Every e-cigarette/atomizer combination provides power through a function of amps, ohms, volts and watts.
Although these terms can be confusing, to vape safely you need to have a basic understanding of how each function works. That way you can replace each part of your set up and safely enjoy a vape. In this article we’ll discuss how different ohm loads, paired with different amounts of volts or watts effect the amperage.
We’ll also discuss the difference between voltage and wattage as a power gauge.
Here are the mechanics of what is happening in a common e-cigarette set-up:
- They fire at a regulated 3.7 volts.
- Generally their atomizer is a preinstalled coil of around 1.5 ohms.
- This creates about 2.4 amps
- Once we know the amperage we can determine that the wattage will be around 9 watts
So what the hell does that mean?
To put it simply electrical currents are a lot like water currents and rivers.
3.7 volts is the amount of power coming from the battery. This is the volume of electricity. Compared to most power sources, 3.7 volts is like a puddle
- -In mechanical mods (without a kick device) the firing voltage will depend on the overall charge left in the battery. (4.2 volts at full charge and decreases to 3.4 volts when the battery is out of charge)
- -In a regulated device (variable voltage) you can decide what voltage you’d like to fire at. This also reduces the amount of time your battery will last.
1.5 ohms is the resistance to the current, or flow of power. Resistance is like large rocks creating drag on the flow of the river, slowing it down. Higher ohms is more resistance, and lower ohms is less.
- Replaceable coils/cartomizers/atomizers are labeled and sold at a specific ohm load.
- Rebuildable coils must always be checked with an ohm reader, or a device with an ohm read feature (such as the MVPv2, Vamo, VTR etc.)
2.4 amps is the draw of power from the battery. This is the overall speed of the current. Batteries are rated on the amount of amperage they can produce.
- Regulated devices have their own amperage limit, so putting a 30 amp battery in a 5 amp Vamo won’t increase the amperage limit.
9 watts is the total amount of power. It takes into consideration the amperage and the voltage.
Low Ohms -> 3.7 volts -> High watts -> High amps
1.5 ohms/3.7 volts = 2.4 amps
To find out the wattage of the set up:
W(Wattage)=V * A
3.7 volts * 2.4 amps = 9 watts
Hooray! Middle school math!
Increase the ohms, without increasing the voltage and the watts and amps will go down.
A regulated device generally has its own amperage limit, so if you try to fire a coil with too low of an ohm load at too high of a voltage your device won’t fire. However, mechanical mods do not have this safety feature. So, you should use a vaping calculator make sure your battery is able to handle the amperage. Check out our vape battery safety guide for even more information.
Examples of batteries
- An Itaste MVP v2 has a 4 amp limit, so I can take it to itâs highest voltage (5 volts) and have no problems with a coil above 1.2 ohms.
- The Sony VTC4 18650 battery has a 30 amp limit, so I can vape it at its full charge (4.2 volts) and have no worries with a coil above 0.14 ohms
We also have some really cool Vaping Power chart Cheat Sheets you can print out. They show you the power output when you know the battery voltage and atomizer resistance (Ohm).
Related Safety Guides
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