International Power Adapters: What You Need to Know

If you’re planning on traveling internationally, finding a power adapter should be as simple as looking up the plug standard for your destination, buying an adapter, and packing your suitcase.

However, if you need more than just a plug adapter, you could accidentally ruin your hair dryer.

First, let’s explore why we have so many different plugs and standards across countries and then let’s look at how to check your label and reduce the risk of accidentally buying the wrong adapter or forgetting a necessary converter.

There are a few key variations in standards between countries (or sometimes even within a country):

  • Ÿ Current
  • Ÿ Voltage
  • Ÿ Frequency
  • Ÿ Outlet and Plug shape


The two main standards for current are AC and DC or Alternating Current and Direct Current. In the US, we developed a standard during the famous war between Tesla and Edison. Edison favored DC, and Tesla AC. The big advantage to AC is that it was capable of traveling greater distances between power stations, and in the end, it was the standard that won out in the USA.

However, not all countries adopted AC. Neither did all yoru devices. Batteries and the internal workings of many electronics also use DC power. In the case of laptops, the large external power brick is actually converting AC power to DC.


Voltage is the force with which electricity travels. It’s often described using a water pressure analogy. Although there are several standards, the most common voltage standards for travelers are 110/120V (USA) and 220/240V (most of Europe).

If your electronics are only meant to handle 110V of force, having 220V shooting through them could be catastrophic.


Frequency for AC power is how often the current alternates each second. In most cases, the standards are 60Hz (America) and 50Hz everywhere that values the metric system. In most cases, this isn’t going to make a difference in performance, but it can occasionally cause problems with devices that use timers.

Outlet and Plug Shapes: A, B, C, or D?

Although there are a lot of different plug shapes, most travel adapters settle for the four most common. The International Trade Administration breaks these down into alphabetical shapes (A, B, C, D and so on) so you can check to see if you need something beyond the usual four for your travels.

Can You Just Use a Power Plug Adapter?

Is that all you would need? You can buy USB adapters and use your USB C cord with a USB A plug. It seems like the same concept should apply.

For many devices, it is that simple. Look at the back of your device where you find the UL listing and other information about your device. In the case of laptops, you’ll locate the information on your power adapter.

The UL listing will tell you the frequency, current, and voltage that your device can handle. If you’re traveling to a country compatible with those standards, you just need to find the right shape of plug.

Devices generally come in three types: those that only comply with one standard, dual mode devices that comply with two standards (switching between 110V and 220V), and those compatible with a wide range of standards. You may need to flip a switch or move a slider in order to convert devices with dual modes.

Do You Need an Adapter or Converter?

Now, should you want to travel with a single voltage device to a country with different voltage, you’ll need a voltage converter. If you travel someplace from a lower voltage (USA) to a higher voltage (Germany), it will be a step-up converter, and if you travel in the opposite direction, it will be a step-down converter. This is the only time you should use a converter, and remember that you don’t need to use them with your laptop. In fact, you might damage your laptop if you do.

In rare cases, you may also need an AC converter to convert DC power to AC or vice versa, but again, your laptop uses DC power already, so do not use a third-party converter with it.

Check with the company that made your laptop to see what you need. If necessary, you may also be able to buy a compatible power adapter in your destination country.


It should be noted that many international hotels have built-in wiring for their guests that don’t require any special adapters or converters to use. Ask before your trip to see what your accommodations offer.

What About Tablets, Phones, and Other USB-Charging Devices?

The good news about USB-charging devices is that you don’t need a plug adapter. In fact, using one would probably ruin your charger. You just need to buy a compatible charger. USB is standardized. Your charger is doing all the work to convert the voltage to the USB charging standard to power your phone.

In fact, USB may be our best hope for standardizing our power charging for the future, between that and wireless charging systems, we may be moving toward the next “electric plug” solution for our international travel.

Although the USB standard has changed over time 1.1 to 2.0 to 3.0 and 3.1, it has done so in a thoughtful way that offers legacy compatibility. You can still plug your USB 2.0 powered device into a USB 3.0 port and charge it. You just don’t see the bandwidth and speed advantages when you do. It’s also easier to replace and upgrade USB ports over time than it is to rewire homes for new electrical standards.

Why do Countries Have Different Shaped Power Outlets?

After a system of power transmission was established (AC vs DC), homes were wired for electricity, but there was no such thing as a power outlet. There wasn’t a good way to patch something into the network temporarily. Devices were wired into the home’s electrical network directly. We still do this with some appliances, like light fixtures and oven hoods, but at the time, it meant there was no such thing as a portable electronic device.

As countries built out electrical systems, there wasn’t need to think about compatibility. It was a wonder that power even standardized between cities and states within a single country. (Actually, that didn’t always happen within countries. Brazil still has incompatible systems within portions of the country according to the International Trade Administration.)

That also meant different countries settled around different voltages and frequencies as power plants were built. Tesla recommended 60 Hz in the US, while Europeans went with the more metrically-compatible 50 Hz. The US went to 120 volts, while Germany settled on 240/400, a standard later adopted by other Europeans.

Now that countries were establishing their standards for transmitting power and houses were getting wired to receive it, an American inventor named Harvey Hubbell II came up with the idea to let people plug their devices into light sockets. You can still buy power adapters you can plug into light sockets today. Hubbell eventually improved the concept to create what we now know of as the American outlet plug with two prongs.

A few years later, someone else upgraded the two prong plug to add a third, grounding prong, which makes the socket a little safer and less likely to shock you when you plug things into it. American outlets also grew two different sized prongs to keep people from accidentally plugging them in the wrong way.

Meanwhile, other countries began developing outlets and plugs without considering compatibility, although it was the outlet that made portable electronics possible. It was just a matter of which standard gained traction in each location. Most country systems also adapted a system that made it only possible to plug your devices in one way, whether it was by making the plugs different shapes, making three of them, or putting them at different angles.

Apple MC556LL/A Laptop AC Adapter Review

The Apple 85W MagSafe Power Adapter is the highest wattage available in this line of Apple MacBook AC adapters. It is designed for use with any 15 or 17 inch MacBook Pro models.

These MagSafe Apple laptop AC adapters bear the companies landmark magnetic design. Rather than plugging into a jack on your MacBook, these adapters instead latch onto your machine via a magnetic connection. Aside from giving your machine a very cool design factor, this is actually a very functional design. First, this design is as efficient as any DC jack connection. However, this magnetic connection is much faster, easier, and more convenient to attach and remove. Also, it doesn’t require any more parts on your machine, which means there’s less to break or require repair.

This is actually a safety feature of the machine as well. A common source of damage to both typical laptop AC adapters and DC jacks is caused when someone trips over or hits the cord connecting the adapter to the machine. In a DC jack connection, this connection is rigid, and the force can bend pins or jacks, or cause stress on the cord and connections themselves, which can damage or outright break your components. With this magnetic connection, the cord simply falls away, with no damage to either component, and even without any kind of accident, a much longer lifespan for your adapter.

Just like Apple’s innovative laptop batteries, these adapters also bear an LED light indicator indicating to you the status of its charging or running state. An amber light indicates your battery is charging, while a green light tells you your battery is fully charged. These adapters are designed with a unique shape as well, meant for the cord to wrap neatly and securely around its own cube designed plug, for convenient storage and portability.

Why Does AC Adapter Polarity Matter?

The AC adapter is an important component of any laptop. Without it, it would not be possible to recharge the laptop’s battery, which is essential for portability. The AC adapter also makes it possible to use the laptop without draining battery life, helping extend battery life on long days. Laptop AC adapters are not all created the same, however, and one of the distinguishing characteristics of different AC adapter designs is their polarity.

The polarity of an AC adapter refers to the way that power flows through the cable and into the laptop itself. The power coming from a wall outlet is what is known as alternating current (or AC power), but the power needed by the laptop is known as direct current (or DC power). The AC adapter converts the AC power into DC power at the correct voltage for the laptop.

The polarity of the adapter happens in the connector that is inserted into the laptop directly. The connector is comprised of a tip and a barrel. The tip is essentially the hole in the middle of the connector and the barrel is the larger area surrounding this hole. Power can only flow in one direction, either from the tip to the barrel or from the barrel to the tip. This is what is meant by polarity.

An adapter with a positive polarity means that its tip is positive and its barrel is negative. An adapter with a negative polarity means that its tip is negative and its barrel is positive. There is no standard design, so adapters and devices are often marked with a symbol to show their polarity. The side connected to the center dot is the tip, and the side connected to the symbol shaped like a C is the barrel.

It is important not to plug an adapter with the wrong polarity into a device. It will not supply power, and in some cases can cause damage to the device or the adapter. Visit Spareparts Warehouse to find a compatible adapter for your laptop, or view specific sections, such as Sony Laptop AC Adapters and Toshiba Laptop AC Adapters to find adapters specific to your laptop’s manufacturer.

Toshiba Laptop Memory Replacement

When looking at upgrade options for a Toshiba laptop, you will find that upgrading the laptop memory is likely to have the greatest impact on the overall performance. Programs store their data in RAM when they are running. If multiple programs are open at once and the laptop runs out of free memory, it must begin using the hard drive to store and retrieve the extra data. Since hard drives are much slower than RAM, this results in slower performance. Upgrading memory allows users to run more programs with fewer slowdowns and speed up operating system load time.

Replacing your Toshiba laptop memory is one of the simplest upgrades to make. The basic steps are as follows:

  1. Disconnect the AC adapter and remove the battery to ensure no power is going to the laptop. This reduces any risk of electric shock when disassembling the machine. The battery is most often removed by sliding the battery slider and removing the battery.
  2. Locate the memory access panel on the bottom of the machine. It is usually marked with an icon that resembles a memory stick. In some cases it may be located behind the battery. If you have trouble locating this panel, consult your manual or a service manual for the exact location.
  3. Remove any screws securing the memory access panel in place and remove it.
  4. Gently release the two fingers holding the memory stick on each side and it should swing upwards. Carefully pull it out of the slot. Repeat for the second stick if there is one.
  5. Place the new memory stick in the lower slot and snap it down into place. Repeat for the upper memory stick if there is one.
  6. Replace the memory access panel and screws.
  7. Replace the battery and reconnect the AC adapter. Boot up the computer and test that the full amount of memory is recognized by the computer.

At this point, if the memory is recognized and the laptop is working properly, you are finished. If you are having trouble you may want to check that you selected the proper memory module for your machine, or the possibility that the memory is not seated completely in the slot.

Laptop Parts and Symptoms

One of the most common issues with laptop batteries is overheating. Not that the batteries are designed poorly or improperly but due to, in most cases, user wear and tear. While the laptop is using the AC adapter for power the battery acts as a backup in case of a loss of power or accidental unplugging. During this AC power use the battery becomes hotter than it would if being used independently. To lessen the chances of this overheating, which leads to a shorter life expectancy of the battery, keep the AC power adapter plugged in only if you need to charge the battery while using the device.

If the battery is consistently hot to the touch, remove it and allow it to cool down making sure it is close to room temperature before reinserting it. Should the battery continue to overheat or get too hot it will probably need to be replaced. Always replace a defective battery as soon as possible as it could cause irreparable damage to the laptop in question. In addition to overheating, failure to charge or hold a charge is another very common issue with laptop batteries.

First check to see if the AC adapter is securely plugged into the device; the tightness of the connection will vary from laptop to laptop but it should be held in place well. To check for a good connection look for the battery charging LED if one is present on your laptop.

If it is not on wiggle the cord to see if the connection makes and breaks contact. If you notice a flickering LED light then the solution is a new adapter which is far better than needed to purchase a new battery or a new DC power jack which can be repaired by a common user with a little instruction and help.

Issues with third-party batteries and Sony laptops

Sony laptops are arguably some of the best Windows laptops available, but there are a few issues that many users won’t appreciate. One of these issues is a type of protection that Sony includes to prevent users from using third-party batteries with their Sony laptop.

Sony would prefer that users use only Sony laptop batteries, partly because it means they must be purchased directly from the manufacturer, but also to ensure quality. Users who have found a trusted third-party manufacturer for their laptop batteries, however, are likely to be frustrated by this limitation. Fortunately, there is a workaround to let you use third-party batteries with your Sony laptop, as the battery check is a software program rather than something included in the Sony system board. Follow these steps to disable the software check.

  1. Power down the laptop, remove the battery, connect the AC adapter, and power the laptop back up.
  2. Click the Start button and type “msconfig.exe”. You may need to enter your password to continue.
  3. Click the “Startup” tab and look for a listing for “ISBMgr.exe”. Uncheck the box.
  4. Click “OK” to save the changes, and choose to restart the laptop. There may be a popup once you restart; alerting you that certain programs have been disabled. Simply dismiss this dialog box.

Now you can install your third-party battery, and you should find that it works without problems. Visit our Sony laptop parts page to view other parts and upgrades that are compatible with your laptop.

Diagnosing a Laptop AC Adapter Problem

Laptop AC adapters can sometimes take a lot of abuse. As an external part of a laptop, they are designed to be rugged, but problems can still crop up from time to time. If you suspect that yours may be having an issue, here are some steps for diagnosing a laptop AC adapter problem.

  1. Try another power outlet. This may sound silly, but if you are not getting power to your laptop through the AC adapter, try another power socket to ensure that is not the cause of the problem.
  2. If possible, try another AC adapter. This may be more difficult, but if you have a friend or a repair shop that has a compatible AC adapter, try one that is known to be working. If the problems still persist, you know the AC adapter is not to blame.
  3. Try running the laptop without the battery. Sometimes problems with the battery can cause symptoms unrelated to the AC adapter. If the laptop runs fine when running only from the AC adapter, it is likely caused by a faulty battery or some other component.
  4. Look for signs of wear and tear on the AC adapter. Large cracks on the “brick” or transformer could be signs of problems, as can frayed wires or bulging. If any of these conditions look serious, replace your AC adapter.
  5. Listen for strange noises. AC adapters that are failing often make whining noises or other strange sounds. Replace the AC adapter if necessary.

If you have tried the steps above and are still uncertain whether your laptop AC adapter is faulty, it may still be a good idea to order a replacement. As one of the least expensive parts of a laptop to replace, it may be worth the peace of mind knowing that your AC adapter is working correctly.

How AC Adapters Work

Laptops are useless without AC adapters. They are what run your laptop when your battery dies. They are what charge that battery when you want to use it on the go. With that in mind, it’s important to have a basic understanding of how they do what they do, especially if it comes time to replace them.

A laptop AC adapter will consist of essentially three main parts: the cord that carries unusable AC to the box, the box that converts the AC to DC, and the cord that carries the usable DC to the laptop. Your house is powered with AC, or alternating current, because it travels well without losing energy, but alternating current is not usable by laptops. They require direct current, or DC, power.

The box of your adapter technically does more than simply converting current, or rather there is more to the process. As alternating current enters the box from the cord connected to your wall, it is run through a transformer. This drops the current from about 110 volts to around 19 volts, which is what most Sony laptops can work with. Other brands of laptop often use 15 Volts, but most other variations are plus or minus a volt in either direction. The current then runs through a rectifier which essentially forces the current out in one direction only, thus making direct current. Finally, the current runs through a regulator, ensuring a steady stream of voltage despite any changes in power consumption. After running through all these components, the current continues through the second cord, and into your laptop.

Knowing the basics of AC adapters will allow you to make some more educated decisions on replacement or upgrade adapters. First, check your cords. Match your main power, or AC, cord to whatever plug you’ll be using. For example, plugs in Europe are different than in the US, and plugs in your car or on a plane are different than the ones in your home. Also, invest in a surge protector to help ensure the longevity of your AC adapter, essentially protecting it from being overloaded.

Your laptop will also require specific voltage from your adapter, and a minimum wattage as well, typically listed on the underside of your machine, or available from the manufacturer. When it comes to wattage, you can get higher than what is listed on your machine’s specifications, but going lower can cause the box to overheat, and shortening the life of the laptop AC adapter.

As for the DC cord, the main thing to look for is the connector. If it doesn’t fit the DC jack on your machine, it won’t do you any good at all. If you’re not sure, check with your spare parts retailer, chances are they will be able to assist you in finding an adapter that will fit your machine. Also, when looking at replacing an adapter, be sure to confirm that the problem isn’t with the physical DC jack on your machine, as it can become loose or unsoldered. A loose DC jack can cause problems that may simulate issues with your AC adapter and may require the DC jack to be repaired.

Review of types on connectors found on AC adapters

When it comes to laptop AC adapters, there are a wide variety of connectors that connect the adapter to the laptop’s power supply. Manufacturers specifically try to make their adapter unique for each model, and even compared to other manufacturers, to avoid a user plugging an adapter into the wrong machine, which could cause damage. Here we will look at a few of the most common types of connectors.

Barrel Connectors

Most modern laptop AC adapters use a “barrel” type of connector. It consists of a cylindrical shaft that is hollow inside. When the barrel is connected, a pin (tip) goes inside the barrel, and the outer portion of the barrel makes contact with a different part of the power supply. The tip usually carries the positive pole while the barrel carries the negative pole. Barrel connectors come in a wide variety of sizes to avoid confusion between different manufacturers and models. For example, HP laptop parts often use a different pin and barrel size than another manufacturer such as Acer.

3-Pin and 4-Pin Connectors

Some laptops and AC adapters use a 3-pin or 4-pin type of connector, also referred to as a “Snap and Lock” type. These connectors use a large cylindrical connector with 3 or 4 pins inside. Snap and lock connectors are particularly useful in laptops that are designed for durability, as they are very stable and secure, and not prone to breakage.

Oval Connectors

Oval connectors are similar to barrel connectors, but utilize and oval shape to prevent connecting them to standard barrel connections, since connecting an adapter to the wrong laptop could cause damage to the system board or other components, requiring a costly laptop repair. They are not used frequently.

Octagon Connectors

Octagon connectors are similar to snap and lock connectors, but they utilize 8 pins that give even more stability and a more solid connection.

How to Choose a Replacement Adapter for Your Laptop

Your laptop makes your office, your entertainment and your important files portable and convenient. You can take your laptop anywhere you go, whether you’re working at home, the coffee shop or the park. One of the most important laptop accessories you can have is your laptop adapter or power cord. Your laptop needs power to keep you on the go, and a lost or broken laptop adapter can seriously slow you down. Even if you haven’t lost your laptop adapter, you may want to purchase a back-up power cord to keep at home or at the office. Here are some steps to help you quickly find a replacement laptop adapter or power cord, so you can get back to work and play.

Choosing a Replacement Adapter:

Find your laptop’s model number.

You may find this number located on a sticker on the bottom or side of your laptop computer. If you can’t find it there, check your user manual or search your laptop’s built-in help program for the model number. You can also find it under your laptop’s system properties.

Find your wattage requirements.

In addition to your laptop model number, you will need to find out the voltage requirements for the laptop adapter. Laptop adapters have varying voltage (V) outputs, and using the wrong laptop adapter can damage your computer. Check your user’s manual for voltage requirements information for your laptop. The output voltage will usually be listed as DC voltage. You may also want to check for product or part numbers that are compatible with your laptop model.

Find a compatible laptop adapter.

Look for the compatibility lists in descriptions of laptop adapters you are looking at. Sometimes the compatible laptop models are listed in the product description or in a separate list. Laptop model numbers can often look similar, so make sure the model numbers match exactly. Laptop adapter and power cord product descriptions typically list the manufacturer, part number and a partial description as well. If you find an adapter with the correct output voltage, but the wrong port connector, you may be able to find port attachments that will adapt the connector to the power port on your laptop.