RMS vs MEA

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SilverZero

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I'm certainly not an expert, but this is my understanding of it.

mods like the Zmax and the VAMO use pulse width modulation to output their electrical signals. For example, if you set your voltage to 3.7V the unit doesn't fire a constant 3.7V while you press the button; instead, the coil is turned on and off extremely fast. The resulting wave oscillates from 0V up to say 4.5V, but because the signal is turning on and off rapidly it averages out to 3.7V. As you turn the voltage setting up the mod doesn't output a higher voltage to the coil; instead, it increases the percentage of the time that the signal is turned on, and because it is turned on more often the average voltage goes up (and vice versa if you turn down the voltage setting).

RMS and mean are simply two different ways to calculate the average output of that fluctuating signal. RMS is a more complex calculation but it more accurately reflects the setting that you select. If you use a mean calculation the output voltage may be higher than your desired voltage, expecially at low settings. That can be a problem, because the Zmax might actually be sending more voltage to your coil than you want it to.

Because of the confusion with these settings some new mods like the VAMO V3 have removed the mean option altogether.

Hopefully that helps a little. I'm sure if I got something wrong (likely) someone here will correct me.
 

jward015

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I'm certainly not an expert, but this is my understanding of it.

Mods like the Zmax and the VAMO use pulse width modulation to output their electrical signals. For example, if you set your voltage to 3.7V the unit doesn't fire a constant 3.7V while you press the button; instead, the coil is turned on and off extremely fast. The resulting wave oscillates from 0V up to say 4.5V, but because the signal is turning on and off rapidly it averages out to 3.7V. As you turn the voltage setting up the mod doesn't output a higher voltage to the coil; instead, it increases the percentage of the time that the signal is turned on, and because it is turned on more often the average voltage goes up (and vice versa if you turn down the voltage setting).

RMS and mean are simply two different ways to calculate the average output of that fluctuating signal. RMS is a more complex calculation but it more accurately reflects the setting that you select. If you use a mean calculation the output voltage may be higher than your desired voltage, expecially at low settings. That can be a problem, because the Zmax might actually be sending more voltage to your coil than you want it to.

Because of the confusion with these settings some new mods like the VAMO V3 have removed the mean option altogether.

Hopefully that helps a little. I'm sure if I got something wrong (likely) someone here will correct me.


Great explanation!
 

SilverZero

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I'm also kind of wondering about wattage vs voltage. I know W=vsquared over R but doesn't that kind of make it the same thing in different terms?

You can achieve a quality vape using either setting, but variable power works more like a "set it and forget it" option. If you are using variable voltage you will need to change your power setting based on the resistance of the atomizer that is attached; variable power takes the resistance of that atty into account in order to output the same power no matter what is attached.

Right now I have a 2.0 ohm Protank on my VAMO, and the power setting is set to 7.5 watts. If I remove the protank and attach my 1.4 ohm dripping atomizer I don't need to change the power setting to get the vape that I want. It's pretty neat when you think about it.
 

eHuman

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Our advanced MODs use PWM (pulse width modulation). The on and off cycle time stays the same, but depending on the set-point, the "voltage time on" portion varies.

RMS (square Root of the Mean(or average), Squared) uses a more accurate logarithm to achieve and maintain the desired set-point than AVG mode can.

AVG is excellent for use with constant output voltage power supplies, RMS is excellent for use with PWM power supplies.
Using AVG mode with PWM results in a much higher output than desired.
 

BeatboxHero

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Jul 26, 2013
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Just like everyone else, I own a Zmax or two; okay make it five of them. However I always leave the eighth setting on Root Mean Average just because I've heard it vaporizes more efficiently. But I don't exactly know what the difference is between RMS and MEA, could someone explain?

SilverZero has pretty much rapped everything up here :2cool: But I did want to say that I recently switched from an eGo to a Zmax and RMS is the way to go! I had the eGo-V V2 Mega which was a VV eGo. I would vape juice in my Protank with a 2.5 Ohm coil at about 5-6 volts. That hit the best for me. But then I bought my Zmax and through the exact same Protank on it and at 5-6 volts it tasted like it was burning my liquid! :mad: I would then put the same tank back on my eGo and it was fine at that voltage. No burn at all.

Now there are 2 things happening here. I am certain my eGo was putting out LESS then 5-6 volts at some point. But even at "full charge" it worked great. No burnt taste. So then I put my Zmax on RMS and it fixed everything! I did eventually switch over to Power mode since, like SilverZero said, it is way easier and you don't need to adjust as often. But burning at 5-6 volts had no burn at all! So what I have experienced is that RMS is way more accurate. What is on your display is what you are actually vaping at :vapor: On MEAN setting you are going over what you are set too.
 

Gargy777

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Jul 22, 2012
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Had the same issue as you BeatBox except with my Vamo V3. Somehow I got one of the V3s that has RMS and Mean so ofc mine came defaulted to Mean and everything was getting burnt even at the lowest settings. Like you I also tried going back to my Twist and things were ok so I was puzzled. Thankfully last night I checked out PBusardo's review of the Vamo V5 and lo and behold my Vamo was in Mean mode. It's working fine now that I've switched it RMS.

Also, thx to Silver's post I was able to deduce that you set the wattage OR the voltage. I thought you had to set them both. It's funny how just yesterday I thought I knew exactly how to use my Vamo but turns out I really had no idea :).
 
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