This article was originally written in January 2016. It was imported to the new blog in 2018
Quick post to clear some misconceptions.
As we have seen from the previous article “Regulated Mods“, the Input Side is completely unaffected by the resistance of the coil. This basically means that if the power setting remains unchanged, battery life will not be affected by the coil resistance. This is because the power signal is converted in the Output Side to match the resistance of the coil. The Input side remains unchanged.
We will use the same example as the previous article to demonstrate this: A DNA40 configured for 20W. The example is a bit redundant, but simply shows that no matter what coil is installed on the mod, the power input remains the same.
From our previous article, we concluded that at 20W the DNA40 will actually need to pull 21.28W from the battery, with a current draw between 5.07A and 6.86A depending on the voltage coming from the battery.
The controller has grabbed 21.28W from the battery, and now wants to send 20W to the coil.
If our device has a 0.2 Ohm coil,the controller will send:
Current = √ (20/0.2) = 10A
Voltage = √ (20*0.2) = 4V
If our device has a 1 Ohm coil,the controller will send:
Current = √ (20/1) = 4.47A
Voltage = √ (20*1) = 4.47V
If our device has a 2 Ohm coil,the controller will send:
Current = √ (20/2) = 3.16A
Voltage = √ (20*2) = 6.3V
If our device has a 3 Ohm coil,the controller will send:
Current = √ (20/3) = 2.58A
Voltage = √ (20*3) = 7.74V
As you can see, coil resistance played no role on the input side. Only the output side was adjusted to provide the power to the coil.