What Are Ohms?
The Venn diagram overlap of "choosing vaping coils" and "meditation mantras" is quite small: it's all about the ohmmmm. Regardless of whether you've been vaping for a while or a complete newcomer, you've probably have heard the term "ohm" being thrown around. Vape coils have different ohm levels, and it’s important to know what that means and how it affects your vaping experience.
Basically, an ohm is a unit of measurement specifying how much resistance your coil has to electricity. The more resistance your coil has, the less electricity will flow through the atomizer when the same amount of power in volts is applied to the wire. The less your coil resists electricity, the more power flows through it, creating heat and, due to that heat, vapor. You can check the resistance of your coil on the product’s packaging or on the coil itself next to the Ω symbol.
There are advantages and disadvantages to using higher or lower resistance coils. In this article we’ll look at how your experience changes depending on your ohm resistance.
Lower-resistance coils are usually of the "sub-ohm" variety, so named because the total resistance of the wires in all coil wraps is below 1.0 ohm. If you're using a device with less resistance, there’s more electricity flowing through from the atomizer than when you apply the same amount of power to a higher resistance coil, creating an overall warmer, denser vape. The most important advantage, and the reason why vapers choose coils with a sub-ohm resistance, is that the greater power produced by low resistance creates bigger clouds than cooler, higher resistance coils. This can really enliven your experience of vaping!
The downside to low-resistance coils is that they demand a lot of power. This is why box mods generally only work with high-discharge batteries capable of delivering 20 amps of power or more. That high power, while delivering big clouds and dense, satisfying flavor, also means you'll vape through your liquid much faster than with a low-powered device.
As you might expect, many things are reversed with high-resistance coils. Because less electricity flows through them, more energy is retained in the form of heat. This means that less power is required to produce vapor, but the coils won't be able to handle nearly as much power as those in the sub-ohm category. These can be considered negatives if you’re looking for stronger flavor and bigger clouds, but high-resistance vapes also have their advantages.
First, the lower power demand means your device can be smaller - think cigalikes and pod mods. Further, since you're not generating a ton of power, your vapor will generally be cooler and produced at a lower volume. Not only does that mean you'll be consuming much less e-liquid, in a public setting where you're not trying to advertise your "sick clouds, bro!" that might even be an advantage.
To put ohms into context, Ohm’s Law is the scientific explanation of how ohms interact with electricity input (in volts) and output (in watts). If you’ve got a background in hard sciences or have a general knowledge of electrical engineering, than you’re probably familiar with Ohm’s Law, but if not here’s a (very) brief explainer.
The Ohm's Law equation basically reads: Current (measured in amperes) = Voltage / Resistance (measured in ohms), Power (measured in watts) = Voltage x Current. This will determine the general output of power in your vape. Named after German physicist Georg Ohm in 1827, it’s some of the cool science behind vaping.
Let's put this into practice with an example. Suppose you've got a coil with a resistance of 0.2 ohm, and a fresh battery in an unregulated mechanical mod producing 4.2 volts of power. How much power are you actually producing, and is it safe?
4.2 volts divided by 0.2 ohm resistance = 21 amp current
21 amps multiplied by 4.2 volts power = 88.2 watts
Okay, 88.2 watts is a lot! That'll be plenty of power to fog up a room. But, keeping in mind that even most high-discharge lithium ion batteries can only produce 20 amps of continuous draw, you're risking battery venting or explosion by pushing them too hard. For this application you'll need a multiple-battery mod - have you noticed that most single-18650 mods only go up to 75-80 watts of power output? Now you know why.