Whether you pride your yourself a seasoned traveller or you are booking that very first trip abroad, you know the list of items you need to pack includes a voltage converter. But have you ever wondered why the entire planet isn’t on the same voltage? Or how many voltage systems even exist? To understand this reality, we need to dive into some physics and and a brief history of global electricity.
Before we jump into the physics, let’s have a freshman physics refresher. Alternating Current oscillates at 60 hertz in the US. That means the oscillation frequency is 60 times per second. In Europe that is 50 hertz. Electrical grids around the world have to keep the oscillation frequency stable in the power delivered. Now that you got an A on the quiz, let’s move on!
Now, let’s dispel a myth. America is not the only country on Earth to use 120 volt/60 Hz alternating current. Looking at a map, you’ll quickly learn that all countries and in North and Central America use the US standard as do a smattering of countries in other regions of the world. In contrast, Europe, Australia, as well as the vast majority of Africa and Asia use 220 volt/50 Hz alternating current.
The reason of this is rooted in the Industrial Revolution of the 19th century. Alternating current has its roots in 1881 in England when the town of Godalming started generating electricity through a water wheel-driven system. The resulting power delivered to the town’s residents came in 2 voltages – 250 volts for arc lamps and 40 volts for incandescent lamps. Arc lamps were popular at the time for street lighting. For reference, today’s common florescent lighting is a low pressure arc lamp. This lighting program in England expanded in the subsequent years as town residents grew an appreciation for the new invention.
Meanwhile, across the pond, Thomas Edison was hard at work on his own invention. Not one to shy away from a challenge, Edison built a large power station called the Pearl Street Station in Manhattan. Pear Street was the world’s first permanent commercial central power plant, providing direct current at 110 volts in 1882. Why the lower voltage? Edison and his colleagues in New York felt the 110 voltage to be safer for consumers.
As the 1880’s progressed, alternating current plants came into operation in the eastern United States. These new AC systems utilized higher distribution voltage stepped down via a transformer to the 110 voltage customer utilization already in use in the country. As electricity generating plants continued to sprout up around the US in the 20th century, several different voltage loads were delivered to customers, creating a non-standard power grid across the nation. Meanwhile, large appliances in the US required the higher 220 voltage to power their motors.
In the aftermath of World War II the US Government adopted a standard 117 voltage for power delivery to customers. However, many rural and western areas lagged behind well into the 1960’s. As time went on, Appliance makers adopted a standard 120 or 240 volt requirement and today, all US municipal power customers have access to both 120 volt and 240 volt at 60 Hz.
But why do parts of the world use 220 volts and some 120 volts? Remember those original incandescent lamps used in houses? Incandescent lamps create light by heating a filament until it glows. The filament is enclosed in a glass bulb with a vacuum or inert gas to protect the filament from oxidation. Well, those incandescent lamps can’t withstand the higher 240 voltage.
As time and technology progressed, the old carbon filament was replaced by a metal filament. This new metal filament could be used for more efficient power distribution systems using 220 voltage but since the country’s power grid was already largely established using 120 volts infrastructure, there was no real gain to scrapping the initial system just to go with a new higher-voltage system.
European countries changed over to 240 volt current in the 1950’s to improve transmission efficiency. Enough of the continent’s transmission lines and power generation plants had been damaged during World War II so those countries had the unique opportunity to improve their power delivery system at that time.
So now you understand a little about why there are different voltages in use. But did you know there are a lot more voltages than 120 and 220? And how can different companies deliver products to market if the company has no idea what voltage their oven will be connected to? In any electronic consumer device you are packing, the internal circuitry is a maze of resistors and capacitors. This allows the current flowing through the device to step down (or up) to the necessary stable power your device is designed for. Remember, until the middle of the 20th century, electrical delivery was less than stable. In rural parts of the world, this was (and to some extent still is) a big issue. Your electronic devices are made with this issue in mind. Now, don’t go plugging your US made phone cord directly into a 240 volt circuit – it’s not made for that. But it is made to handle 120 volt or 110 volt current.
How does a voltage converter actually work?
To learn how a voltage converter actually works, we have to dive back into Freshman Physics! Remember all those lectures on Electricity and Magnetism you slept through? Yeah – those Physics Classes. Voltage converters do exactly that – convert voltage. Let’s say you live in the US and you are travelling to France. You want to take your phone and charger, but you need the voltage converter. If you plugged in your standard US 110 volt plug, you’d knock out the power in that wall circuit.
You know you can plug in your phone or your electric razor to charge, but everyone tells you not to plug your laptop or hair dryer into that power converter. But why not? Transformers do not change the frequency of electricity; in many regions with 100–120 V, electricity is supplied at 60 Hz, and 210–240 V regions tend to use 50 Hz. This may affect operation of devices which depend on mains frequency. Equipment with high-powered motors or internal transformers designed to operate at 60 Hz like computers and haridryers may overheat at 50 Hz even if the voltage supplied is correct. If you plan on taking a laptop, be sure you have a suitable transformer for it. You can contact any computer supply company to get a proper transformer.
So, now you know some basics. The voltage and frequency of power supplies are different around the world. Most countries and regions use 220 volts (230 volts to 240 volts)/50 hertz. 20% of countries use 110 volts (120 volts)/60 hertz. 220 volts/60 hertz is the most efficient power supply, but only a few countries using this configuration.
Don’t be afraid of the voltage converter issue. This blog, a bit of time on the internet, and talking to your travel company and your camera batteries, phone, kindle, laptop, and other electronic necessities will be ready for your trip!