For disposable e-cigarettes or some of the simpler setups it’s not necessary to learn how the e-cig circuit works, simply because there’s no ability to change what’s going on. If, however, you’re looking to explore the intricacies of more flexible vapes, this guide will give you the knowledge to go confidently on your way! We’re going to cover the basic physics of electrical circuitry, including volts, watts, and amps, and their intimate relationship. Then, we’ll go over Joule’s First Law, which tells us how much energy is turned into heat!
Volts, (Ohms,) Watts, and Amps
You’ve probably heard of voltage in reference to batteries. Voltage is the difference in electrical potential energy between two points. In the case of a battery, those are the positive and negative sides. When a connection is made, the higher the voltage, the more pressure there is on the electrons to follow the circuit. Voltage is measured in volts, such as the 3.7 volt standard batteries.
Even the most highly conductive substances, such as gold or copper, offer some resistance to the flow of electrons. This resistance is measured in ohms, and commonly seen values for atomizer setups are between 1.1 and 3.0 ohms or so. Higher and lower values are seen, but as you’ll see, it can really change what happens. Keep in mind that the coil in an atomizer is not the only thing contributing to the resistance, so measure it when the atomizer is fully assembled!
The amount of electricity going through the circuit is known as the current, and is measured in amps. Ohm’s Law states that the current in a circuit is equal to the voltage divided by the resistance. For example, if we had a standard 3.7 volt battery and an atomizer assembly with a resistance of 1.1 ohms, there would be a current of 3.7 volts / 1.1 ohms = ~3.36 amps!
The wattage is a measurement of the power put into a system. It’s commonly seen as an adjustable option on many batteries, and is equal to the voltage times the current (3.7 volts * 3.36 amps = 12.43 watts). Equivalently, it’s equal to the voltage squared divided by the resistance, and this is how adjustable wattage devices actually work! They measure the resistance, and output a voltage corresponding to the desired wattage. For this reason, there’s not that much actual difference between VV and VW batteries besides personal preference.
Joule’s First Law: Resistive Heating
A much better measurement than wattage for the output of your setup can be found with Joule’s First Law. This law states that the amount of heat released by an electrical circuit is proportional to the current squared times the resistance. While not directly usable by us (for now), this let’s us get a rough idea of how to pump up or tone down our vaporizer! A low resistance build, such as a sub-ohm setup, must have an extremely high current to get so much power. While that’s wonderful for vapor production, it can be extremely dangerous. Increasing the voltage can be a more effective way of getting more out of your vape, while not straying into too dangerous territory. Be sure your mod has good safety features, however!
Check in next time when we look further into the mechanics of vaporization!