10W ~ 9.5W assuming 95% efficiency), the lowest resistance you could safely use would be (in theory):

R = E^2/P = 4.2V^2/9.5W = 1.86Ω

I was thinking only for "regular" resistance loads as well, your 2.5+ basically. Then I thought of dual-coil cartos (which I've been dying to try) and I did a mental facepalm.

I do appreciate the run-thru. I was aware of the PWM usage, but never considered looking at the equation from the "back-end", which really is more appropriate since we're talking about current draw.

Looks like my 1A cheapie car-2-usb adapter won't cut it for this device...

I'll look on the bright side: finally have a GOOD REASON to upgrade!

 

[DC2]

A sphincter says what?

 

[Randyrtx]

Huh?

On a side note... I just did a grocery run, and had heard that H.E.B stores were carrying e-cigs (if I had been born with a name like Howard E. ...., I would have changed it).

Sure enough, my local store has Blu kits and carts, and something called Nicotek. Even have accessories like chargers. Not real cheap, but not quite ripoff pricing either (unlike the local Smoking Everywhere kiosk at the mall).

 

[LibertariaNate]

On a side note... I just did a grocery run, and had heard that H.E.B stores were carrying e-cigs (if I had been born with a name like Howard E. ...., I would have changed it).

It was wise to shorten the store name to just his initials... Wiser still to distance the name further by using the slogan "Here Everything's Better".

 

[MadmanMacguyver]

(insert image of long trail of footprints in the desert and a man stumbling from heat exhaustion) Too hot, need water, must..... find........ unnngh!!!flop thump...


110 degrees here today maybe more too hot to look it might make it feel worse...When will it rain one of my shoes actually melted on asphalt today...