Volts verses Amps: Understand the Difference Before You Buy
Spend some time browsing our site and you will see that we have plenty of options for 12v and 24v battery chargers, battery maintainers, and jump starters. Units built for 12v are adequate for most professional needs. But every now and again, you might run into a 24v system. With both 12v and 24v products, there is also the question of amperage.
If you do not have a firm grasp on the difference between volts and amps, a little bit of education is in order before you buy your next piece of Clore Automotive equipment. You might never need a 24v jump starter, for example, but a 12v unit will not get the job done if you ever run across a stranded vehicle with a 24v system – regardless of the number of amps it puts out.
Different Ways to Measure Electricity
Electricity doesn’t have mass in the same sense that a load of bricks does. Therefore, we cannot measure it by putting it on a scale. We need a different means of measurement. Because electricity has little value when it’s not doing any work, the best way to measure it is to do so when it is working. And for that, we have four options.
Measuring voltage and amperage are two of the options. The other two are wattage and resistance. We will not get into wattage and resistance in this piece, as they don’t apply to things like battery maintainers and jump starters.
Voltage is a Measurement of Pressure
Voltage is a measurement of the electric potential of a current as it flows through a circuit. It has been described as the speed at which individual electrons move. However, a better description is one of pressure. Imagine water pressure in a hose or pipe. Water under pressure has potential energy stored in it, energy waiting to be released by opening a valve. Voltage is the equivalent in the electricity realm.
A 24v current has twice the energy potential as a 12v current. Tap into that potential to do the same amount of work and you’ll notice that the 24v system offers more raw power. More pressure equals more work.
Amperage is a Measurement of Flow Rate
Measuring amps is another way to measure electricity under load. Amperage is a measurement of flow rate, similar to measuring the rate of water as it flows out of a valve. Incidentally, this is why some experts frown on the idea of describing voltage as the speed at which electrons move. It is too similar to the idea of amperage being a measurement of flow rate.
Amperage becomes important in our industry because you need performance over time. Think about jump-starting an SUV or minivan. You may have to crank the engine for several seconds to get it to start. More amps mean a more consistent flow of power over a longer period of time. Fewer amps mean just the opposite.
A Practical Application
With an understanding of the differences between voltage and amperage, let us close with a practical example. Let’s say you are called out to a job involving a heavy-duty pickup truck needing a jump start. You only have a 12v jump starter while the truck has a 24v system. Your unit will not produce enough power to turn the engine over, even at 700 cranking amps.
Looking at two 12v batteries connected in series presents the same problem. A 12v jump starter will not be enough. That is why we recommend equipment that can operate in both 12v and 24v mode. That way, you will be able to deal with any automotive electrical system.
