TC beyond Ni200: Nickel Purity, Dicodes; Ti, SS, Resistherm NiFe30; Coefficient of Resistance

[GeorgeS]

However many watts to bring some amount of surface area to a set point of temperature is what its all about for me.

Given the same wire type, gauge and ID of coil, more wraps equates to more wire mass, surface area and higher ohms.

In general smaller diameter wire heats/cools faster, has higher resistance and requires less power than larger diameter wire does.

Then there's the "balancing act" between the coil mass vs wick mass. As evidenced by my failed experiments with 28-32AWG wire and 3-4.5mm ID coils: larger diameter wire is better suited for larger ID coils with lots of wick then small diameter wire. Small ID coils with not much wick are better suited for smaller diameter wire.

Since we're talking TC here I try to get as high of a resistance with many wraps as I can fit.

 

[cigatron]

Its current draw that matters

20w at 1ohm is about 4.5 amps at 0.5ohm its about 6.5

True, but that .5 ohm coil only needs 3.16 volts to produce that 20w while the 1 ohm coil needs 4.47 volts to produce the same wattage. That increase in voltage potential does not come without a price. Both coils will deplete the battery at approx the same rate because Wattage = Volts x Amps.

Run a couple of test builds on a tc mod at 1 ohm and .5 ohm and run them at the same wattage. I think you'll find that you can vape approx the same ml of juice with either before completely depleting your battery.

 

[JimScotty0]

However many watts to bring some amount of surface area to a set point of temperature is what its all about for me.

Given the same wire type, gauge and ID of coil, more wraps equates to more wire mass, surface area and higher ohms.

In general smaller diameter wire heats/cools faster, has higher resistance and requires less power than larger diameter wire does.

Then there's the "balancing act" between the coil mass vs wick mass. As evidenced by my failed experiments with 28-32AWG wire and 3-4.5mm ID coils: larger diameter wire is better suited for larger ID coils with lots of wick then small diameter wire. Small ID coils with not much wick are better suited for smaller diameter wire.

Since we're talking TC here I try to get as high of a resistance with many wraps as I can fit.

There is a great blog here by @State O' Flux that discusses Heat Flux which is I think where this discussion is going.

Steam Engine: Basic & advanced features: Pts. One & Two | E-Cigarette Forum

Scroll down to the discussion on Heat Flux where it is thoroughly discussed.

 

[GeorgeS]

Run a couple of test builds on a tc mod at 1 ohm and .5 ohm and run them at the same wattage. I think you'll find that you can vape approx the same ml of juice with either before completely depleting your battery.

Actually, when it comes to TC it won't matter what the wattage is used right?

Here we need to define our assumptions.

Assuming that we are using the same AWG and type of wire I'd claim that the 1ohm coil has 2x the mass and 2x the surface area than the 0.5ohm coil does. While the extra surface area would eventually afford more vapor production (and use more juice) I think it would come at a high cost of power because the extra mass would take longer to heat up.

However if we assume that the higher ohm coil is made from a smaller diameter wire that still covers the same (or more) surface area as the 1ohm coil above, it could still produce more vapor than the 0.5 ohm coil with a fraction of the mass requiring less power to reach the temperature set point and more than likely needing a lower temperature set point because of larger surface area and vapor production.

With the small diameter wire I favor 15-25W/J is all that is needed to reach a seemingly mundane 380-450F temperature set point. My two SS430 builds that are close to 2.0ohms can be driven with as little as 10-15W and the same temperature range.

 

[Quantum Mech]

Yeah I can see where your coming from Cigatron

The increase in voltage does require an increase in current draw and all would in a perfect no loss laboratory set up equal out

But the efficiency of the voltage regulators in a given device will be what decides the battery life in the real world we are using them

With a high efficiency chip that will favour the higher ohm coil

 

[GeorgeS]

There is a great blog here by @State O' Flux that discusses Heat Flux which is I think where this discussion is going.

Steam Engine: Basic & advanced features: Pts. One & Two | E-Cigarette Forum

Scroll down to the discussion on Heat Flux where it is thoroughly discussed.

Thanks! Great link.

 

[cigatron]

Actually, when it comes to TC it won't matter what the wattage is used right?

Here we need to define our assumptions.

Assuming that we are using the same AWG and type of wire I'd claim that the 1ohm coil has 2x the mass and 2x the surface area than the 0.5ohm coil does. While the extra surface area would eventually afford more vapor production (and use more juice) I think it would come at a high cost of power because the extra mass would take longer to heat up.

However if we assume that the higher ohm coil is made from a smaller diameter wire that still covers the same (or more) surface area as the 1ohm coil above, it could still produce more vapor than the 0.5 ohm coil with a fraction of the mass requiring less power to reach the temperature set point and more than likely needing a lower temperature set point because of larger surface area and vapor production.

With the small diameter wire I favor 15-25W/J is all that is needed to reach a seemingly mundane 380-450F temperature set point. My two SS430 builds that are close to 2.0ohms can be driven with as little as 10-15W and the same temperature range.

All true^^^^^. The original question was whether higher or lower ohm builds used more power, a generic question, so I skipped heat flux, mass, surface area and vapor production to keep it simple, even though all of those do affect efficiency.

 

[cigatron]

Yeah I can see where your coming from Cigatron

The increase in voltage does require an increase in current draw and all would in a perfect no loss laboratory set up equal out

But the efficiency of the voltage regulators in a given device will be what decides the battery life in the real world we are using them

With a high efficiency chip that will favour the higher ohm coil

Now this I have not heard. I've always assumed that a regulator outputting at or very near to source voltage ie not having to buck or boost voltage to supply the desired wattage would be the most efficient. No?

The higher voltage series batteries may make higher res builds more efficient than parallel configurations though, I guess.

School me bro. I'm always willing to learn.

 

[GeorgeS]

All true^^^^^. The original question was whether higher or lower ohm builds used more power, a generic question, so I skipped heat flux, mass, surface area and vapor production to keep it simple, even though all of those do affect efficiency.

Sure.

In a strict FV/VV setting the higher resistance coil would use less power (not taking into account flux, surface area and the like). However in a FW/VW setting they both would use the same amount of power.

I suppose that in a TC setting the coil with the highest HF and lowest HC will win out?

I just wanted to point out that the higher resistance coil might be operated at a lower power level and achieve the same vapor production. (and thereby save power)

 

[cigatron]

I suppose that in a TC setting the coil with the highest HF and lowest HC will win out?

I just wanted to point out that the higher resistance coil might be operated at a lower power level and achieve the same vapor production. (and thereby save power)

Agreed

In a strict FV/VV setting the higher resistance coil would use less power (not taking into account flux, surface area and the like). However in a FW/VW setting they both would use the same amount of power.

This one I'm going to have to noodle on a little later. Tired

 

[Quantum Mech]

Now this I have not heard. I've always assumed that a regulator outputting at or very near to source voltage ie not having to buck or boost voltage to supply the desired wattage would be the most efficient. No?

The higher voltage series batteries may make higher res builds more efficient than parallel configurations though, I guess.

School me bro. I'm always willing to learn.

Schooling will need someone far more technical than I at this level but I will attempt to explain more

Efficiency of the chip to provide the desired output with minimal losses, heat/energy not most efficient working range

Stand alone buck converters by design are the most efficient due to one less working leg on the mosfet (IIRC)

Which would make a pv with separate buck and boost converters more efficient when bucking with the lower ohm coil

With buck/boost converters there is power loss by inductor current flowing to ground and the higher the efficiency the lower the loss during switching

Will need to dig out course work to go any deeper as its not something I have used since

 

[GeorgeS]

Agreed
This one I'm going to have to noodle on a little later. Tired

Recall in a fixed voltage setting (we call it variable but the user simply picks a set point) the voltage remains the same. I=V/R: 5V/1ohm=5A, 5V/0.5ohm=10A.

I suppose an answer to "which uses more power, subohm coil or 2ohm coil" is:
"it depends on the build and how the build is used"

 

[cigatron]

Schooling will need someone far more technical than I at this level but I will attempt to explain more

Efficiency of the chip to provide the desired output with minimal losses, heat/energy not most efficient working range

Stand alone buck converters by design are the most efficient due to one less working leg on the mosfet (IIRC)

Which would make a pv with separate buck and boost converters more efficient when bucking with the lower ohm coil

With buck/boost converters there is power loss by inductor current flowing to ground and the higher the efficiency the lower the loss during switching

Will need to dig out course work to go any deeper as its not something I have used since

Right, ok. The ones with separate boost and buck circuitry are more efficient. Does that include both pwm and dc-dc converter types?

 

[GeorgeS]

With buck/boost converters there is power loss by inductor current flowing to ground and the higher the efficiency the lower the loss during switching

Will need to dig out course work to go any deeper as its not something I have used since

In general terms I think it is easier to 'buck' (and less losses) than to 'boost'. So assuming the same power level was used the lower ohm build might be more effecient.

 

[cigatron]

Recall in a fixed voltage setting (we call it variable but the user simply picks a set point) the voltage remains the same. I=V/R: 5V/1ohm=5A, 5V/0.5ohm=10A.

I suppose an answer to "which uses more power, subohm coil or 2ohm coil" is:
"it depends on the build and how the build is used"

Ok, you were referring to a fixed setting on a vv OR a mech mod. Threw me because vv's are not fixed, the voltage can be adjusted.

Assuming now that for FW/VW you are referring to a fixed wattage setting on a vw mod in which case yes, I agree with your previous post.

I was trying to read too much into it.

 

[Quantum Mech]

Right, ok. The ones with separate boost and buck circuitry are more efficient. Does that include both pwm and dc-dc converter types?

don't quote me on it (see what I did)

dc/dc is more efficient than pwm I believe due to initial firing causing increase in load

the dc/dc will only do it once where as the pwm a number of times, although I do concede pwm is out of my field

 

[GeorgeS]

Ok, you were referring to a fixed setting on a vv OR a mech mod. Threw me because vv's are not fixed, the voltage can be adjusted.

Well sort of. On a "VV" mod the user gets to set the FIXED voltage. The voltage will be the same if there is a 1.0 ohm load or a 5.0 ohm load. As long as the load (resistance) is high enough so that the current limit of the regulator is not met, the voltage will be the same. While most inexpensive "VV" mods will only "buck" some of the better ones could "boost" as well.

I was trying to read too much into it.

No worries, I do that all the time.

 

[cigatron]

Well sort of. On a "VV" mod the user gets to set the FIXED voltage. The voltage will be the same if there is a 1.0 ohm load or a 5.0 ohm load. As long as the load (resistance) is high enough so that the current limit of the regulator is not met, the voltage will be the same. While most inexpensive "VV" mods will only "buck" some of the better ones could "boost" as well.



No worries, I do that all the time.

Good thing I didn't know how far and how fast vaping gear would progress in three years otherwise I would have waited much longer to quit the stinkies.

I starting on V2 ecigs in 2013 and have owned just about every type of Battery/Mod marketed; FV, VV, VW, Mech and now TC. I'm such a sucker for new tech.

 

[GeorgeS]

Good thing I didn't know how far and how fast vaping gear would progress in three years otherwise I would have waited much longer to quit the stinkies.

I starting on V2 ecigs in 2013 and have owned just about every type of Battery/Mod marketed; FV, VV, VW, Mech and now TC. I'm such a sucker for new tech.

I'm a 'gear head' to, thankfully vaping is less expensive then Stereoscopic 3D gaming, photography or RVing but thankfully the other half has never 'audited' my vaping spending - I think she's just thankful I'm off the stinkies.

It will be interesting to see what comes after DNA200 and custom TCR settings in mods.

 

[cigatron]

Auto tcr detection and temp protect for kanthal. iJoy Asolo. Love mine. Not better than a dna200, just different. 200w, dual 18650, Auto tcr detection, boost/buck, heavily sprung 510, burn protect for any wire (including kanthal), Ni and Ti tc modes, non firmware upgradeable.

Not sure auto tcr detection is the wave of the future but it has appeared on a couple of newer mods.