Difference between watts and volts

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ECURiley

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vv = driving 70mhp using your foot, drop in batterylife = driving up hill (drive up the volts to get the right power)
vw = driving 70mph using cruise control, drop in batterylife = driving up hill (no change)
look at ohms law to figure out what volts your are using when using vw, having the watts at 15 doesnt mean its going past 4.5v, it just means your are using a controlled power, different ohms at 15watts will give you differend volts
 

Fizzpop

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There is no real difference between a VV device and a VW device. See the equation below:

watt.png

Your resistance is constant, so the only thing you can change is the voltage. All a variable watt device does is to perform the calculation for you to determine how many volts you need to obtain the desired wattage.
 

Funk Dracula

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They are two different measurements. They do not "equal" each other.

Ohm's law - Wikipedia, the free encyclopedia

voltage - definition of voltage by the Free Online Dictionary, Thesaurus and Encyclopedia.

wattage - definition of wattage by the Free Online Dictionary, Thesaurus and Encyclopedia.

Think of VV versus VW like two different methods of heating a home in the winter. In both cases voltage is used, and the end result is wattage.

If it's colder (more resistance), you need to burn more gas in the furnace (volts), to get your home to a certain temperature (wattage.)

So, if this analogy is making any sense:

Wattage is like the end result, the "temperature". In the case of Variable Wattage, it is like setting an automated furnaces thermostat to a specific temperature. (wattage)

Voltage is like fire/heat. In the case of Variable Voltage, it is like measuring the temperature of your house, and them manually adjusting the flame of your furnace by hand to get to your desired temperature. You have to do it yourself, where in the case of an automated thermostat controlled furnace it is done for you as needed.

The varying degrees of winter cold is like the resistance of your coils.

If it's colder outside (higher resistance), you will need more fire/heat (voltage) to get your house to a desired temperature (wattage). (Let's say the desired temperature is 72˚)

If it's less cold outside (less resistance), you will need less fire/heat (voltage) to get your house to the desired temperature (wattage). (same 72˚ end result as above)

So you can see, depending on how cold it is outside, you needed different amounts of heat to keep your house at 72˚.

This is the best I could come up with guys...:p



Now being strictly mathematical, if we were to plug some numbers into this Ohm's Law calculator, vapecalc.com, and apply it to vaping:

A 2Ω coil on top of your device set to 4.2V will give you 8.82W.

A 1.3Ω coil on top of your device set to 4.2V will give you 13.57W.

To get the relatively same "temperature" experience from that 1.3Ω coil as you did on the 2Ω coil, you would need to lower your voltage down to about 3.4V.

What happens on a Variable Wattage device is that it measures the resistance of the coil, and automatically adjusts the voltage supplied to obtain the desired wattage you set.


Make sense???
 

LurkTron

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They are two different measurements. They do not "equal" each other.

Ohm's law - Wikipedia, the free encyclopedia

voltage - definition of voltage by the Free Online Dictionary, Thesaurus and Encyclopedia.

wattage - definition of wattage by the Free Online Dictionary, Thesaurus and Encyclopedia.

Think of VV versus VW like two different methods of heating a home in the winter. In both cases voltage is used, and the end result is wattage.

If it's colder (more resistance), you need to burn more gas in the furnace (volts), to get your home to a certain temperature (wattage.)

So, if this analogy is making any sense:

Wattage is like the end result, the "temperature". In the case of Variable Wattage, it is like setting an automated furnaces thermostat to a specific temperature. (wattage)

Voltage is like fire/heat. In the case of Variable Voltage, it is like measuring the temperature of your house, and them manually adjusting the flame of your furnace by hand to get to your desired temperature. You have to do it yourself, where in the case of an automated thermostat controlled furnace it is done for you as needed.

The varying degrees of winter cold is like the resistance of your coils.

If it's colder outside (higher resistance), you will need more fire/heat (voltage) to get your house to a desired temperature (wattage). (Let's say the desired temperature is 72˚)

If it's less cold outside (less resistance), you will need less fire/heat (voltage) to get your house to the desired temperature (wattage). (same 72˚ end result as above)

So you can see, depending on how cold it is outside, you needed different amounts of heat to keep your house at 72˚.

This is the best I could come up with guys...:p



Now being strictly mathematical, if we were to plug some numbers into this Ohm's Law calculator, vapecalc.com, and apply it to vaping:

A 2Ω coil on top of your device set to 4.2V will give you 8.82W.

A 1.3Ω coil on top of your device set to 4.2V will give you 13.57W.

To get the relatively same "temperature" experience from that 1.3Ω coil as you did on the 2Ω coil, you would need to lower your voltage down to about 3.4V.

What happens on a Variable Wattage device is that it measures the resistance of the coil, and automatically adjusts the voltage supplied to obtain the desired wattage you set.


Make sense???

Thank you for such a detailed answer. It makes sense now. Really appreciate the detail you went into. Your explanation was perfect.


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LurkTron

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vv = driving 70mhp using your foot, drop in batterylife = driving up hill (drive up the volts to get the right power)
vw = driving 70mph using cruise control, drop in batterylife = driving up hill (no change)
look at ohms law to figure out what volts your are using when using vw, having the watts at 15 doesnt mean its going past 4.5v, it just means your are using a controlled power, different ohms at 15watts will give you differend volts

Now is there a max amount of volts I could pump into a coil? Say 2.3 ohm at 5v? Would that be too much? I've seen the tables and what not but are there variables, say between a 10 wrap micro coil at 2 ohms vs a standard wrap at 2 ohm. Would one be able to take more volts. What would happen if too many volts were pumped into one of these coils. Battery discharging? Coils popping?


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UncleChuck

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That does seem odd you are having that issue.

If you had a 1.5 ohm coil, at 15 watts your device should put pumping 4.7 volts into your carto.

If you had a 2 ohm coil, at 15 watts you get 5.4 volts.

2.5 ohm is a little over 6v, device might not even fire this high.

3 ohm is about 6.7, the device definitely won't fire that high.

In all those scenarios the voltage applied is higher than the 4.5v that you say causes burning, which is why it seems a bid odd. If anything the 15 watts, regardless of carto resistance, should be burning juice more than the 4.5v because of the figures I posted above.

I'm not denying you are experiencing what you claim, but I suspect there is something else at work here. Are you using the same device, switching between voltage and wattage mode for testing, or are you using a separate VW device and a separate VV device? Because if the latter is the case there is a few things it could be:

The VV device is firing higher than it should be (set at 4.5, fires at 5.5 for example)

The VW device isn't firing as high as it should, so when set at 15 watts, you are getting substantially less, which by comparison would make the VV device seem to be firing higher.

It would help to know the device or devices you are using, specific resistance of attys or cartos, and battery configuration (single 18350, single 18650, dual 18350, etc)

EDIT:

After re-reading your post, it seems you are using rebuildables? If so it would be helpful to know the specifics of your build: wire gauge, resistance, type (spaced, compressed, micro) as well as wicking material. Are you experiencing burning on the same atty when switched between mods, or different attys?

If you are using rebuilables it's possible the burning is simple due to you setting the voltage too high.

If you have a 1 ohm coil set to 15 watts, that's only 3.9v or so. When you set it to 4.5v that's more power and voltage than your 15 watts, so it's possible your build just can't handle that much power.
 
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LurkTron

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That does seem odd you are having that issue.

If you had a 1.5 ohm coil, at 15 watts your device should put pumping 4.7 volts into your carto.

If you had a 2 ohm coil, at 15 watts you get 5.4 volts.

2.5 ohm is a little over 6v, device might not even fire this high.

3 ohm is about 6.7, the device definitely won't fire that high.

In all those scenarios the voltage applied is higher than the 4.5v that you say causes burning, which is why it seems a bid odd. If anything the 15 watts, regardless of carto resistance, should be burning juice more than the 4.5v because of the figures I posted above.

I'm not denying you are experiencing what you claim, but I suspect there is something else at work here. Are you using the same device, switching between voltage and wattage mode for testing, or are you using a separate VW device and a separate VV device? Because if the latter is the case there is a few things it could be:

The VV device is firing higher than it should be (set at 4.5, fires at 5.5 for example)

The VW device isn't firing as high as it should, so when set at 15 watts, you are getting substantially less, which by comparison would make the VV device seem to be firing higher.

It would help to know the device or devices you are using, specific resistance of attys or cartos, and battery configuration (single 18350, single 18650, dual 18350, etc)

EDIT:

After re-reading your post, it seems you are using rebuildables? If so it would be helpful to know the specifics of your build: wire gauge, resistance, type (spaced, compressed, micro) as well as wicking material. Are you experiencing burning on the same atty when switched between mods, or different attys?

If you are using rebuilables it's possible the burning is simple due to you setting the voltage too high.

If you have a 1 ohm coil set to 15 watts, that's only 3.9v or so. When you set it to 4.5v that's more power and voltage than your 15 watts, so it's possible your build just can't handle that much power.

I was switching between the mvp 1 and the vamo v5. I have a protank mini 2 rebuild with I think 10 wraps of 30 gauge coming out to about 2.3 ohms. It is indeed odd.


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LurkTron

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Air flow is your problem!

As far as the volts - watts BS, Ohms Law is a circle and there are always three formulas for getting from point A to point B.

ohmlaw.gif

I have the ohms law calculator. But how did you decide airflow is my problem? My air flow is pretty airy and there is not even a slight different of air flow between the 2 devices.


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dr g

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On a variable wattage device I can go 15 watts with mass amounts of vapor. But can't go past about 4.5 volts on a variable voltage device without getting a burnt taste and not nearly the amount of vapor production. Help please


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Need more info. Same atomizer? What devices exactly?
 

UncleChuck

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I was switching between the mvp 1 and the vamo v5. I have a protank mini 2 rebuild with I think 10 wraps of 30 gauge coming out to about 2.3 ohms. It is indeed odd.


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What battery were you using in the Vamo? 18350, 18650, dual 18350s? Because the Vamo and most other cheap variable devices won't reach 15 watts (or 6v) without stacking batteries. Meaning when your device is set to 15 watts, it's not actually putting out 15 watts. If you look at the Pbusardo review of the vamo you can see his scope charts which show the vamo falling off in the high end with a single cell.

If your vamo was actually putting out 15 watts with the 2.3 ohm coil, it would be producing about 5.8v, much higher than the 4.5 that you say caused burning with the MVP. The MVP uses a more powerful battery than the single cell in your Vamo, lipo packs I believe, so when you set it to 4.5v it's producing a TRUE 4.5v, causing the burnt taste.

The solution is to simply turn the voltage down a bit. You could also stack batteries in your Vamo and experience the full power of that device as well (although maybe not if you're burning juice with the MPV ;) )

I suspect there might be an issue with your build though, since we are dealing with less than 9 watts here, using 30g you should be able to get well past 10 watts before you start burning juice. Perhaps a hot leg scorching the grommet around the positive pin, if that's the case it's best to replace it with a silicone one.
 
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tj99959

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    I have the ohms law calculator. But how did you decide airflow is my problem? My air flow is pretty airy and there is not even a slight different of air flow between the 2 devices.


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    Because if the power (volts/watts) are in fact the same, the only thing that would be different would be the air flow through the connector.
     
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