Wanderlust World Wanderlust World American homes have 220 volts at 60 Hertz coming into the house, entering via three wires, two sides of 110 each and a neutral. The 220 appliances in your home operate on both sides of the 110, making 220. Almost everything else works on either side of the 110 and neutral. Most other countries do not divide the phases, and also operate at 50 Hertz rather than 60.You will need to take the frequency into consideration for your conversion.
Transformers are made of two coils of wire placed near each other, the ratio of which determines the rate of conversion. And the directions are reversible. A ratio of 2 to 1 doubles in one direction and halves in the other. But you must also consider wattage. A small 50 watt transformer works for appliances like shavers and clocks, but you need higher wattage for hair dryers, curling irons or larger appliances. Price of transformers increases with wattage, and ranges from under $10 up to several hundred. But transformers cannot change the frequency--60 Hertz in will always give you 60 Hertz out.
For small appliances up to 50 or 60 watts, you can buy a converter and plug it directly into a 110 volt wall socket and then plug your small 220 volt appliance into the converter. Be careful that you do not exceed the wattage rating of the transformer. Look on your appliance for a wattage rating. Also, since you cannot change the frequency, items like clocks designed to run of 50 Hertz may run faster on 60 Hertz. This may not be true with digital clocks. Go to dvdoverseas.com/store/index.html?loadfile=catalog10_0.html to see an example of a small converter.
Larger appliances require larger transformers. Go to the above link to see some examples. But be careful. Major appliances designed to work on 220 volts and 50 Hertz may work using transformers. But they may not work well. Dryer motors and refrigerator compressors may run at different speeds and overheat or wear out faster. And the number of wire connections may be different. So in making your decisions to move, consider the cost of shipping, the cost of the transformer and the risk of a shortened lifespan or failure of your appliance.
More sophisticated items may not need conversion. Modern technology takes into consideration the shrinking globe we live on, and is designing many items to operate on all systems. Examples would include most cell phone and camera chargers and laptops, and may also include TV sets and desktops. Look on your equipment label or literature to find out. A cell phone charger purchased in South America may say, "Entrada: 100-240V~ 50/60Hz 0.1A." This will work almost anywhere in the world without conversion.