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How Auto-detecting Power Converters Work

Mechanics of Auto-detecting Power Converters
The power cable for your laptop converts AC power to DC power.
The power cable for your laptop converts AC power to DC power.
© Guhl

So, how do auto-detecting power converters work to power your travel gadgets? In the United States, we use 110-volt AC power -- AC stands for alternating current. That means that the current reverses direction as part of a cycle. DC, or direct current power, always has the current running in the same direction.

You probably don't think about what direction your electrical current in running in very often. After all, you can't see it and as long as it's providing power for your stuff, why think about it, right? Well, not thinking about it isn't really a problem; that is, until you go to Germany for a conference after spending weeks on your presentation and you arrive at the meeting site only to find that your laptop is useless.

Power converters take whatever type of electrical current is available, AC or DC, as well as whatever voltage is available, and convert it into the type of electricity you need. You may already have some limited experience with something called a DC-to-AC power inverter in your vehicle. Most cars and trucks use 12-volt DC power supplied by the vehicle's battery. If you've ever been able to plug anything from your house -- like a laptop computer or a toaster -- into your car, then you've used a power inverter that was built to take 12-volt DC power and convert it to 110-volt AC power. Some cars and trucks come from the factory with this equipment pre-installed, while others rely on aftermarket parts to make on-the-go computing (or toasting) possible.

Unlike a car's DC-to-AC power inverter, or a country-specific travel power converter, auto-detecting power converters can transform any current or voltage into another current or voltage. A basic power converter contains a power supply and an interior circuit. The interior circuit moves the current rapidly, stabilizing it and changing it into the type of electricity required. Most people might not realize that we actually use power converters all the time, in most cases without even noticing. For instance, if you have a laptop computer, it actually runs on DC power, because that's the electrical current that batteries provide. However, if your laptop is plugged in, it's taking AC power from a wall socket. Your laptop's power cord has an in-line converter that changes the AC power from the wall socket to DC power for the laptop's use.

Auto-detecting power converters are a little different. They're "smart" converters. While the converter on your laptop only takes one form of current and converts it to another, an auto-detecting power converter can convert a variety of different power sources into useable power for your devices. If you travel frequently, an auto-detecting power converter can be a key tool to keep your life humming right along. On the next page, find out how to use an auto-detecting power converter.