What are the advantages of VW Box Mods?

[edyle]

The way I understand it is ... Lets say you set your box mod voltage to output 3.8 volts.

When the fully charged battery in the box mod is above 3.8 volts, it will obviously lower the output voltage to the required 3.8 volts you set in it.

When the actual voltage in the box mod's battery slowly wears down below 3.8 volts, the electronics in the box mod has the ability to 'up' the output voltage to your required 3.8 volts.

And it will continue to produce the 3.8 volts while the battery wears down even lower .... up to a pre-set point where the box mod will just shut-down.

How can the box mod output the 3.8 volts when it's internal battery has actually gone below 3.8 volts? ..... I think it has to do with built-in capacitors.


One of the electronics gurus here maybe can explain it in more detail, but I think you get the point


EDIT .... I believe the circuit in the box mod that allows it to produce higher output voltages than what the battery is charged to is called a "Buck-Boost" converter.

The way it's done on many mods it it bumps up the output voltage to 6 volts (in the case of my vamo for example), but oscillates between 6 and 0.
For higher voltage it stays at 6 longer than for lower voltage.
If the required voltage is 6 volts, then it stays at 6 without oscillating.

 

[noel18]

Good discussion guys. Thanks for everyone chiming in. Still one thing I'd like to be clear on. Edyle said 'For example if you use a mech with 2 one ohm coils in dual coil configuration which works out to 0.5 ohm dual coil, you would use the same wire and build a 2 ohm single coil instead and vape that on your VW mod.'
And this is because I can manually crank up the watts?

 

[folkphys]

Good discussion guys. Thanks for everyone chiming in. Still one thing I'd like to be clear on. Edyle said 'For example if you use a mech with 2 one ohm coils in dual coil configuration which works out to 0.5 ohm dual coil, you would use the same wire and build a 2 ohm single coil instead and vape that on your VW mod.'
And this is because I can manually crank up the watts?

Well, it actually because you can crank up the volts on the 2ohm single coil in order to vape at near the same wattage as you would with mech and a 0.5ohm dual coil.

 

[edyle]

Good discussion guys. Thanks for everyone chiming in. Still one thing I'd like to be clear on. Edyle said 'For example if you use a mech with 2 one ohm coils in dual coil configuration which works out to 0.5 ohm dual coil, you would use the same wire and build a 2 ohm single coil instead and vape that on your VW mod.'
And this is because I can manually crank up the watts?

Yes that's one way of looking at it; instead of manually adding multiple coils, you make one big coil and manually crank up the watts.

It's because on a mech you are limited to the battery having a nominal voltage of 3.7 volts.

On the regulated mod you can run at higher voltages.
So with the 2 one ohm coils example at 3.7 volts you can instead take the same wire and make one big 4 ohm coil and turn up the voltage to 7.4 volts.

 

[KenD]

Wait what?

But assuming as battery voltage drops, the wattage also drops (even though on a regulated mod it should be more consistent), wouldn't this account for potentially over-drawing on amps? AKA: Should I worry about accidentally using too many amps if I go too long without charging my batteries?

A regulated mod will output the volts/watts you've set it to even when the battery charge drops. There's a risk that you'll draw more current than the battery is able to provide. Check the battery drain calculator on http://www.steam-engine.org, input your coil resistance (preferably the lowest resistance your device can use), the max voltage or wattage that your device can output, the battery voltage at which your device will shut down (usually 3.2-3.3v), the efficiency of the circuitry in your device (no device is 100% efficient), and you'll see what the maximum amp draw of your device might be. For example, a 50w device that can take a 0.3 ohm coil (like the zna50 I ordered last week ), in a worst case scenario of 80% circuitry efficiency, and device turning of when the battery's at 3.2 v, you'll need at least 20 amp batteries to be safe. A 100w device, with othetwise the same variables, would need a 40 amp battery (which don't exist) to be safe. I'm not sure if the amp draw is divided equally between 2 batteries wired in parallel or not. If it is, then that's the only safe way to use a 100w regulated device.

 

[folkphys]

1 other thing to note:

nyiddle's box uses a chip that (if my memory serves) regulates voltage in a downward fashion only("buck"). That is why his box might seem to him to "feel" a bit like a really awesome and powerful mech mod. If it uses two or more batteries, then they are connected in series, such that the total available voltage to the chip would be the sum of their individual remaining capacities. And then the chip takes that 6, 8, 10, 20 volts or whatever of all the batteries combined and chops it down to the level of his selected voltage. And if that selected voltage is actually just a relative setting, ie, some % of the total voltage at that very moment, then when his batteries begin to flag, so would the box's output voltage to the atomizer.

And in my experience, a really good clean mech can provide smoother and more powerful toots, because it has a near-zero voltage drop and far less fiddly bits sucking amperage on the way from battery to atomizer.

 

[suspectK]

The way it's done on many mods it it bumps up the output voltage to 6 volts (in the case of my vamo for example), but oscillates between 6 and 0.
For higher voltage it stays at 6 longer than for lower voltage.
If the required voltage is 6 volts, then it stays at 6 without oscillating.

Have you measured that?

Lowest it drops is 4.24 Volts... unfortunately that was about a year ago, and I didn't put a plot point for the peak Voltage...I do believe it was at 5 Volts though. Vape-pro/zmax chip in RMS/33.3Hz pulse.

 

[MrPlink]

Well, it actually because you can crank up the volts on the 2ohm single coil in order to vape at near the same wattage as you would with mech and a 0.5ohm dual coil.

While as far as sheer numbers are concerned this is true, but this should NOT be construed to mean that a (for example) that all coils will create comparable vape provided they are of the same wattage.

Try building a 1ohm single coil with 32g wire and set it 50w.
Now compare that to dual coil 26g .4ohm at 50w and tell me if you notice a difference.

 

[edyle]

Have you measured that?

Lowest it drops is 4.24 Volts... unfortunately that was about a year ago, and I didn't put a plot point for the peak Voltage...I do believe it was at 5 Volts though. Vape-pro/zmax chip in RMS/33.3Hz pulse.

No I didn't measure it myself with an oscilloscope but it's what I gathered from pbusardo's reviews on the vamo specifically.

 

[suspectK]

Ok... I've never had a Vamo in front of a scope, so I can't (dis/)prove

That could explain why I(and many others) never experienced the "rattlesnake"effect..hmmm

 

[edyle]

Ok... I've never had a Vamo in front of a scope, so I can't (dis/)prove

That could explain why I(and many others) never experienced the "rattlesnake"effect..hmmm

Maybe you misread the post?
Whether the voltage jumps between 4.24 and 6 or 0 and 6, you'd get the rattlesnake effect.

 

[suspectK]

Ummm...ok?

Edit-seriously? You missed my point.

I never PERCEIVED the "rattlesnake effect". I measured a pulse wave that was ~5 to 4.25 Volts at 33.3 times a second.