You can measure the voltage drop (inefficiency) of an unregulated device by putting a resistance/volt meter across the positive and negative posts of a atomizer, loaded with a coil as it needs to be measured under load. Measure the voltage and subtract it from the voltage that was in the battery. The difference is the voltage drop.
The voltage drop just within an unregulated device will increase exponentially the lower the coil resistance. The point is that any measurement of a device is only relevant for comparison if you use exactly the same coil. Also this method does not take into account the battery's internal resistance or voltage drop. So unless you are able to measure this value independently what you will get is the sum voltage drop of that device, at that resistance, with that particular battery. The voltage drop of a give model of battery can vary even direct from the factory. The capacity and voltage drop of a battery will decrease over time and with use.
So if you used the same battery and atomizer on another device you would have a value to use for direct comparison.
eg.
Stingray X clone loaded with dual coils at 0.25 ohms, using a new(ish) Samsung 30Q
Battery voltage 4.2 volts
Measured voltage 3.68 volts
Voltage drop 0.52 volts
Using Ohms law this setup produces a theoretical 70 watts, what you actually get at the coil is 54 watts.
This equates to a 77% efficiency. Using a lower resistance coil would produce a higher wattage, but your voltage drop and therefore efficiency will decrease exponentially.
The voltage drop just within an unregulated device will increase exponentially the lower the coil resistance. The point is that any measurement of a device is only relevant for comparison if you use exactly the same coil. Also this method does not take into account the battery's internal resistance or voltage drop. So unless you are able to measure this value independently what you will get is the sum voltage drop of that device, at that resistance, with that particular battery. The voltage drop of a give model of battery can vary even direct from the factory. The capacity and voltage drop of a battery will decrease over time and with use.
So if you used the same battery and atomizer on another device you would have a value to use for direct comparison.
eg.
Stingray X clone loaded with dual coils at 0.25 ohms, using a new(ish) Samsung 30Q
Battery voltage 4.2 volts
Measured voltage 3.68 volts
Voltage drop 0.52 volts
Using Ohms law this setup produces a theoretical 70 watts, what you actually get at the coil is 54 watts.
This equates to a 77% efficiency. Using a lower resistance coil would produce a higher wattage, but your voltage drop and therefore efficiency will decrease exponentially.
