Voltage and current?

[mattrix]

Yes, some ohms law questions, sort of. About variable watt mods.

A mod will only achieve its maximum rated output over a range of resistance.
A resistance lower than this range will draw the mods maximum current and somewhat less resistance will be considered a short, and the mod wont fire.
A resistance higher than the range will be driven by the mods maximum voltage.

Why does a mod specify an upper resistance? After all we don't need open circuit protection and I presume the mod will still fire with R greater than that specified.

For the same watts, is there any difference in the vape experience between a coil driven by the maximum voltage (at lower current -high R) compared to the one drawing maximum current (at lower voltage -low R)? Assume the 2 coils are the same in all respects except for the material they are made of.

 

[IMFire3605]

While true the higher resistance coil will ask less amps than the lower resistance coil, most current mods have a maximum voltage DC to DC converter, hit maximum voltage your watts are also maxed. 2 battery series battery configuration for example, 2 X Batteries is Voltage X 2, and batteries operate in a voltage range of 3 to 3.2v per battery lowest to 4.2v Fresh Charge, that gives us a maximum voltage range of 6.0v to 8.4v, unless the mod control board has a voltage booster circuit you can't go beyond those voltages. So even if the mod is set to 200watts but with a very high ohm coil at 8.4v maxed out you are only getting maybe 150watts, there are limitations. With a booster circuit you might surpass that limit, but then you start taking raw amps and converting them into raw volts to achieve it so you really do not have a real benefit to do so, most single battery mods you'll see a booster circuit with a bucking circuit, most multi-battery mods just have a bucking circuit which shunts excess voltage supply elsewhere away from the coils, works opposite to what a booster does. However each mod has an optimal Ohm range to reach max watts it is designed for, the older Sigelei 150watt mods as example here, optimal range for them at max settings was between 0.2 to 0.3ohm to reach 150watts, but a 0.5ohm coil you are maxing out at around 110 to 130watts.

Check out steam-engine.org, has many vaping programs on the site, including an Ohms Law calculator, play around with it and you will see how all 4 variables work in tandem, volts, current (amps), resistance (ohms), and power (watts), changing just one though you only need 2 variables changes all 4.

Myself I vape most the time at about 8 to 10 watts on a 1.2ohm to 1.8ohm single coil mouth to lung, changing up with a dripper or sub-ohm tank with a dual coil in the 0.4 to 0.6ohm range at around 30 to 40watts, and rarely anymore do I go crazy with a 0.2ohm in the 80watts range. My experience the most enjoyable is my MTL setup, but I get better flavor out of my mid range drippers/sub-ohm tanks due to surface area and less airflow compared to my super-sub-ohm high wattage setups which need massive airflow, that extra air dilutes the flavor down. I also get better battery efficiency with the higher ohm the coil is due to less raw amps pulled that doesn't drain the battery as fast, though I am what is termed a flavor chaser more than I am a cloud chaser, it is just a matter of experimenting and finding you nirvana plateau.