Confused about temp control

[wizardofozone]

All of my clearos really heat up the Pyrex glass at about 70 watts, including a Herakles Plus when any are on one of Herackles regular coils.

If however I screw on a Herakles Plus with one of their temp control nickel coils the glass stays much much cooler even set at 70 watts on both 100 watt Esticks

TC is expected of the 200 Snow Wolf, and my 200 Reuleux to stay cool as these are TC controlled.

But only the small 40 watt istick advertises that the unit has 'temp control circuitry' ... (I have the older 100 watt Isticks, I'm aware the new Istick 100 watter does now have TC.)

I wrongly thought temp control was a function of a nickel coil not internal unit circuitry.... and to boot, both my 100 watt Isticks are cool as a cucumber with the Herackles nickel coil .... and my wattage set at the same 70 watts.... although the Istick wont show the degree temp as the Snow wolf and
Reuleaux does.

The 100 watters have no temp control but both are noticably cooler with the nickel coil .... So will any sub ohm unit run cooler just because of a nickel coil being attached despite the lack of internal temp circuitry ?

 

[DaveP]

Temp control is a function of the electronics as well as the wire type. TC control has to be used with a wire that has a recognizable rise and fall in resistance with temperature so that the circuitry can return a valid temp while you are vaping in TC mode.

Some wire types can be used in wattage/voltage mode and TC mode, but the mod has to support TC to work with the correct coil type and you have to tell it whether you have stainless steel, nichrome, or titanium so that it can perform the calculations to read the coil's temperature correctly using the TCR (temperature coefficient of resistance ) constant for a particular wire. The TCR is programmed into the mod and can be changed by the user.

 

[Randy C]

When a TC mod has been set to a certain watts, does TC increase/ decrease the watts to achieve the desired temp? I guess what I'm asking- does TC over-ride what the watts have been set at? If not, how does a TC mod regulate temperature?

 

[DaveP]

When a TC mod has been set to a certain watts, does TC increase/ decrease the watts to achieve the desired temp? I guess what I'm asking- does TC over-ride what the watts have been set at? If not, how does a TC mod regulate temperature?

You don't set watts in TC mode. You pick TC mode, choose the type of wire (Nichrome, Titanium, and Stainless Steel) you are using in the menu, set a temperature that you like and the mod maintains the temperature you set.

What does change is voltage to the coil. Watts is a calculation done by a formula. I like Volts^2 / Resistance. It's easy to do in your head. 4V squared divided by 2 ohms = 16/2=8 watts.

Ohms Law Wheel

The TCR constant is based on the wire you use. TCR makes sure that the calculations are correct as long as you pick the right wire in setup. It's different for Nichrome, Titanium, and Stainless Steel.

Kanthal isn't compatible with TC because it has a non-linear change in resistance with temperature.

 

[groomt]

I don't use TC, but they absolutely allow you to set watts in temp mode. How this effects it I don't know.

 

[Train2]

My understanding is that, yes you do set watts, and that the Temp is a MAXIMUM.
So it's estimating temp (by calculating known change in resistance of the particular metal of your coil at different temps) and then will OVER-RIDE the watt setting - lowering it - if your coil hits that max temp.

 

[Spirometry]

I wrongly thought temp control was a function of a nickel coil not internal unit circuitry.... and to boot, both my 100 watt Isticks are cool as a cucumber with the Herackles nickel coil .... and my wattage set at the same 70 watts.... although the Istick wont show the degree temp as the Snow wolf and
Reuleaux does.

The 100 watters have no temp control but both are noticably cooler with the nickel coil .... So will any sub ohm unit run cooler just because of a nickel coil being attached despite the lack of internal temp circuitry ?

The mod has to be capable of dynamically applying more voltage as the resistance increases.

If you took a 0.15 ni coil and set it at 70 watts, then the mod will apply 2.7 volts. The resistance of the nickle coil will increase when it gets hot. Say it jumps up to 0.30, if the mod can't read the change on the fly and change the voltage on the fly, you're only going to get 35w even though you have it set at 70w

 

[groomt]

So if you are new to TC, how do you know the parameters to set your mod to? Is there a temp control for dummies somewhere? Do you start at the base recommended by the manufacturer and go up from there?