Burning Cartomisers? Dangerous?-510/Kr808/4081...etc filler type cartos
- Thread starter dougp925
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Yes you are.
Always have been, always will be!
So glad to hear some good news from you! And you sound happier today!
Okay, okay. I'm taking care of myself. Was recently able to do away with with the leg bag that emptied my left kidney. Still have the tube in my back for it, but it can now empty into my bladder. Hope to get rid of it and the catheter in about a month.
I remember that guy!
Good! Baby steps!
Per Kat's request. Stashed here:
Volts, Ohms, Watts, and Amps.
E-cigs introduce you to terms that you probably wouldn't use everyday without them. Yet, you need to understand some of them, in order to wade through the sites and options and understand the effect of your choices. This post discusses the electrical terms in particular; volts, ohms, watts and amps. The good news is...it isn't really that bad. The bad news is that it isn't a 2 second discussion.
The short answer is that if you have a Variable-Voltage (VV) or Variable Wattage (VW) device, you can just start low, dial it up, and make it work. No math required. Non-adjustable voltage PVs require you to select the proper ohm coil ahead of time.
However, if you want to UNDERSTAND how and why the ohms affect the heat, for example, that will take some work on your part. It's not too bad, but it's also something that you don't want to try to cram into a 2 minute reading. You may have to read this a couple of times. That's fine. Don't give up. If you really can't stand reading...skip to part 3.
Part 1 - coming to terms with it
OK let's get some terms straight first:
Volts = Electrical Pressure. Kind of like water pressure.
Ohms = Friction. Resistance to the flow of electricity. Without friction, we'd have no heat in our coils. Like a kink in a water hose.
Amps (amperes) = total electrons flowing past a point. Similar to the volume of water (# of molecules?) going past a point in the hose at one particular instant.
Watts = A measure of "work". Watts = Volts X Amps. How fast it could turn a water wheel.
Watts are kind of an "end-result". No work is done if there's no pressure. Also no work is done if there's no volume of water flowing. You have to have pressure and water flow to get an effective amount of water on the lawn from a sprinkler. High pressure with a very thin hose won't do it. Neither will no pressure with a fat fire-hose. You have to have volume and pressure at the same time. The constriction of a hose is a resistance (like ohms), and determines the flow rate for a given pressure.
All of these things are interrelated. If you change any one thing, the system as a whole is changed. In fact, if you know any two of the above variables, you can calculate the others. They are measurements for different aspects of a particular system. All pieces of the same puzzling phenomenon.
Volts, ohms, watts and amps are quantities that can be measured and related mathematically. That leads to the inevitable formulas....
Part 2 - Finally! Some math. Yay! (or OMG! I hate this stuff.)
Because volts, ohms, and amps are measurable quantities, someone took a lot of measurements of them and figured out how they all relate. The results of this relationship became "Ohm's Law" of electricity. The law was named after the German physicist Georg Ohm, who published them in the early 1800's. Thanks to James Prescott Joule there's also Joule's Law: Watts = Volts x Amps but we're getting ahead.
Now quantities measured need names for them. Feet, meters, pounds, grams are all units of measure. Some of the units of measure for electricity are defined above: Volts, ohms, watts, amps. We have abbreviations for them so we can use them in formulas. The bad news is that you'll see several versions of these abbreviations. The good news is that we'll try to tell you the common ones so you can substitute whatever version you like.
Abbreviations:
Volts = V = E = (Straight line with little dots under it symbol for DC voltage)
Ohms = R = Ω = Resistance
Amps = I = A
Watts = P = W = Power
It's very irritating when you see one set of formulas published here, and another set somewhere else that uses different letters or symbols. Your multi-meter (the tool used to measure these things) often uses a different set too. Yet we have to pick one set. No matter what we select, someone's not going to like it...depending on if they are a "purest" or of they are in the commonly-seen camp. We'll use V for volts, R for ohms (resistance), I for Amps (because A is used for something else except on multi-meters), and P for watts (Power).
OK, so this guy Ohm published a "law" that is stated in modern form as:
Amps = Volts ÷ Ohms or I = V ÷ R
Add in Joule's Law: Watts = Volts X Amps or P = VI
Mathematicians, having nothing better to do than math, re-arranged all this stuff and came up with a list of formulas
Amps (I) = V ÷ R, also I = P ÷ V and I = Square-Root of (P ÷ R)
Volts (V) = I X R, also V = P ÷ I and V = Square-Root of (P X R)
Ohms (R) = V ÷ I, also R = V2 ÷ P and R = P ÷ I2
Watts (P) = V X I, also P = R X I2 and P = V2 ÷ R
OK. So the formulas are listed above. What does all this have to do with e-cigs?
Part 3 - Getting to the point, now that we have background and formulas.
You, a user of e-cigs, are basically juggling multiple variables related to electricity. Sure, there's other stuff too...e-juice VG/PG ratios, wicking, etc. but we're discussing electricity here. The point is that there's no ONE variable...there's always multiple things going on at once. Selecting a PV has electrical concerns too...for example the "amp limit" of the device. Swapping a carto out with different ohms means that you'll adjust the voltage (for VV stuff) or deal with the results for fixed-voltage stuff. VW adjusts voltage for you...like it or not.
To reiterate, you can't change one thing without it affecting the others somehow. So here's where we try to explain how what you do effects things. Also, note that this is not an e-cig safety thread. So we try to explain some things, but safety is another subject unto itself. Don't take this as gospel. We're trying to teach general concepts here.
Voltage...the Oomph factor
You have one of three types of PV's
1) Fixed voltage. They are "regulated" to a speific set voltage. They may dwindle below it before cutting out, but they are still "fixed" in that you can't adjust them. They are regulated though....electronic circuits inside attempt to make the voltage the same regardless of the battery charge. Some only do this when the battery is above the set voltage limit.
2) Variable voltage. Adjustable voltage (also adjustable wattage) e-cigs have circuitry to bump-up (boost) or regulate down (buck) battery voltage according to a dial that you set. Variable Wattage (VW) e-cigs read the resistance of the coil you've screwed onto the connector and calculate the voltage you need to acheive a desired wattage setting. So they adjust the voltage for you.
3) Follows battery voltage - ie two wires, a battery, and a connector. Vaping directly off the battery at whatever voltage it has at the moment. Typical for all-mechanical mods. Li-Ion (and that class of batteries including IMR) have a top voltage of about 4.2 volts but they drop quickly to about 3.7/3.6 volts and stay in that rage for most of the usable charge and then drop quickly below that to cut-off voltage.
Each of these types come in either swappable battery configurations (where you have a "cell" that you can remove) or internal battery configurations where you charge the whole unit somehow and cannot remove the battery from the electronics/mechanics.
How do you make a fixed voltage e-cig hotter or cooler? By selecting the proper ohm coil. It's the only "variable" that you can change. The voltage is fixed. And as we've learned above, if any two factors are known, all factors are set. So the heat will be P = V2 ÷ R (or Watts = Voltage squared divided by coil ohms) for a single coil. So if you want to vape at 8 watts, and you know the voltage of your fix-volt e-cig...use R = V2 ÷ P (voltage squared divided 8). A 3.7 volt e-cig needs 3.7 x 3.7 / 8 = 1.71125 ohms to get 8 watts. Of course, there's wiggle room. And in fact coil ohms vary a bit due to manufacturing variability. 2.0 ohms will work. 3.0 ohms is not that good. 1.5 ohms may even be a bit hot. On the other hand, some e-cigs are 3.4 volts (like the original authentic eGo) and they may do better at 1.5 ohms.
How do you make a VV, or VW e-cig hotter or cooler....by adjust the dial, of course! The difference is that with VW, it will "sense" the ohms of the coil that you have screwed on and calculate the proper voltage...assuming you don't fake it out with the dual-coil thing. More on DC (dual coil) stuff later. Due to differences in devices and coils, you may have to adjust VW a bit anyway. But it gets you into the ballpark regardless of what ohm coil you screw on.
So for regulated fixed voltage stuff, or for follow-battery-voltage stuff, you must select the proper ohms ahead of time...there's no adjustment for the voltage/wattage on the e-cig. Get it wrong, and it's too hot or too cool. It's not super picky though...there's a workable range of ohms within reason.
Wattage
You know wattage. It's like incandescent light-bulbs. More wattage = more energy used = hotter/brighter. It's the result of the voltage and the coil ohms per the formula above. Watts = heat for our purposes. Normal ranges are about 7-9 watts per coil. This is for "normal" coils. There are dual coils ...where the PV must supply double the current (amps) in order to keep the voltage high enough for two coils. Think of it like a two lane toll booth on a toll road allowing double the cars through at once. Electrons per second past a point = amps (current). So more amps are required for dual coils at any given voltage.
The watts for dual coils are, not surprisingly, doubled for the device as a whole. If each coil is 8 watts, you need to supply a dual coil with 16 watts total. This is why dual-coil users often run up against amp limits on their devices. The device exceeds it's expected amp draw and either signals a "short" or drops the voltage to compensate for lack of amps. It won't work as expected, if at all, unless your PV can supply the amps at whatever voltage you set.
For VW devices...just set the wattage. For VV only devices...calculate the voltage or just start low and adjust higher as needed. To calculate the voltage:
So for single coils: Try 7-9 watts as a ballpark/average. Let's say 8. So voltage = Square-Root of (P X R) = Square-Root of (8 X ohms)
For dual coils: double the ohms 1st. A 1.5 ohm dual coil is really two 3.0 ohm coils side-by-side on the same connector. So the voltage is calculated for 3.0 ohms, NOT the 1.5 ohms. So around 5 volts should be good for a 1.5 ohm DC at 8 watts per coil. Because the square root of 24 (3 ohms times 8 watts) is about 5 (OK....4.898979485566356
amp limits
SLR
Symbols on multimeters
What about:
mAh?
Series vs Parallel (or covered under DCC)
Battery stuff or link to Battery University.
Hi there AttyPops. I don't know if Tweetie Pie can handle that much in one sitting
.I like the Variable-Voltage method of start low and dial it up. That's what I had Peggy do and it works fine for her.
About fixed voltage. I can't say for certain about everything that is available now, but some of the 3.7 volt batteries that I knew of were not regulated. For instance, the KR801D. It starts out as 3.7 volts and maintains it for as long as possible, then tappers off to the recharge voltage. Maybe it's different now. damfino
Hi there AttyPops. I don't know if Tweetie Pie can handle that much in one sitting
Hey!
I like Variable Wattage better.
Some are unregulated, some claim to be regulated at 3.4-3.5v, but I don't quite believe them.
And they have a new dual-mode eGo battery--you can run it in a regulated 3.3v mode or 3.7v unregulated.
Hey!
I like Variable Wattage better.
Some are unregulated, some claim to be regulated at 3.4-3.5v, but I don't quite believe them.
And they have a new dual-mode eGo battery--you can run it in a regulated 3.3v mode or 3.7v unregulated.
Variable voltage, wattage and every thing else. The battery is doing the same thing for all of them. You just read it different. As far as I am concerned, all that display stuff just adds to the size and cost of the battery. KISS
I've learned not to trust most advertised voltages, but I think the one about the eGo battery is correct.
We got another DVD from Netflix today, so Peggy and I are headed for the TV in the bedroom. Catch you kids later.
Hi there AttyPops. I don't know if Tweetie Pie can handle that much in one sitting
I like the Variable-Voltage method of start low and dial it up. That's what I had Peggy do and it works fine for her.
About fixed voltage. I can't say for certain about everything that is available now, but some of the 3.7 volt batteries that I knew of were not regulated. For instance, the KR801D. It starts out as 3.7 volts and maintains it for as long as possible, then tappers off to the recharge voltage. Maybe it's different now. damfino
That's what type 3 is intended for I guess... "Follows battery voltage". However, maybe we need to be more clear about all that. It's hard to put all this stuff into words.
We'll also break it up into sections. However, it's one long post now because it's easy to cut-paste-edit.
Keep commenting! We can use the editing help too. Hang in there! Hope you're feeling better.
That's what type 3 is intended for I guess... "Follows battery voltage". However, maybe we need to be more clear about all that. It's hard to put all this stuff into words.
We'll also break it up into sections. However, it's one long post now because it's easy to cut-paste-edit.
Keep commenting! We can use the editing help too. Hang in there! Hope you're feeling better.
Yeah, it's hard to put this stuff in a few words. Some books have whole chapters on each of these subjects.
For my way of thinking, type 1 should be named "Regulated Voltage" instead of "Fixed Voltage" and type 3 should should be "Fixed Voltage" instead of "Follows battery voltage".
All batteries have a fixed voltage, but they can be regulated at a specific lower voltage with a simple circuit, or they can be regulated at various lower voltages with added circuitry. They can also be regulated at a higher voltage with a more complicated boost circuit. An even more sophisticated circuit can regulate and vary these voltages above and below the battery's fixed voltage.
All batteries have a rated voltage and when fully charged they will supply a suitable load at that that voltage. However, all of them will measure a higher voltage without a load applied. This holds true for a simple 1 1/2 volt flashlight cell or any other battery, be it rechargeable or non-rechargeable.
For instance, most of our e-cig batteries are rated at 3.7 volts and they will measure about that while in actual use. However, they are charged to 4.2 volts and will measure about that without a load applied. Anyone who calls them a 4.2 battery is either ignorant or a liar. We don't say our car batteries are 13.6 volts, do we? No, we say they are 12 volts, but actually they are 12.6 volts, heheh.
By the same token, the available voltages of our variable batteries should not be measured without a load, but they often are by vendors and manufacturers. That leaves us not knowing what we actually have unless we have the equipment to test them for ourselves.
Some regulated batteries have a reasonable circuit and some don't. For instance, the original 180 mAh 510 battery had it right. It is a 3.7 volt battery and regulates at about 3.2 volts or less. This gives it about a 0.5 volt headroom, which means it will hold the regulated voltage until the charge is almost depleted. Not so with the E-Power battery. It regulates at 3.5 volts with only a headroom of 0.2 volts. This means that it will quit regulating long before the charge is depleted. Headroom is why I like my 1300 mAh batteries. They regulate at about 3.0 volts and hang in there until almost charging time.
Of course, batteries with a single regulated voltage must have heating coils with the correct resistance. You kids who try everything new about as often as I change my socks need great big expensive batteries with all kinds of bells and whistles to find that sweet spot. But then, I'm old fashioned about the sweet spot. I thought it was something else until I began vaping.
We should probably just quote all that....minus the last 2 sentences maybe...
It gets to be a long explanation quickly.
We should probably just quote all that....minus the last 2 sentences maybe...
It gets to be a long explanation quickly.
That will be okay by me, give or take a lie or two.
And you wouldn't believe what I used to think burning cartomizer was a euphenism for.
Good to see you BR. This aging businesss can be a pain in the youknowwhat can't it?
Last edited:
And you wouldn't believe what I used to think burning cartomizer was a euphenism for.
Good to see you BR. This aging businesss can be a pain in the youknowwhat can't it?
I had a sneaky feeling that you would reply to this one, heheh.
Per Kat's request. Stashed here:
Updated with mAh stuff. Not sure how to incorporate BR's info yet. May have to figure out how we'll break it all up 1st...
Volts, Ohms, Watts, and Amps.
E-cigs introduce you to terms that you probably wouldn't use everyday without them. Yet, you need to understand some of them, in order to wade through the sites and options and understand the effect of your choices. This post discusses the electrical terms in particular; volts, ohms, watts and amps. The good news is...it isn't really that bad. The bad news is that it isn't a 2 second discussion.
The short answer is that if you have a Variable-Voltage (VV) or Variable Wattage (VW) device, you can just start low, dial it up, and make it work. No math required. Non-adjustable voltage PVs require you to select the proper ohm coil ahead of time.
However, if you want to UNDERSTAND how and why the ohms affect the heat, for example, that will take some work on your part. It's not too bad, but it's also something that you don't want to try to cram into a 2 minute reading. You may have to read this a couple of times. That's fine. Don't give up. If you really can't stand reading...skip to part 3.
Part 1 - coming to terms with it
OK let's get some terms straight first:
Volts = Electrical Pressure. Kind of like water pressure.
Ohms = Friction. Resistance to the flow of electricity. Without friction, we'd have no heat in our coils. Like a kink in a water hose.
Amps (amperes) = total electrons flowing past a point. Similar to the volume of water (# of molecules?) going past a point in the hose at one particular instant.
Watts = A measure of "work". Watts = Volts X Amps. How fast it could turn a water wheel.
Watts are kind of an "end-result". No work is done if there's no pressure. Also no work is done if there's no volume of water flowing. You have to have pressure and water flow to get an effective amount of water on the lawn from a sprinkler. High pressure with a very thin hose won't do it. Neither will no pressure with a fat fire-hose. You have to have volume and pressure at the same time. The constriction of a hose is a resistance (like ohms), and determines the flow rate for a given pressure.
All of these things are interrelated. If you change any one thing, the system as a whole is changed. In fact, if you know any two of the above variables, you can calculate the others. They are measurements for different aspects of a particular system. All pieces of the same puzzling phenomenon.
Volts, ohms, watts and amps are quantities that can be measured and related mathematically. That leads to the inevitable formulas....
Part 2 - Finally! Some math. Yay! (or OMG! I hate this stuff.)
Because volts, ohms, and amps are measurable quantities, someone took a lot of measurements of them and figured out how they all relate. The results of this relationship became "Ohm's Law" of electricity. The law was named after the German physicist Georg Ohm, who published them in the early 1800's. Thanks to James Prescott Joule there's also Joule's Law: Watts = Volts x Amps but we're getting ahead.
Now quantities measured need names for them. Feet, meters, pounds, grams are all units of measure. Some of the units of measure for electricity are defined above: Volts, ohms, watts, amps. We have abbreviations for them so we can use them in formulas. The bad news is that you'll see several versions of these abbreviations. The good news is that we'll try to tell you the common ones so you can substitute whatever version you like.
Abbreviations:
Volts = V = E = (Straight line with little dots under it symbol for DC voltage)
Ohms = R = Ω = Resistance
Amps = I = A
Watts = P = W = Power
It's very irritating when you see one set of formulas published here, and another set somewhere else that uses different letters or symbols. Your multi-meter (the tool used to measure these things) often uses a different set too. Yet we have to pick one set. No matter what we select, someone's not going to like it...depending on if they are a "purest" or of they are in the commonly-seen camp. We'll use V for volts, R for ohms (resistance), I for Amps (because A is used for something else except on multi-meters), and P for watts (Power).
OK, so this guy Ohm published a "law" that is stated in modern form as:
Amps = Volts ÷ Ohms or I = V ÷ R
Add in Joule's Law: Watts = Volts X Amps or P = VI
Mathematicians, having nothing better to do than math, re-arranged all this stuff and came up with a list of formulas (note the X here means multiply...it's not a variable):
Amps (I) = V ÷ R, also I = P ÷ V and I = Square-Root of (P ÷ R)
Volts (V) = I X R, also V = P ÷ I and V = Square-Root of (P X R)
Ohms (R) = V ÷ I, also R = V2 ÷ P and R = P ÷ I2
Watts (P) = V X I, also P = R X I2 and P = V2 ÷ R
OK. So the formulas are listed above. What does all this have to do with e-cigs?
Part 3 - Getting to the point, now that we have background and formulas.
You, a user of e-cigs, are basically juggling multiple variables related to electricity. Sure, there's other stuff too...e-juice VG/PG ratios, wicking, etc. but we're discussing electricity here. The point is that there's no ONE variable...there's always multiple things going on at once. Selecting a PV has electrical concerns too...for example the "amp limit" of the device. Swapping a carto out with different ohms means that you'll adjust the voltage (for VV stuff) or deal with the results for fixed-voltage stuff. VW adjusts voltage for you...like it or not.
To reiterate, you can't change one thing without it affecting the others somehow. So here's where we try to explain how what you do effects things. Also, note that this is not an e-cig safety thread. So we try to explain some things, but safety is another subject unto itself. Don't take this as gospel. We're trying to teach general concepts here.
Voltage...the Oomph factor
You have one of three types of PV's
1) Fixed voltage. They are "regulated" to a speific set voltage. They may dwindle below it before cutting out, but they are still "fixed" in that you can't adjust them. They are regulated though....electronic circuits inside attempt to make the voltage the same regardless of the battery charge. Some only do this when the battery is above the set voltage limit.
2) Variable voltage. Adjustable voltage (also adjustable wattage) e-cigs have circuitry to bump-up (boost) or regulate down (buck) battery voltage according to a dial that you set. Variable Wattage (VW) e-cigs read the resistance of the coil you've screwed onto the connector and calculate the voltage you need to acheive a desired wattage setting. So they adjust the voltage for you.
3) Follows battery voltage - ie two wires, a battery, and a connector. Vaping directly off the battery at whatever voltage it has at the moment. Typical for all-mechanical mods. Li-Ion (and that class of batteries including IMR) have a top voltage of about 4.2 volts but they drop quickly to about 3.7/3.6 volts and stay in that rage for most of the usable charge and then drop quickly below that to cut-off voltage.
Each of these types come in either swappable battery configurations (where you have a "cell" that you can remove) or internal battery configurations where you charge the whole unit somehow and cannot remove the battery from the electronics/mechanics.
How do you make a fixed voltage e-cig hotter or cooler? By selecting the proper ohm coil. It's the only "variable" that you can change. The voltage is fixed. And as we've learned above, if any two factors are known, all factors are set. So the heat will be P = V2 ÷ R (or Watts = Voltage squared divided by coil ohms) for a single coil. So if you want to vape at 8 watts, and you know the voltage of your fix-volt e-cig...use R = V2 ÷ P (voltage squared divided 8). A 3.7 volt e-cig needs 3.7 x 3.7 / 8 = 1.71125 ohms to get 8 watts. Of course, there's wiggle room. And in fact coil ohms vary a bit due to manufacturing variability. 2.0 ohms will work. 3.0 ohms is not that good. 1.5 ohms may even be a bit hot. On the other hand, some e-cigs are 3.4 volts (like the original authentic eGo) and they may do better at 1.5 ohms.
How do you make a VV, or VW e-cig hotter or cooler....by adjust the dial, of course! The difference is that with VW, it will "sense" the ohms of the coil that you have screwed on and calculate the proper voltage...assuming you don't fake it out with the dual-coil thing. More on DC (dual coil) stuff later. Due to differences in devices and coils, you may have to adjust VW a bit anyway. But it gets you into the ballpark regardless of what ohm coil you screw on.
So for regulated fixed voltage stuff, or for follow-battery-voltage stuff, you must select the proper ohms ahead of time...there's no adjustment for the voltage/wattage on the e-cig. Get it wrong, and it's too hot or too cool. It's not super picky though...there's a workable range of ohms within reason.
Wattage
You know wattage. It's like incandescent light-bulbs. More wattage = more energy used = hotter/brighter. It's the result of the voltage and the coil ohms per the formula above. Watts = heat for our purposes. Normal ranges are about 7-9 watts per coil. This is for "normal" coils. There are dual coils ...where the PV must supply double the current (amps) in order to keep the voltage high enough for two coils. Think of it like a two lane toll booth on a toll road allowing double the cars through at once. Electrons per second past a point = amps (current). So more amps are required for dual coils at any given voltage.
The watts for dual coils are, not surprisingly, doubled for the device as a whole. If each coil is 8 watts, you need to supply a dual coil with 16 watts total. This is why dual-coil users often run up against amp limits on their devices. The device exceeds it's expected amp draw and either signals a "short" or drops the voltage to compensate for lack of amps. It won't work as expected, if at all, unless your PV can supply the amps at whatever voltage you set.
For VW devices...just set the wattage. For VV only devices...calculate the voltage or just start low and adjust higher as needed. To calculate the voltage:
So for single coils: Try 7-9 watts as a ballpark/average. Let's say 8. So voltage = Square-Root of (P X R) = Square-Root of (8 X ohms)
For dual coils: double the ohms 1st. A 1.5 ohm dual coil is really two 3.0 ohm coils side-by-side on the same connector. So the voltage is calculated for 3.0 ohms, NOT the 1.5 ohms. So around 5 volts should be good for a 1.5 ohm DC at 8 watts per coil. Because the square root of 24 (3 ohms times 8 watts) is about 5 (OK....4.898979485566356)
Milliamp Hours (mAh)
You get billed on your electric bill by Kilowatt hours. That's the # of (thousands of) watts used for an hour. Note that there's an amount and a duration. A 2000 watt heater run for exactly one hour is 2 KWh. In the USA that's about 22 cents worth of energy, depending on location. So what is a Milliamp hour? Well, a milli-amp is 1000th of an amp. Thus 1/1000th of an amp run for 1 hour. An e-cig battery rated at 650 mAh can run 650/1000ths of an amp for an hour (well, not exactly, but electronics are usually using very small loads so that's how they are rated...in mAh).
However, that heater is dang cheap when you consider how hard it is to stuff that much energy into an e-cig battery. That would be a 1,000,000 mAh battery. See? lol. It's hard to stuff electrons into a battery. And we never have enough capacity.
So mAh is a capacity measurement. Like the size of a gas tank. Or the amount of water in a full water tower. I suppose you could give them a # of electrons difference between poles rating, but it's a crazy big number. Just remember that mAh is a capacity estimate....it gives you a rough idea of how much energy is stored in the battery for use over time.
Just like you can't predict how far an arbitrary car will drive by knowing the size of the tank alone (you'd also need to know the engine's MPG and the weight, and the amount of idling...etc) you can't predict how long a battery can be used without knowing the "load" on the battery. There is a common "rough guess" figure floating around here that every 100 mAh of battery capacity = approximately 1 hour of average vaping time. Even that varies quite a bit, because device designs, coils, and personal vaping usage vary quite a bit. And so do the mAh rating accuracies of the batteries. Some manufacturers seem to be more...accurate...than others. Ahem.
However, it still gives you a rough idea of the capacity of a battery when compared to another similar device used with the same coil by the same person.
Note that the safer chemistry of the IMR batteries has a trade-off in slightly lower storage capacity as compared to Li-Ion. However there are "hybrids" that use other chemistry that's somewhere in between. And ...it's an art and a science...even designing these things. There are new developments on the horizon all the time. So keep up to date and double check current information as this post becomes more out of date.
amp limits
SLR
Symbols on multimeters
What about:
mAh?
Series vs Parallel (or covered under DCC)
Battery stuff or link to Battery University.
Updated with mAh stuff. Not sure how to incorporate BR's info yet. May have to figure out how we'll break it all up 1st...
Volts, Ohms, Watts, and Amps.
E-cigs introduce you to terms that you probably wouldn't use everyday without them. Yet, you need to understand some of them, in order to wade through the sites and options and understand the effect of your choices. This post discusses the electrical terms in particular; volts, ohms, watts and amps. The good news is...it isn't really that bad. The bad news is that it isn't a 2 second discussion.
The short answer is that if you have a Variable-Voltage (VV) or Variable Wattage (VW) device, you can just start low, dial it up, and make it work. No math required. Non-adjustable voltage PVs require you to select the proper ohm coil ahead of time.
However, if you want to UNDERSTAND how and why the ohms affect the heat, for example, that will take some work on your part. It's not too bad, but it's also something that you don't want to try to cram into a 2 minute reading. You may have to read this a couple of times. That's fine. Don't give up. If you really can't stand reading...skip to part 3.
Part 1 - coming to terms with it
OK let's get some terms straight first:
Volts = Electrical Pressure. Kind of like water pressure.
Ohms = Friction. Resistance to the flow of electricity. Without friction, we'd have no heat in our coils. Like a kink in a water hose.
Amps (amperes) = total electrons flowing past a point. Similar to the volume of water (# of molecules?) going past a point in the hose at one particular instant.
Watts = A measure of "work". Watts = Volts X Amps. How fast it could turn a water wheel.
Watts are kind of an "end-result". No work is done if there's no pressure. Also no work is done if there's no volume of water flowing. You have to have pressure and water flow to get an effective amount of water on the lawn from a sprinkler. High pressure with a very thin hose won't do it. Neither will no pressure with a fat fire-hose. You have to have volume and pressure at the same time. The constriction of a hose is a resistance (like ohms), and determines the flow rate for a given pressure.
All of these things are interrelated. If you change any one thing, the system as a whole is changed. In fact, if you know any two of the above variables, you can calculate the others. They are measurements for different aspects of a particular system. All pieces of the same puzzling phenomenon.
Volts, ohms, watts and amps are quantities that can be measured and related mathematically. That leads to the inevitable formulas....
Part 2 - Finally! Some math. Yay! (or OMG! I hate this stuff.)
Because volts, ohms, and amps are measurable quantities, someone took a lot of measurements of them and figured out how they all relate. The results of this relationship became "Ohm's Law" of electricity. The law was named after the German physicist Georg Ohm, who published them in the early 1800's. Thanks to James Prescott Joule there's also Joule's Law: Watts = Volts x Amps but we're getting ahead.
Now quantities measured need names for them. Feet, meters, pounds, grams are all units of measure. Some of the units of measure for electricity are defined above: Volts, ohms, watts, amps. We have abbreviations for them so we can use them in formulas. The bad news is that you'll see several versions of these abbreviations. The good news is that we'll try to tell you the common ones so you can substitute whatever version you like.
Abbreviations:
Volts = V = E = (Straight line with little dots under it symbol for DC voltage)
Ohms = R = Ω = Resistance
Amps = I = A
Watts = P = W = Power
It's very irritating when you see one set of formulas published here, and another set somewhere else that uses different letters or symbols. Your multi-meter (the tool used to measure these things) often uses a different set too. Yet we have to pick one set. No matter what we select, someone's not going to like it...depending on if they are a "purest" or of they are in the commonly-seen camp. We'll use V for volts, R for ohms (resistance), I for Amps (because A is used for something else except on multi-meters), and P for watts (Power).
OK, so this guy Ohm published a "law" that is stated in modern form as:
Amps = Volts ÷ Ohms or I = V ÷ R
Add in Joule's Law: Watts = Volts X Amps or P = VI
Mathematicians, having nothing better to do than math, re-arranged all this stuff and came up with a list of formulas
(note the X here means multiply...it's not a variable):Amps (I) = V ÷ R, also I = P ÷ V and I = Square-Root of (P ÷ R)
Volts (V) = I X R, also V = P ÷ I and V = Square-Root of (P X R)
Ohms (R) = V ÷ I, also R = V2 ÷ P and R = P ÷ I2
Watts (P) = V X I, also P = R X I2 and P = V2 ÷ R
OK. So the formulas are listed above. What does all this have to do with e-cigs?
Part 3 - Getting to the point, now that we have background and formulas.
You, a user of e-cigs, are basically juggling multiple variables related to electricity. Sure, there's other stuff too...e-juice VG/PG ratios, wicking, etc. but we're discussing electricity here. The point is that there's no ONE variable...there's always multiple things going on at once. Selecting a PV has electrical concerns too...for example the "amp limit" of the device. Swapping a carto out with different ohms means that you'll adjust the voltage (for VV stuff) or deal with the results for fixed-voltage stuff. VW adjusts voltage for you...like it or not.
To reiterate, you can't change one thing without it affecting the others somehow. So here's where we try to explain how what you do effects things. Also, note that this is not an e-cig safety thread. So we try to explain some things, but safety is another subject unto itself. Don't take this as gospel. We're trying to teach general concepts here.
Voltage...the Oomph factor
You have one of three types of PV's
1) Fixed voltage. They are "regulated" to a speific set voltage. They may dwindle below it before cutting out, but they are still "fixed" in that you can't adjust them. They are regulated though....electronic circuits inside attempt to make the voltage the same regardless of the battery charge. Some only do this when the battery is above the set voltage limit.
2) Variable voltage. Adjustable voltage (also adjustable wattage) e-cigs have circuitry to bump-up (boost) or regulate down (buck) battery voltage according to a dial that you set. Variable Wattage (VW) e-cigs read the resistance of the coil you've screwed onto the connector and calculate the voltage you need to acheive a desired wattage setting. So they adjust the voltage for you.
3) Follows battery voltage - ie two wires, a battery, and a connector. Vaping directly off the battery at whatever voltage it has at the moment. Typical for all-mechanical mods. Li-Ion (and that class of batteries including IMR) have a top voltage of about 4.2 volts but they drop quickly to about 3.7/3.6 volts and stay in that rage for most of the usable charge and then drop quickly below that to cut-off voltage.
Each of these types come in either swappable battery configurations (where you have a "cell" that you can remove) or internal battery configurations where you charge the whole unit somehow and cannot remove the battery from the electronics/mechanics.
How do you make a fixed voltage e-cig hotter or cooler? By selecting the proper ohm coil. It's the only "variable" that you can change. The voltage is fixed. And as we've learned above, if any two factors are known, all factors are set. So the heat will be P = V2 ÷ R (or Watts = Voltage squared divided by coil ohms) for a single coil. So if you want to vape at 8 watts, and you know the voltage of your fix-volt e-cig...use R = V2 ÷ P (voltage squared divided 8). A 3.7 volt e-cig needs 3.7 x 3.7 / 8 = 1.71125 ohms to get 8 watts. Of course, there's wiggle room. And in fact coil ohms vary a bit due to manufacturing variability. 2.0 ohms will work. 3.0 ohms is not that good. 1.5 ohms may even be a bit hot. On the other hand, some e-cigs are 3.4 volts (like the original authentic eGo) and they may do better at 1.5 ohms.
How do you make a VV, or VW e-cig hotter or cooler....by adjust the dial, of course! The difference is that with VW, it will "sense" the ohms of the coil that you have screwed on and calculate the proper voltage...assuming you don't fake it out with the dual-coil thing. More on DC (dual coil) stuff later. Due to differences in devices and coils, you may have to adjust VW a bit anyway. But it gets you into the ballpark regardless of what ohm coil you screw on.
So for regulated fixed voltage stuff, or for follow-battery-voltage stuff, you must select the proper ohms ahead of time...there's no adjustment for the voltage/wattage on the e-cig. Get it wrong, and it's too hot or too cool. It's not super picky though...there's a workable range of ohms within reason.
Wattage
You know wattage. It's like incandescent light-bulbs. More wattage = more energy used = hotter/brighter. It's the result of the voltage and the coil ohms per the formula above. Watts = heat for our purposes. Normal ranges are about 7-9 watts per coil. This is for "normal" coils. There are dual coils ...where the PV must supply double the current (amps) in order to keep the voltage high enough for two coils. Think of it like a two lane toll booth on a toll road allowing double the cars through at once. Electrons per second past a point = amps (current). So more amps are required for dual coils at any given voltage.
The watts for dual coils are, not surprisingly, doubled for the device as a whole. If each coil is 8 watts, you need to supply a dual coil with 16 watts total. This is why dual-coil users often run up against amp limits on their devices. The device exceeds it's expected amp draw and either signals a "short" or drops the voltage to compensate for lack of amps. It won't work as expected, if at all, unless your PV can supply the amps at whatever voltage you set.
For VW devices...just set the wattage. For VV only devices...calculate the voltage or just start low and adjust higher as needed. To calculate the voltage:
So for single coils: Try 7-9 watts as a ballpark/average. Let's say 8. So voltage = Square-Root of (P X R) = Square-Root of (8 X ohms)
For dual coils: double the ohms 1st. A 1.5 ohm dual coil is really two 3.0 ohm coils side-by-side on the same connector. So the voltage is calculated for 3.0 ohms, NOT the 1.5 ohms. So around 5 volts should be good for a 1.5 ohm DC at 8 watts per coil. Because the square root of 24 (3 ohms times 8 watts) is about 5 (OK....4.898979485566356
)Milliamp Hours (mAh)
You get billed on your electric bill by Kilowatt hours. That's the # of (thousands of) watts used for an hour. Note that there's an amount and a duration. A 2000 watt heater run for exactly one hour is 2 KWh. In the USA that's about 22 cents worth of energy, depending on location. So what is a Milliamp hour? Well, a milli-amp is 1000th of an amp. Thus 1/1000th of an amp run for 1 hour. An e-cig battery rated at 650 mAh can run 650/1000ths of an amp for an hour (well, not exactly, but electronics are usually using very small loads so that's how they are rated...in mAh).
However, that heater is dang cheap when you consider how hard it is to stuff that much energy into an e-cig battery. That would be a 1,000,000 mAh battery. See? lol. It's hard to stuff electrons into a battery. And we never have enough capacity.
So mAh is a capacity measurement. Like the size of a gas tank. Or the amount of water in a full water tower. I suppose you could give them a # of electrons difference between poles rating, but it's a crazy big number. Just remember that mAh is a capacity estimate....it gives you a rough idea of how much energy is stored in the battery for use over time.
Just like you can't predict how far an arbitrary car will drive by knowing the size of the tank alone (you'd also need to know the engine's MPG and the weight, and the amount of idling...etc) you can't predict how long a battery can be used without knowing the "load" on the battery. There is a common "rough guess" figure floating around here that every 100 mAh of battery capacity = approximately 1 hour of average vaping time. Even that varies quite a bit, because device designs, coils, and personal vaping usage vary quite a bit. And so do the mAh rating accuracies of the batteries. Some manufacturers seem to be more...accurate...than others. Ahem.
However, it still gives you a rough idea of the capacity of a battery when compared to another similar device used with the same coil by the same person.
Note that the safer chemistry of the IMR batteries has a trade-off in slightly lower storage capacity as compared to Li-Ion. However there are "hybrids" that use other chemistry that's somewhere in between. And ...it's an art and a science...even designing these things. There are new developments on the horizon all the time. So keep up to date and double check current information as this post becomes more out of date.
amp limits
SLR
Symbols on multimeters
What about:
mAh?
Series vs Parallel (or covered under DCC)
Battery stuff or link to Battery University.
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"A vaper without a multimeter is like a doctor without a stethoscope."
-Switched
Buy a multimeter. Any digital multimeter will do, you don't need a Fluke! You can get a good one for $15-25 from Sears, Lowe's or on the Amazon. You need your multimeter to check the resistance of your atomizers and/or voltage of your battery.
Connect the black test lead to the jack marked "Common" or "-"; connect the red test lead to the jack marked with the Ω (Ohm symbol) or letter "R" near it.
To check the resistance of your atomizers:
1. Turn your multimeter on and select the lowest Ohms setting, usually 200Ω.
2. Look at the display; the left side of the screen should display number 1.
3. First, test the resistance of your leads. Touch to two leads together, firmly, and wait for numbers to stabilize. On the right side of the screen, you should see a number between 0.0 and 0.4, or so. This is the resistance of your leads. Remember that number.
4. Now, to test your atty. Position your carto firmly on your desk; you don't want it to slip and slide all over the place. Touch one lead to the hole in the center of the atty and the other lead to the threads. Again read the display after the numbers have stabilized.
5. Subtract the resistance of your leads (#3) from the resistance of your atty(#4). This is the resistance of your atomizer.
This process takes some getting used to. Steady hand helps. Just keep practicing and you'll figure it out.
There are many tutorials on Youtube--watch them if you're a visual learner:
I like this one by GeekGirlVaper:
If you only want to check the resistance of your atomizers, you may want to consider buying this Atomizer and Cartomizer Ohm Meter--a very nifty, albeit single use, device:
It can be used with all native 510 and 901/808 connectors; extensions or adapters are needed to test other atomizers (including eGo-threaded heads, which require a 510>eGo adapter). Many vendors carry them, including Smoktech, MadVapes, IndyVaporShop and others.
If you own an APV that checks the resistance of your atomizers, like Vamo, Zmax, eVic or ProVari, you don't need to buy a multimeter.
-Switched
Buy a multimeter. Any digital multimeter will do, you don't need a Fluke! You can get a good one for $15-25 from Sears, Lowe's or on the Amazon. You need your multimeter to check the resistance of your atomizers and/or voltage of your battery.
Connect the black test lead to the jack marked "Common" or "-"; connect the red test lead to the jack marked with the Ω (Ohm symbol) or letter "R" near it.
To check the resistance of your atomizers:
1. Turn your multimeter on and select the lowest Ohms setting, usually 200Ω.
2. Look at the display; the left side of the screen should display number 1.
3. First, test the resistance of your leads. Touch to two leads together, firmly, and wait for numbers to stabilize. On the right side of the screen, you should see a number between 0.0 and 0.4, or so. This is the resistance of your leads. Remember that number.
4. Now, to test your atty. Position your carto firmly on your desk; you don't want it to slip and slide all over the place. Touch one lead to the hole in the center of the atty and the other lead to the threads. Again read the display after the numbers have stabilized.
5. Subtract the resistance of your leads (#3) from the resistance of your atty(#4). This is the resistance of your atomizer.
This process takes some getting used to. Steady hand helps. Just keep practicing and you'll figure it out.
There are many tutorials on Youtube--watch them if you're a visual learner:
I like this one by GeekGirlVaper:
If you only want to check the resistance of your atomizers, you may want to consider buying this Atomizer and Cartomizer Ohm Meter--a very nifty, albeit single use, device:
It can be used with all native 510 and 901/808 connectors; extensions or adapters are needed to test other atomizers (including eGo-threaded heads, which require a 510>eGo adapter). Many vendors carry them, including Smoktech, MadVapes, IndyVaporShop and others.
If you own an APV that checks the resistance of your atomizers, like Vamo, Zmax, eVic or ProVari, you don't need to buy a multimeter.
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Disclaimer: This is the most simplistic explanation and is addressed to new vapers mostly or vapers who are happy within the recommended "just right" power zone (4.5-8.5 watts). If you are using dual coil atomizers or are interested in high wattage vaping, please see post #(ref needed) and #(ref needed). You will also have to understand the concept of amp limits and how it applies to high power vaping.
Ohm's Law as it pertains to vaping is really not that complicated--and it's very useful when you want to know what you're doing.
Voltage and wattage are often misunderstood by new vapers. Wattage is the power (heat, sweet spot) that your PV (battery and atomizer) generates. Wattage = Voltage (of your battery) squared divided by Resistance (Ω) of your atomizer [P=V[SUP]2[/SUP]/R]. If you're not good at math, don't worry, use this easy calculator:
Online Conversion - Ohm's Law Calculator
Of course, if you own a VW (variable wattage) device, you don't really need this calculator because your device will do the math for you.
The wattage you want, especially at the beginning of your vaping career, should be somewhere between 4.5 and 8.5 Watts. Anything lower than 4.5 watts may not vaporize your juice properly and will not produce enough warmth and vapor. Anything above 8.5 watts increases the risk of burning the filler in your cartomizers (if you're using them) and even some juices, especially the delicate ones.
There are, of course, other variables, like eliquid and JDD (juice delivery devices) that you're using on your batteries. Seven watts on a filler type cartomizer may feel different than the same 7 watts on a fillerless clearomizer or a dripping atomizer. The same is true for different eliquids; tobaccos, chocolate and coffees generally require more wattage (heat), while fruit and other delicate flavors do better with less heat. Everyone's sweet spot is different--those are just very general guidelines.
If you want to know more, this is a good read:
http://www.e-cigarette-forum.com/fo...-stuff-i-double-dog-dare-you.html#post9112897
Experiment and you'll find your own bliss in no time!
The chart below is a good guide to safe vaping, even though some think it's a bit conservative. The newer chart, created by TomCatt, can be viewed in post #(ref needed).
Ohm's Law as it pertains to vaping is really not that complicated--and it's very useful when you want to know what you're doing.
Voltage and wattage are often misunderstood by new vapers. Wattage is the power (heat, sweet spot) that your PV (battery and atomizer) generates. Wattage = Voltage (of your battery) squared divided by Resistance (Ω) of your atomizer [P=V[SUP]2[/SUP]/R]. If you're not good at math, don't worry, use this easy calculator:
Online Conversion - Ohm's Law Calculator
Of course, if you own a VW (variable wattage) device, you don't really need this calculator because your device will do the math for you.
The wattage you want, especially at the beginning of your vaping career, should be somewhere between 4.5 and 8.5 Watts. Anything lower than 4.5 watts may not vaporize your juice properly and will not produce enough warmth and vapor. Anything above 8.5 watts increases the risk of burning the filler in your cartomizers (if you're using them) and even some juices, especially the delicate ones.
There are, of course, other variables, like eliquid and JDD (juice delivery devices) that you're using on your batteries. Seven watts on a filler type cartomizer may feel different than the same 7 watts on a fillerless clearomizer or a dripping atomizer. The same is true for different eliquids; tobaccos, chocolate and coffees generally require more wattage (heat), while fruit and other delicate flavors do better with less heat. Everyone's sweet spot is different--those are just very general guidelines.
If you want to know more, this is a good read:
http://www.e-cigarette-forum.com/fo...-stuff-i-double-dog-dare-you.html#post9112897
Experiment and you'll find your own bliss in no time!
The chart below is a good guide to safe vaping, even though some think it's a bit conservative. The newer chart, created by TomCatt, can be viewed in post #(ref needed).
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